feat(parser): Add support for class static initialization block

meriyah · May 7, 2022 · 1510e36 · 1510e36
1 parent 2ea3869
commit 1510e36
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Showing 3 changed files with 199 additions and 5 deletions.
diff --git a/src/estree.ts b/src/estree.ts
@@ -117,6 +117,7 @@ export type Node =
   | ReturnStatement
   | SequenceExpression
   | SpreadElement
+  | StaticBlock
   | Super
   | SwitchCase
   | SwitchStatement
@@ -274,6 +275,10 @@ interface MethodDefinitionBase extends _Node {
   decorators?: Decorator[];
 }
 
+export interface BlockStatementBase extends _Node {
+  body: Statement[];
+}
+
 export interface ArrayExpression extends _Node {
   type: 'ArrayExpression';
   elements: (Expression | SpreadElement | null)[];
@@ -321,9 +326,8 @@ export interface BinaryExpression extends _Node {
   right: Expression;
 }
 
-export interface BlockStatement extends _Node {
+export interface BlockStatement extends BlockStatementBase {
   type: 'BlockStatement';
-  body: Statement[];
 }
 
 export interface BreakStatement extends _Node {
@@ -354,9 +358,13 @@ export interface CatchClause extends _Node {
   body: BlockStatement;
 }
 
+export interface StaticBlock extends BlockStatementBase {
+  type: 'StaticBlock';
+}
+
 export interface ClassBody extends _Node {
   type: 'ClassBody';
-  body: (ClassElement | PropertyDefinition)[];
+  body: (ClassElement | PropertyDefinition | StaticBlock)[];
 }
 
 export interface PropertyDefinition extends _Node {

diff --git a/src/parser.ts b/src/parser.ts
@@ -1770,6 +1770,41 @@ export function parseCatchBlock(
   });
 }
 
+/**
+ * Parses class static initialization block
+ *
+ * @see [Link](https://github.com/tc39/proposal-class-static-block)
+ *
+ * @param parser Parser object
+ * @param context Context masks
+ * @param scope Scope instance
+ * @param start Start pos of node
+ * @param line
+ * @param column
+ */
+export function parseStaticBlock(
+  parser: ParserState,
+  context: Context,
+  scope: ScopeState | undefined,
+  start: number,
+  line: number,
+  column: number
+): ESTree.StaticBlock {
+  // StaticBlock ::
+  //   '{' StatementList '}'
+
+  if (scope) scope = addChildScope(scope, ScopeKind.Block);
+
+  const ctorContext = Context.InClass | Context.SuperCall;
+  context = ((context | ctorContext) ^ ctorContext) | Context.SuperProperty;
+  const { body } = parseBlock(parser, context, scope, {}, start, line, column);
+
+  return finishNode(parser, context, start, line, column, {
+    type: 'StaticBlock',
+    body
+  });
+}
+
 /**
  * Parses do while statement
  *
@@ -8163,7 +8198,7 @@ export function parseClassBody(
   context = (context | Context.DisallowIn) ^ Context.DisallowIn;
   parser.flags = (parser.flags | Flags.HasConstructor) ^ Flags.HasConstructor;
 
-  const body: (ESTree.MethodDefinition | ESTree.PropertyDefinition)[] = [];
+  const body: (ESTree.MethodDefinition | ESTree.PropertyDefinition | ESTree.StaticBlock)[] = [];
   let decorators: ESTree.Decorator[];
 
   while (parser.token !== Token.RightBrace) {
@@ -8231,7 +8266,7 @@ function parseClassElementList(
   start: number,
   line: number,
   column: number
-): ESTree.MethodDefinition | ESTree.PropertyDefinition {
+): ESTree.MethodDefinition | ESTree.PropertyDefinition | ESTree.StaticBlock {
   let kind: PropertyKind = isStatic ? PropertyKind.Static : PropertyKind.None;
   let key: ESTree.Expression | ESTree.PrivateIdentifier | null = null;
 
@@ -8302,6 +8337,8 @@ function parseClassElementList(
     key = parsePrivateIdentifier(parser, context | Context.InClass, tokenPos, linePos, colPos);
   } else if (context & Context.OptionsNext && (parser.token & Token.IsClassField) === Token.IsClassField) {
     kind |= PropertyKind.ClassField;
+  } else if (context & Context.OptionsNext && isStatic && token === Token.LeftBrace) {
+    return parseStaticBlock(parser, context, scope, tokenPos, linePos, colPos);
   } else if (token === Token.EscapedFutureReserved) {
     key = parseIdentifier(parser, context, 0);
     if (parser.token !== Token.LeftParen)

diff --git a/test/parser/next/static-block.ts b/test/parser/next/static-block.ts
@@ -0,0 +1,149 @@
+import { Context } from '../../../src/common';
+import { pass, fail } from '../../test-utils';
+
+describe('Next - Class static initialization block', () => {
+  fail('Next - Class static initialization block (fail)', [
+    ['class A { static {} }', Context.OptionsWebCompat],
+    ['class A { static {} }', Context.None],
+    ['class A { static { super() } }', Context.OptionsNext],
+    ['class A {}; class B extends A { static { super() } }', Context.OptionsNext],
+    ['class A { static async {} }', Context.OptionsNext],
+    ['class A { async static {} }', Context.OptionsNext]
+  ]);
+
+  pass('Next - Class static initialization block (pass)', [
+    [
+      `class A { static {} }`,
+      Context.OptionsNext,
+      {
+        body: [
+          {
+            body: {
+              body: [
+                {
+                  body: [],
+                  type: 'StaticBlock'
+                }
+              ],
+              type: 'ClassBody'
+            },
+            decorators: [],
+            id: {
+              name: 'A',
+              type: 'Identifier'
+            },
+            superClass: null,
+            type: 'ClassDeclaration'
+          }
+        ],
+        sourceType: 'script',
+        type: 'Program'
+      }
+    ],
+    [
+      `class A { static { this.a } }`,
+      Context.OptionsNext,
+      {
+        body: [
+          {
+            body: {
+              body: [
+                {
+                  body: [
+                    {
+                      expression: {
+                        computed: false,
+                        object: {
+                          type: 'ThisExpression'
+                        },
+                        property: {
+                          name: 'a',
+                          type: 'Identifier'
+                        },
+                        type: 'MemberExpression'
+                      },
+                      type: 'ExpressionStatement'
+                    }
+                  ],
+                  type: 'StaticBlock'
+                }
+              ],
+              type: 'ClassBody'
+            },
+            decorators: [],
+            id: {
+              name: 'A',
+              type: 'Identifier'
+            },
+            superClass: null,
+            type: 'ClassDeclaration'
+          }
+        ],
+        sourceType: 'script',
+        type: 'Program'
+      }
+    ],
+    [
+      `class A {}; class B extends A { static { super.a } }`,
+      Context.OptionsNext,
+      {
+        body: [
+          {
+            body: {
+              body: [],
+              type: 'ClassBody'
+            },
+            decorators: [],
+            id: {
+              name: 'A',
+              type: 'Identifier'
+            },
+            superClass: null,
+            type: 'ClassDeclaration'
+          },
+          {
+            type: 'EmptyStatement'
+          },
+          {
+            body: {
+              body: [
+                {
+                  body: [
+                    {
+                      expression: {
+                        computed: false,
+                        object: {
+                          type: 'Super'
+                        },
+                        property: {
+                          name: 'a',
+                          type: 'Identifier'
+                        },
+                        type: 'MemberExpression'
+                      },
+                      type: 'ExpressionStatement'
+                    }
+                  ],
+                  type: 'StaticBlock'
+                }
+              ],
+              type: 'ClassBody'
+            },
+            decorators: [],
+            id: {
+              name: 'B',
+              type: 'Identifier'
+            },
+            superClass: {
+              name: 'A',
+              type: 'Identifier'
+            },
+            type: 'ClassDeclaration'
+          }
+        ],
+        sourceType: 'script',
+        type: 'Program'
+      }
+    ]
+  ]);
+});