diff --git a/packages/babel-generator/test/fixtures/flow/declare-statements/input.js b/packages/babel-generator/test/fixtures/flow/declare-statements/input.js
index a0874c4d44a4..3a2d2aa6a74e 100644
--- a/packages/babel-generator/test/fixtures/flow/declare-statements/input.js
+++ b/packages/babel-generator/test/fixtures/flow/declare-statements/input.js
@@ -11,13 +11,13 @@ declare class A { static [ indexer: number]: string }
 declare class A { static () : number }
 declare class B { (): number }
 declare class A mixins B<T>, C {}
-declare type A = string
+declare type A1 = string
 declare type T<U> = { [k:string]: U }
-declare type B = {
+declare type B1 = {
   fn?: (foo: string) => void,
 }
-declare interface I { foo: string }
-declare interface I<T> { foo: T }
+declare interface I1 { foo: string }
+declare interface I2<T> { foo: T }
 declare module.exports: { foo: string }
 declare opaque type Foo<T>: Bar<T>;
 declare opaque type ID;
diff --git a/packages/babel-generator/test/fixtures/flow/declare-statements/output.js b/packages/babel-generator/test/fixtures/flow/declare-statements/output.js
index 7be6ae40cec7..c5f087d49ab0 100644
--- a/packages/babel-generator/test/fixtures/flow/declare-statements/output.js
+++ b/packages/babel-generator/test/fixtures/flow/declare-statements/output.js
@@ -22,17 +22,17 @@ declare class B {
   (): number
 }
 declare class A mixins B<T>, C {}
-declare type A = string;
+declare type A1 = string;
 declare type T<U> = {
   [k: string]: U
 };
-declare type B = {
+declare type B1 = {
   fn?: (foo: string) => void
 };
-declare interface I {
+declare interface I1 {
   foo: string
 }
-declare interface I<T> {
+declare interface I2<T> {
   foo: T
 }
 declare module.exports: {
diff --git a/packages/babel-generator/test/fixtures/flow/def-site-variance/input.js b/packages/babel-generator/test/fixtures/flow/def-site-variance/input.js
index 9f00e80993d1..0891ba212de5 100644
--- a/packages/babel-generator/test/fixtures/flow/def-site-variance/input.js
+++ b/packages/babel-generator/test/fixtures/flow/def-site-variance/input.js
@@ -5,10 +5,10 @@ type T2 = { +p: T };
 type T3 = { -p: T };
 type T4 = { +[k:K]: V };
 type T5 = { -[k:K]: V };
-interface I { +p: T }
-interface I { -p: T }
-interface I { +[k:K]: V }
-interface I { -[k:K]: V }
+interface I1 { +p: T }
+interface I2 { -p: T }
+interface I3 { +[k:K]: V }
+interface I4 { -[k:K]: V }
 declare class I { +p: T }
 declare class I { -p: T }
 declare class I { +[k:K]: V }
diff --git a/packages/babel-generator/test/fixtures/flow/def-site-variance/output.js b/packages/babel-generator/test/fixtures/flow/def-site-variance/output.js
index 5c2b69d1a6dd..66dd195d22e1 100644
--- a/packages/babel-generator/test/fixtures/flow/def-site-variance/output.js
+++ b/packages/babel-generator/test/fixtures/flow/def-site-variance/output.js
@@ -15,16 +15,16 @@ type T4 = {
 type T5 = {
   -[k: K]: V
 };
-interface I {
+interface I1 {
   +p: T
 }
-interface I {
+interface I2 {
   -p: T
 }
-interface I {
+interface I3 {
   +[k: K]: V
 }
-interface I {
+interface I4 {
   -[k: K]: V
 }
 declare class I {
diff --git a/packages/babel-generator/test/fixtures/flow/internal-slot/input.js b/packages/babel-generator/test/fixtures/flow/internal-slot/input.js
index b00d3bd76f22..6056da54458a 100644
--- a/packages/babel-generator/test/fixtures/flow/internal-slot/input.js
+++ b/packages/babel-generator/test/fixtures/flow/internal-slot/input.js
@@ -1,7 +1,7 @@
 declare class C { static [[foo]]: T }
 declare class C { [[foo]]: T }
-interface I { [[foo]]: X }
-interface I { [[foo]](): X }
+interface I1 { [[foo]]: X }
+interface I2 { [[foo]](): X }
 type T1 = { [[foo]]: X }
 type T2 = { [[foo]](): X }
 type T3 = { [[foo]]?: X }
diff --git a/packages/babel-generator/test/fixtures/flow/internal-slot/output.js b/packages/babel-generator/test/fixtures/flow/internal-slot/output.js
index 2a48fb9f186a..3b2b5ece1a23 100644
--- a/packages/babel-generator/test/fixtures/flow/internal-slot/output.js
+++ b/packages/babel-generator/test/fixtures/flow/internal-slot/output.js
@@ -4,10 +4,10 @@ declare class C {
 declare class C {
   [[foo]]: T
 }
-interface I {
+interface I1 {
   [[foo]]: X
 }
-interface I {
+interface I2 {
   [[foo]]() => X
 }
 type T1 = {
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js
index dab9a962acf7..7e5fb6309d97 100644
--- a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js
@@ -1,7 +1,7 @@
-interface A {
+interface A1 {
   @@iterator(): Iterator<File>;
 }
 
-interface A {
+interface A2 {
   @@asyncIterator(): Iterator<File>;
 }
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js
index ef726ab2fc5b..57b22ad84495 100644
--- a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js
@@ -1,6 +1,6 @@
-interface A {
+interface A1 {
   @@iterator(): Iterator<File>
 }
-interface A {
+interface A2 {
   @@asyncIterator(): Iterator<File>
 }
\ No newline at end of file
diff --git a/packages/babel-parser/src/parser/expression.js b/packages/babel-parser/src/parser/expression.js
index 9b48c7129e2f..5aba0020634a 100644
--- a/packages/babel-parser/src/parser/expression.js
+++ b/packages/babel-parser/src/parser/expression.js
@@ -1944,7 +1944,7 @@ export default class ExpressionParser extends LValParser {
         node.params[i],
         BIND_VAR,
         allowDuplicates ? null : nameHash,
-        "function paramter list",
+        "function parameter list",
       );
     }
   }
diff --git a/packages/babel-parser/src/plugins/flow.js b/packages/babel-parser/src/plugins/flow.js
index 024a21baa5ab..e1a9e72a291c 100644
--- a/packages/babel-parser/src/plugins/flow.js
+++ b/packages/babel-parser/src/plugins/flow.js
@@ -14,6 +14,8 @@ import {
   type BindingTypes,
   BIND_NONE,
   BIND_LEXICAL,
+  BIND_VAR,
+  BIND_FUNCTION,
   SCOPE_ARROW,
   SCOPE_OTHER,
 } from "../util/scopeflags";
@@ -270,6 +272,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       node.id = this.flowParseTypeAnnotatableIdentifier(
         /*allowPrimitiveOverride*/ true,
       );
+      this.scope.declareName(node.id.name, BIND_VAR, node.id.start);
       this.semicolon();
       return this.finishNode(node, "DeclareVariable");
     }
@@ -462,6 +465,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     ): void {
       node.id = this.flowParseRestrictedIdentifier(/*liberal*/ !isClass);
 
+      this.scope.declareName(
+        node.id.name,
+        isClass ? BIND_FUNCTION : BIND_LEXICAL,
+        node.id.start,
+      );
+
       if (this.isRelational("<")) {
         node.typeParameters = this.flowParseTypeParameterDeclaration();
       } else {
diff --git a/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/input.js b/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/input.js
new file mode 100644
index 000000000000..6e0495a39c96
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/input.js
@@ -0,0 +1,3 @@
+interface Foo {}
+
+export type { Foo }
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/output.json b/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/output.json
new file mode 100644
index 000000000000..15c57d370772
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/interfaces-module-and-script/implements-exports/output.json
@@ -0,0 +1,160 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 37,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 19
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 37,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 19
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "InterfaceDeclaration",
+        "start": 0,
+        "end": 16,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 16
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 10,
+          "end": 13,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 10
+            },
+            "end": {
+              "line": 1,
+              "column": 13
+            },
+            "identifierName": "Foo"
+          },
+          "name": "Foo"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 14,
+          "end": 16,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 16
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "ExportNamedDeclaration",
+        "start": 18,
+        "end": 37,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 19
+          }
+        },
+        "specifiers": [
+          {
+            "type": "ExportSpecifier",
+            "start": 32,
+            "end": 35,
+            "loc": {
+              "start": {
+                "line": 3,
+                "column": 14
+              },
+              "end": {
+                "line": 3,
+                "column": 17
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 32,
+              "end": 35,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 14
+                },
+                "end": {
+                  "line": 3,
+                  "column": 17
+                },
+                "identifierName": "Foo"
+              },
+              "name": "Foo"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 32,
+              "end": 35,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 14
+                },
+                "end": {
+                  "line": 3,
+                  "column": 17
+                },
+                "identifierName": "Foo"
+              },
+              "name": "Foo"
+            }
+          }
+        ],
+        "source": null,
+        "exportKind": "type",
+        "declaration": null
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/input.js
new file mode 100644
index 000000000000..fa5ff14cb9be
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/input.js
@@ -0,0 +1,2 @@
+declare class C1 {}
+class C1 {}
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/options.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/options.json
new file mode 100644
index 000000000000..06ad6ded6032
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/class/options.json
@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'C1' has already been declared (2:6)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/input.js
new file mode 100644
index 000000000000..d9470b0fd596
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/input.js
@@ -0,0 +1,6 @@
+declare class C1{}
+declare class C1{}
+
+declare module M1 {
+  declare class C1 {}
+}
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/output.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/output.json
new file mode 100644
index 000000000000..149ca744eb22
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-class/output.json
@@ -0,0 +1,253 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 82,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 6,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 82,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 6,
+        "column": 1
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 18,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 18
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 16,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 16
+            },
+            "identifierName": "C1"
+          },
+          "name": "C1"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 16,
+          "end": 18,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 1,
+              "column": 18
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "DeclareClass",
+        "start": 19,
+        "end": 37,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 18
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 33,
+          "end": 35,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 14
+            },
+            "end": {
+              "line": 2,
+              "column": 16
+            },
+            "identifierName": "C1"
+          },
+          "name": "C1"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 35,
+          "end": 37,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 16
+            },
+            "end": {
+              "line": 2,
+              "column": 18
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "DeclareModule",
+        "start": 39,
+        "end": 82,
+        "loc": {
+          "start": {
+            "line": 4,
+            "column": 0
+          },
+          "end": {
+            "line": 6,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 54,
+          "end": 56,
+          "loc": {
+            "start": {
+              "line": 4,
+              "column": 15
+            },
+            "end": {
+              "line": 4,
+              "column": 17
+            },
+            "identifierName": "M1"
+          },
+          "name": "M1"
+        },
+        "body": {
+          "type": "BlockStatement",
+          "start": 57,
+          "end": 82,
+          "loc": {
+            "start": {
+              "line": 4,
+              "column": 18
+            },
+            "end": {
+              "line": 6,
+              "column": 1
+            }
+          },
+          "body": [
+            {
+              "type": "DeclareClass",
+              "start": 61,
+              "end": 80,
+              "loc": {
+                "start": {
+                  "line": 5,
+                  "column": 2
+                },
+                "end": {
+                  "line": 5,
+                  "column": 21
+                }
+              },
+              "id": {
+                "type": "Identifier",
+                "start": 75,
+                "end": 77,
+                "loc": {
+                  "start": {
+                    "line": 5,
+                    "column": 16
+                  },
+                  "end": {
+                    "line": 5,
+                    "column": 18
+                  },
+                  "identifierName": "C1"
+                },
+                "name": "C1"
+              },
+              "typeParameters": null,
+              "extends": [],
+              "implements": [],
+              "mixins": [],
+              "body": {
+                "type": "ObjectTypeAnnotation",
+                "start": 78,
+                "end": 80,
+                "loc": {
+                  "start": {
+                    "line": 5,
+                    "column": 19
+                  },
+                  "end": {
+                    "line": 5,
+                    "column": 21
+                  }
+                },
+                "callProperties": [],
+                "properties": [],
+                "indexers": [],
+                "internalSlots": [],
+                "exact": false
+              }
+            }
+          ]
+        },
+        "kind": "CommonJS"
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/input.js
new file mode 100644
index 000000000000..fb98eb970189
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/input.js
@@ -0,0 +1,3 @@
+declare function F1(): void
+declare function F1(): void
+function F1() {}
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/output.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/output.json
new file mode 100644
index 000000000000..ad507ae14079
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-function/output.json
@@ -0,0 +1,249 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 72,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 16
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 72,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 16
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareFunction",
+        "start": 0,
+        "end": 27,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 27
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 17,
+          "end": 27,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 17
+            },
+            "end": {
+              "line": 1,
+              "column": 27
+            },
+            "identifierName": "F1"
+          },
+          "name": "F1",
+          "typeAnnotation": {
+            "type": "TypeAnnotation",
+            "start": 19,
+            "end": 27,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 19
+              },
+              "end": {
+                "line": 1,
+                "column": 27
+              }
+            },
+            "typeAnnotation": {
+              "type": "FunctionTypeAnnotation",
+              "start": 19,
+              "end": 27,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 19
+                },
+                "end": {
+                  "line": 1,
+                  "column": 27
+                }
+              },
+              "typeParameters": null,
+              "params": [],
+              "rest": null,
+              "returnType": {
+                "type": "VoidTypeAnnotation",
+                "start": 23,
+                "end": 27,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 23
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 27
+                  }
+                }
+              }
+            }
+          }
+        },
+        "predicate": null
+      },
+      {
+        "type": "DeclareFunction",
+        "start": 28,
+        "end": 55,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 27
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 45,
+          "end": 55,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 17
+            },
+            "end": {
+              "line": 2,
+              "column": 27
+            },
+            "identifierName": "F1"
+          },
+          "name": "F1",
+          "typeAnnotation": {
+            "type": "TypeAnnotation",
+            "start": 47,
+            "end": 55,
+            "loc": {
+              "start": {
+                "line": 2,
+                "column": 19
+              },
+              "end": {
+                "line": 2,
+                "column": 27
+              }
+            },
+            "typeAnnotation": {
+              "type": "FunctionTypeAnnotation",
+              "start": 47,
+              "end": 55,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 19
+                },
+                "end": {
+                  "line": 2,
+                  "column": 27
+                }
+              },
+              "typeParameters": null,
+              "params": [],
+              "rest": null,
+              "returnType": {
+                "type": "VoidTypeAnnotation",
+                "start": 51,
+                "end": 55,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 23
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 27
+                  }
+                }
+              }
+            }
+          }
+        },
+        "predicate": null
+      },
+      {
+        "type": "FunctionDeclaration",
+        "start": 56,
+        "end": 72,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 16
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 65,
+          "end": 67,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 9
+            },
+            "end": {
+              "line": 3,
+              "column": 11
+            },
+            "identifierName": "F1"
+          },
+          "name": "F1"
+        },
+        "generator": false,
+        "async": false,
+        "params": [],
+        "body": {
+          "type": "BlockStatement",
+          "start": 70,
+          "end": 72,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 14
+            },
+            "end": {
+              "line": 3,
+              "column": 16
+            }
+          },
+          "body": [],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/input.js
new file mode 100644
index 000000000000..21b4f11b204c
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/input.js
@@ -0,0 +1,3 @@
+declare var V1;
+declare var V1;
+var V1;
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/output.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/output.json
new file mode 100644
index 000000000000..b96badb7fe54
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/declare-var/output.json
@@ -0,0 +1,150 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 39,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 7
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 39,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 7
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareVariable",
+        "start": 0,
+        "end": 15,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 15
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 12,
+          "end": 14,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 12
+            },
+            "end": {
+              "line": 1,
+              "column": 14
+            },
+            "identifierName": "V1"
+          },
+          "name": "V1"
+        }
+      },
+      {
+        "type": "DeclareVariable",
+        "start": 16,
+        "end": 31,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 15
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 28,
+          "end": 30,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 12
+            },
+            "end": {
+              "line": 2,
+              "column": 14
+            },
+            "identifierName": "V1"
+          },
+          "name": "V1"
+        }
+      },
+      {
+        "type": "VariableDeclaration",
+        "start": 32,
+        "end": 39,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 7
+          }
+        },
+        "declarations": [
+          {
+            "type": "VariableDeclarator",
+            "start": 36,
+            "end": 38,
+            "loc": {
+              "start": {
+                "line": 3,
+                "column": 4
+              },
+              "end": {
+                "line": 3,
+                "column": 6
+              }
+            },
+            "id": {
+              "type": "Identifier",
+              "start": 36,
+              "end": 38,
+              "loc": {
+                "start": {
+                  "line": 3,
+                  "column": 4
+                },
+                "end": {
+                  "line": 3,
+                  "column": 6
+                },
+                "identifierName": "V1"
+              },
+              "name": "V1"
+            },
+            "init": null
+          }
+        ],
+        "kind": "var"
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/input.js
new file mode 100644
index 000000000000..bca93948ce50
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/input.js
@@ -0,0 +1,2 @@
+interface I {};
+interface I {};
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/options.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/options.json
new file mode 100644
index 000000000000..5672ce1b6444
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/interface/options.json
@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'I' has already been declared (2:10)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/input.js b/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/input.js
new file mode 100644
index 000000000000..273aa1c7176c
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/input.js
@@ -0,0 +1,2 @@
+type T1 = string;
+type T1 = number;
diff --git a/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/options.json b/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/options.json
new file mode 100644
index 000000000000..946261f4e872
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/multiple-declarations/type/options.json
@@ -0,0 +1,8 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ],
+  "throws": "Identifier 'T1' has already been declared (2:5)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/regression/issue-10044/input.js b/packages/babel-parser/test/fixtures/flow/regression/issue-10044/input.js
new file mode 100644
index 000000000000..4d3e8c48a837
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/regression/issue-10044/input.js
@@ -0,0 +1,8 @@
+declare class C1 {}
+declare interface I1 {}
+declare type T1 = number;
+
+interface I2 {}
+type T2 = number;
+
+export type { C1, I1, I2, T1, T2 }
diff --git a/packages/babel-parser/test/fixtures/flow/regression/issue-10044/output.json b/packages/babel-parser/test/fixtures/flow/regression/issue-10044/output.json
new file mode 100644
index 000000000000..5df63e757a77
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/regression/issue-10044/output.json
@@ -0,0 +1,564 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 140,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 8,
+      "column": 34
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 140,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 8,
+        "column": 34
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 19,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 19
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 16,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 16
+            },
+            "identifierName": "C1"
+          },
+          "name": "C1"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 17,
+          "end": 19,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 17
+            },
+            "end": {
+              "line": 1,
+              "column": 19
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "DeclareInterface",
+        "start": 20,
+        "end": 43,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 23
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 38,
+          "end": 40,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 18
+            },
+            "end": {
+              "line": 2,
+              "column": 20
+            },
+            "identifierName": "I1"
+          },
+          "name": "I1"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 41,
+          "end": 43,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 21
+            },
+            "end": {
+              "line": 2,
+              "column": 23
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "DeclareTypeAlias",
+        "start": 44,
+        "end": 69,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 25
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 57,
+          "end": 59,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 13
+            },
+            "end": {
+              "line": 3,
+              "column": 15
+            },
+            "identifierName": "T1"
+          },
+          "name": "T1"
+        },
+        "typeParameters": null,
+        "right": {
+          "type": "NumberTypeAnnotation",
+          "start": 62,
+          "end": 68,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 18
+            },
+            "end": {
+              "line": 3,
+              "column": 24
+            }
+          }
+        }
+      },
+      {
+        "type": "InterfaceDeclaration",
+        "start": 71,
+        "end": 86,
+        "loc": {
+          "start": {
+            "line": 5,
+            "column": 0
+          },
+          "end": {
+            "line": 5,
+            "column": 15
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 81,
+          "end": 83,
+          "loc": {
+            "start": {
+              "line": 5,
+              "column": 10
+            },
+            "end": {
+              "line": 5,
+              "column": 12
+            },
+            "identifierName": "I2"
+          },
+          "name": "I2"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 84,
+          "end": 86,
+          "loc": {
+            "start": {
+              "line": 5,
+              "column": 13
+            },
+            "end": {
+              "line": 5,
+              "column": 15
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "TypeAlias",
+        "start": 87,
+        "end": 104,
+        "loc": {
+          "start": {
+            "line": 6,
+            "column": 0
+          },
+          "end": {
+            "line": 6,
+            "column": 17
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 92,
+          "end": 94,
+          "loc": {
+            "start": {
+              "line": 6,
+              "column": 5
+            },
+            "end": {
+              "line": 6,
+              "column": 7
+            },
+            "identifierName": "T2"
+          },
+          "name": "T2"
+        },
+        "typeParameters": null,
+        "right": {
+          "type": "NumberTypeAnnotation",
+          "start": 97,
+          "end": 103,
+          "loc": {
+            "start": {
+              "line": 6,
+              "column": 10
+            },
+            "end": {
+              "line": 6,
+              "column": 16
+            }
+          }
+        }
+      },
+      {
+        "type": "ExportNamedDeclaration",
+        "start": 106,
+        "end": 140,
+        "loc": {
+          "start": {
+            "line": 8,
+            "column": 0
+          },
+          "end": {
+            "line": 8,
+            "column": 34
+          }
+        },
+        "specifiers": [
+          {
+            "type": "ExportSpecifier",
+            "start": 120,
+            "end": 122,
+            "loc": {
+              "start": {
+                "line": 8,
+                "column": 14
+              },
+              "end": {
+                "line": 8,
+                "column": 16
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 120,
+              "end": 122,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 14
+                },
+                "end": {
+                  "line": 8,
+                  "column": 16
+                },
+                "identifierName": "C1"
+              },
+              "name": "C1"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 120,
+              "end": 122,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 14
+                },
+                "end": {
+                  "line": 8,
+                  "column": 16
+                },
+                "identifierName": "C1"
+              },
+              "name": "C1"
+            }
+          },
+          {
+            "type": "ExportSpecifier",
+            "start": 124,
+            "end": 126,
+            "loc": {
+              "start": {
+                "line": 8,
+                "column": 18
+              },
+              "end": {
+                "line": 8,
+                "column": 20
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 124,
+              "end": 126,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 18
+                },
+                "end": {
+                  "line": 8,
+                  "column": 20
+                },
+                "identifierName": "I1"
+              },
+              "name": "I1"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 124,
+              "end": 126,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 18
+                },
+                "end": {
+                  "line": 8,
+                  "column": 20
+                },
+                "identifierName": "I1"
+              },
+              "name": "I1"
+            }
+          },
+          {
+            "type": "ExportSpecifier",
+            "start": 128,
+            "end": 130,
+            "loc": {
+              "start": {
+                "line": 8,
+                "column": 22
+              },
+              "end": {
+                "line": 8,
+                "column": 24
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 128,
+              "end": 130,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 22
+                },
+                "end": {
+                  "line": 8,
+                  "column": 24
+                },
+                "identifierName": "I2"
+              },
+              "name": "I2"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 128,
+              "end": 130,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 22
+                },
+                "end": {
+                  "line": 8,
+                  "column": 24
+                },
+                "identifierName": "I2"
+              },
+              "name": "I2"
+            }
+          },
+          {
+            "type": "ExportSpecifier",
+            "start": 132,
+            "end": 134,
+            "loc": {
+              "start": {
+                "line": 8,
+                "column": 26
+              },
+              "end": {
+                "line": 8,
+                "column": 28
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 132,
+              "end": 134,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 26
+                },
+                "end": {
+                  "line": 8,
+                  "column": 28
+                },
+                "identifierName": "T1"
+              },
+              "name": "T1"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 132,
+              "end": 134,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 26
+                },
+                "end": {
+                  "line": 8,
+                  "column": 28
+                },
+                "identifierName": "T1"
+              },
+              "name": "T1"
+            }
+          },
+          {
+            "type": "ExportSpecifier",
+            "start": 136,
+            "end": 138,
+            "loc": {
+              "start": {
+                "line": 8,
+                "column": 30
+              },
+              "end": {
+                "line": 8,
+                "column": 32
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 136,
+              "end": 138,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 30
+                },
+                "end": {
+                  "line": 8,
+                  "column": 32
+                },
+                "identifierName": "T2"
+              },
+              "name": "T2"
+            },
+            "exported": {
+              "type": "Identifier",
+              "start": 136,
+              "end": 138,
+              "loc": {
+                "start": {
+                  "line": 8,
+                  "column": 30
+                },
+                "end": {
+                  "line": 8,
+                  "column": 32
+                },
+                "identifierName": "T2"
+              },
+              "name": "T2"
+            }
+          }
+        ],
+        "source": null,
+        "exportKind": "type",
+        "declaration": null
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/options.json b/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/options.json
deleted file mode 100644
index 81dc2c90799f..000000000000
--- a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:12)"
-}
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/options.json b/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/options.json
deleted file mode 100644
index 5f6027f8dd3b..000000000000
--- a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:9)"
-}
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/options.json b/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/options.json
deleted file mode 100644
index b6ff3a4b0987..000000000000
--- a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:4)"
-}
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-class/options.json b/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-class/options.json
deleted file mode 100644
index 4a1b4e5c5cd4..000000000000
--- a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-class/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "throws": "Identifier 'A' has already been declared (2:14)"
-}
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-class/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-class/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-class/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-class/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-class/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-class/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-class/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-class/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-declare-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-declare-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-const-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-const-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-class/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-class/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/output.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/output.json
new file mode 100644
index 000000000000..25358ef97ae7
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-class/output.json
@@ -0,0 +1,147 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 37,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 18
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 37,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 18
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 18,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 18
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 16,
+          "end": 18,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 1,
+              "column": 18
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      },
+      {
+        "type": "DeclareClass",
+        "start": 19,
+        "end": 37,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 18
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 33,
+          "end": 34,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 14
+            },
+            "end": {
+              "line": 2,
+              "column": 15
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "implements": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 35,
+          "end": 37,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 16
+            },
+            "end": {
+              "line": 2,
+              "column": 18
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": [],
+          "internalSlots": [],
+          "exact": false
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-class-declare-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-class-declare-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-func/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-func/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-func/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-func/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-func/output.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-func/output.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-func/output.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-func/output.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-declare-var/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/output.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/output.json
new file mode 100644
index 000000000000..5e5c135d5908
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-declare-var/output.json
@@ -0,0 +1,178 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 50,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 22
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 50,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 22
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareFunction",
+        "start": 0,
+        "end": 27,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 27
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 17,
+          "end": 26,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 17
+            },
+            "end": {
+              "line": 1,
+              "column": 26
+            },
+            "identifierName": "A"
+          },
+          "name": "A",
+          "typeAnnotation": {
+            "type": "TypeAnnotation",
+            "start": 18,
+            "end": 26,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 18
+              },
+              "end": {
+                "line": 1,
+                "column": 26
+              }
+            },
+            "typeAnnotation": {
+              "type": "FunctionTypeAnnotation",
+              "start": 18,
+              "end": 26,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 18
+                },
+                "end": {
+                  "line": 1,
+                  "column": 26
+                }
+              },
+              "typeParameters": null,
+              "params": [],
+              "rest": null,
+              "returnType": {
+                "type": "VoidTypeAnnotation",
+                "start": 22,
+                "end": 26,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 22
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 26
+                  }
+                }
+              }
+            }
+          }
+        },
+        "predicate": null
+      },
+      {
+        "type": "DeclareVariable",
+        "start": 28,
+        "end": 50,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 22
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 40,
+          "end": 49,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 12
+            },
+            "end": {
+              "line": 2,
+              "column": 21
+            },
+            "identifierName": "A"
+          },
+          "name": "A",
+          "typeAnnotation": {
+            "type": "TypeAnnotation",
+            "start": 41,
+            "end": 49,
+            "loc": {
+              "start": {
+                "line": 2,
+                "column": 13
+              },
+              "end": {
+                "line": 2,
+                "column": 21
+              }
+            },
+            "typeAnnotation": {
+              "type": "NumberTypeAnnotation",
+              "start": 43,
+              "end": 49,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 15
+                },
+                "end": {
+                  "line": 2,
+                  "column": 21
+                }
+              }
+            }
+          }
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-func/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/options.json
new file mode 100644
index 000000000000..7c91792f0e9c
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/options.json
@@ -0,0 +1,7 @@
+{
+  "sourceType": "module",
+  "plugins": [
+    "jsx",
+    "flow"
+  ]
+}
diff --git a/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/output.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/output.json
new file mode 100644
index 000000000000..44114ec35913
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-func-func/output.json
@@ -0,0 +1,168 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 43,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 15
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 43,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 15
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "DeclareFunction",
+        "start": 0,
+        "end": 27,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 27
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 17,
+          "end": 26,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 17
+            },
+            "end": {
+              "line": 1,
+              "column": 26
+            },
+            "identifierName": "A"
+          },
+          "name": "A",
+          "typeAnnotation": {
+            "type": "TypeAnnotation",
+            "start": 18,
+            "end": 26,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 18
+              },
+              "end": {
+                "line": 1,
+                "column": 26
+              }
+            },
+            "typeAnnotation": {
+              "type": "FunctionTypeAnnotation",
+              "start": 18,
+              "end": 26,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 18
+                },
+                "end": {
+                  "line": 1,
+                  "column": 26
+                }
+              },
+              "typeParameters": null,
+              "params": [],
+              "rest": null,
+              "returnType": {
+                "type": "VoidTypeAnnotation",
+                "start": 22,
+                "end": 26,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 22
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 26
+                  }
+                }
+              }
+            }
+          }
+        },
+        "predicate": null
+      },
+      {
+        "type": "FunctionDeclaration",
+        "start": 28,
+        "end": 43,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 15
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 37,
+          "end": 38,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 9
+            },
+            "end": {
+              "line": 2,
+              "column": 10
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "generator": false,
+        "async": false,
+        "params": [],
+        "body": {
+          "type": "BlockStatement",
+          "start": 41,
+          "end": 43,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 13
+            },
+            "end": {
+              "line": 2,
+              "column": 15
+            }
+          },
+          "body": [],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-interface-declare-class/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-interface-declare-class/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-interface-declare-class/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-interface-declare-class/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-interface-declare-class/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-interface-declare-class/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-interface-declare-class/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-interface-declare-class/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-declare-var/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-declare-var/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-declare-var/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-declare-var/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-declare-var/output.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-declare-var/output.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-declare-var/output.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-declare-var/output.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-let/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-var-let/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-let/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-let/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-let/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-declare-func-let/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-declare-var-let/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-interface-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-interface-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-interface-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-interface-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-interface-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-interface-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-interface-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-interface-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-class/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-class/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-class/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-class/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-class/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-class/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-class/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-class/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-declare-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-declare-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-let-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-let-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-type-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-type-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-type-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-type-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-type-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-type-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-type-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-type-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-declare-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-declare-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-declare-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-declare-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-declare-interface/options.json
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-interface/input.js b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-interface/input.js
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-interface/input.js
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-interface/input.js
diff --git a/packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-interface/options.json b/packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-interface/options.json
similarity index 100%
rename from packages/babel-parser/test/fixtures/flow/scope/.dupl-decl-var-interface/options.json
rename to packages/babel-parser/test/fixtures/flow/scope/dupl-decl-var-interface/options.json
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/input.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/input.js
index e9ca299ae87e..666d38e3a4ed 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/input.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/input.js
@@ -1,2 +1,2 @@
 declare class foo {}
-const foo = 1;
+const foo1 = 1;
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/output.js
index 9375fc4abd22..0332cc0604b1 100644
--- a/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/output.js
+++ b/packages/babel-plugin-transform-block-scoping/test/fixtures/const-violations/flow-declar/output.js
@@ -1 +1 @@
-var foo = 1;
+var foo1 = 1;
diff --git a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/input.js b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/input.js
index 7c2826479454..64db78b233dc 100644
--- a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/input.js
+++ b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/input.js
@@ -4,13 +4,13 @@ declare function foo(): void
 declare function foo(): void;
 declare function foo<T>(): void;
 declare function foo(x: number, y: string): void;
-declare class A {}
-declare class A<T> extends B<T> { x: number }
-declare class A { static foo(): number, static x : string }
-declare class A { static [ indexer: number]: string }
-declare class A { static () : number }
-declare class A mixins B<T>, C {}
-declare type A = string
+declare class A1 {}
+declare class A1<T> extends B<T> { x: number }
+declare class A1 { static foo(): number, static x : string }
+declare class A1 { static [ indexer: number]: string }
+declare class A1 { static () : number }
+declare class A1 mixins B<T>, C {}
+declare type A2 = string
 declare type T<U> = { [k:string]: U }
-declare interface I { foo: string }
-declare interface I<T> { foo: T }
+declare interface I1 { foo: string }
+declare interface I2<T> { foo: T }
diff --git a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/output.js b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/output.js
index 3be48955c146..3feecb2a9347 100644
--- a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/output.js
+++ b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/output.js
@@ -10,22 +10,22 @@
 
 /*:: declare function foo(x: number, y: string): void;*/
 
-/*:: declare class A {}*/
+/*:: declare class A1 {}*/
 
-/*:: declare class A<T> extends B<T> { x: number }*/
+/*:: declare class A1<T> extends B<T> { x: number }*/
 
-/*:: declare class A { static foo(): number, static x : string }*/
+/*:: declare class A1 { static foo(): number, static x : string }*/
 
-/*:: declare class A { static [ indexer: number]: string }*/
+/*:: declare class A1 { static [ indexer: number]: string }*/
 
-/*:: declare class A { static () : number }*/
+/*:: declare class A1 { static () : number }*/
 
-/*:: declare class A mixins B<T>, C {}*/
+/*:: declare class A1 mixins B<T>, C {}*/
 
-/*:: declare type A = string*/
+/*:: declare type A2 = string*/
 
 /*:: declare type T<U> = { [k:string]: U }*/
 
-/*:: declare interface I { foo: string }*/
+/*:: declare interface I1 { foo: string }*/
 
-/*:: declare interface I<T> { foo: T }*/
+/*:: declare interface I2<T> { foo: T }*/
diff --git a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/def-site-variance/input.js b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/def-site-variance/input.js
index eb188c5c908a..9cc374a5d523 100644
--- a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/def-site-variance/input.js
+++ b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/def-site-variance/input.js
@@ -5,10 +5,10 @@ type T1 = { +p: T }
 type T2 = { -p: T }
 type T3 = { +[k:K]: V }
 type T4 = { -[k:K]: V }
-interface I { +p: T }
-interface I { -p: T }
-interface I { +[k:K]: V }
-interface I { -[k:K]: V }
+interface I1 { +p: T }
+interface I2 { -p: T }
+interface I3 { +[k:K]: V }
+interface I4 { -[k:K]: V }
 declare class I { +p: T }
 declare class I { -p: T }
 declare class I { +[k:K]: V }
diff --git a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-declare-statements/input.js b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-declare-statements/input.js
index 75b24828392c..10cce21e41f8 100644
--- a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-declare-statements/input.js
+++ b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-declare-statements/input.js
@@ -4,14 +4,14 @@ declare function foo(): void
 declare function foo(): void;
 declare function foo<T>(): void;
 declare function foo(x: number, y: string): void;
-declare class A {}
-declare class A<T> extends B<T> { x: number }
-declare class A { static foo(): number; static x : string }
-declare class A { static [ indexer: number]: string }
-declare class A { static () : number }
-declare class A mixins B<T>, C {}
-declare type A = string
+declare class A1 {}
+declare class A1<T> extends B<T> { x: number }
+declare class A1 { static foo(): number; static x : string }
+declare class A1 { static [ indexer: number]: string }
+declare class A1 { static () : number }
+declare class A1 mixins B<T>, C {}
+declare type A2 = string
 declare type T<U> = { [k:string]: U }
-declare interface I { foo: string }
-declare interface I<T> { foo: T }
+declare interface I1 { foo: string }
+declare interface I2<T> { foo: T }
 declare module.exports: string;
diff --git a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-interfaces-module-and-script/input.js b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-interfaces-module-and-script/input.js
index 2e37dfaf618d..1ee5de6c9ea3 100644
--- a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-interfaces-module-and-script/input.js
+++ b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-interfaces-module-and-script/input.js
@@ -1,7 +1,7 @@
-interface A {}
-interface A extends B {}
-interface A<T> extends B<T>, C<T> {}
-interface A { foo: () => number; }
+interface A1 {}
+interface A2 extends B {}
+interface A3<T> extends B<T>, C<T> {}
+interface A4 { foo: () => number; }
 interface Dictionary { [index: string]: string; length: number; }
 class Foo implements Bar {}
 class Foo2 extends Bar implements Bat, Man<number> {}
diff --git a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js
index 741c23987d23..7a1d4011b35a 100644
--- a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js
+++ b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js
@@ -6,10 +6,10 @@ declare class A {
   @@asyncIterator(): Iterator<File>;
 }
 
-interface A {
+interface A1 {
   @@iterator(): Iterator<File>;
 }
 
-interface A {
+interface A2 {
   @@asyncIterator(): Iterator<File>;
 }
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/input.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/input.mjs
new file mode 100644
index 000000000000..d2e9958f6aaf
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/input.mjs
@@ -0,0 +1,4 @@
+function f(): void;
+function f(): void {
+}
+export { f }
\ No newline at end of file
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/options.json b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/options.json
new file mode 100644
index 000000000000..d5e8a7e4201b
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/options.json
@@ -0,0 +1,4 @@
+{
+  "plugins": ["transform-typescript"],
+  "sourceType": "module"
+}
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/output.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/output.mjs
new file mode 100644
index 000000000000..a7997dca3a66
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/function/overloads-exports/output.mjs
@@ -0,0 +1,3 @@
+function f() {}
+
+export { f };