stupidly check for variable types

typescript-eslint · Apr 24, 2024 · e57985a · e57985a
1 parent 26e7be7
commit e57985a
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diff --git a/packages/eslint-plugin/src/rules/require-types-exports.ts b/packages/eslint-plugin/src/rules/require-types-exports.ts
@@ -1,3 +1,4 @@
+import type { Reference } from '@typescript-eslint/scope-manager';
 import { DefinitionType } from '@typescript-eslint/scope-manager';
 import type { TSESTree } from '@typescript-eslint/utils';
 import { AST_NODE_TYPES } from '@typescript-eslint/utils';
@@ -12,6 +13,12 @@ type FunctionNode =
   | TSESTree.ArrowFunctionExpression
   | TSESTree.FunctionExpression;
 
+type TypeReference = Reference & {
+  identifier: {
+    parent: TSESTree.TSTypeReference;
+  };
+};
+
 export default createRule<[], MessageIds>({
   name: 'require-types-exports',
   meta: {
@@ -28,9 +35,23 @@ export default createRule<[], MessageIds>({
   },
   defaultOptions: [],
   create(context) {
+    const typeReferences = new Set<TypeReference>();
     const externalizedTypes = new Set<string>();
     const reportedTypes = new Set<string>();
 
+    function collectTypeReferences(node: TSESTree.Program): void {
+      const scope = context.sourceCode.getScope(node);
+
+      scope.references.forEach(r => {
+        if (
+          r.resolved?.isTypeVariable &&
+          r.identifier.parent.type === AST_NODE_TYPES.TSTypeReference
+        ) {
+          typeReferences.add(r as TypeReference);
+        }
+      });
+    }
+
     function collectImportedTypes(node: TSESTree.ImportSpecifier): void {
       externalizedTypes.add(node.local.name);
     }
@@ -60,6 +81,8 @@ export default createRule<[], MessageIds>({
       for (const declaration of node.declaration.declarations) {
         if (declaration.init?.type === AST_NODE_TYPES.ArrowFunctionExpression) {
           checkFunctionTypes(declaration.init);
+        } else {
+          checkVariableTypes(declaration);
         }
       }
     }
@@ -107,6 +130,21 @@ export default createRule<[], MessageIds>({
         .forEach(checkTypeNode);
     }
 
+    function checkVariableTypes(
+      node: TSESTree.LetOrConstOrVarDeclarator,
+    ): void {
+      if (node.id.type !== AST_NODE_TYPES.Identifier) {
+        return;
+      }
+
+      typeReferences.forEach(r => {
+        // TODO: Probably not the best way to do it...
+        if (isLocationOverlapping(r.identifier.loc, node.loc)) {
+          checkTypeNode(r.identifier.parent);
+        }
+      });
+    }
+
     function checkTypeNode(node: TSESTree.TSTypeReference): void {
       const name = getTypeName(node);
 
@@ -141,7 +179,37 @@ export default createRule<[], MessageIds>({
       return '';
     }
 
+    function isLocationOverlapping(
+      location: TSESTree.Node['loc'],
+      container: TSESTree.Node['loc'],
+    ): boolean {
+      if (
+        location.start.line < container.start.line ||
+        location.end.line > container.end.line
+      ) {
+        return false;
+      }
+
+      if (
+        location.start.line === container.start.line &&
+        location.start.column < container.start.column
+      ) {
+        return false;
+      }
+
+      if (
+        location.end.line === container.end.line &&
+        location.end.column > container.end.column
+      ) {
+        return false;
+      }
+
+      return true;
+    }
+
     return {
+      Program: collectTypeReferences,
+
       'ImportDeclaration ImportSpecifier, ImportSpecifier':
         collectImportedTypes,
 

diff --git a/packages/eslint-plugin/tests/rules/require-types-exports.test.ts b/packages/eslint-plugin/tests/rules/require-types-exports.test.ts
@@ -303,6 +303,24 @@ ruleTester.run('require-types-exports', rule, {
         return value;
       }
     `,
+
+    `
+      import type { A } from './types';
+
+      export type T1 = number;
+
+      export interface T2 {
+        key: number;
+      }
+
+      export const value: { a: { b: { c: T1 } } } | [string, T2 | A] = {
+        a: {
+          b: {
+            c: 1,
+          },
+        },
+      };
+    `,
   ],
 
   invalid: [
@@ -1739,5 +1757,45 @@ ruleTester.run('require-types-exports', rule, {
         },
       ],
     },
+
+    {
+      code: `
+        import type { A } from './types';
+
+        type T1 = number;
+
+        interface T2 {
+          key: number;
+        }
+
+        export const value: { a: { b: { c: T1 } } } | [string, T2 | A] = {
+          a: {
+            b: {
+              c: 1,
+            },
+          },
+        };
+      `,
+      errors: [
+        {
+          messageId: 'requireTypeExport',
+          line: 10,
+          column: 44,
+          endColumn: 46,
+          data: {
+            name: 'T1',
+          },
+        },
+        {
+          messageId: 'requireTypeExport',
+          line: 10,
+          column: 64,
+          endColumn: 66,
+          data: {
+            name: 'T2',
+          },
+        },
+      ],
+    },
   ],
 });