Consider module.exports = require() to be re-exports

webpro-nl · Sep 23, 2024 · e2bdb95 · e2bdb95
1 parent e40f618
commit e2bdb95
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Showing 9 changed files with 66 additions and 5 deletions.
diff --git a/packages/knip/fixtures/re-exports-cjs/1-entry.js b/packages/knip/fixtures/re-exports-cjs/1-entry.js
@@ -0,0 +1,6 @@
+const { something } = require('./2-re-export-star');
+something;
+
+module.exports.somethingToIgnore = require('./2-re-export-star').somethingToIgnore;
+
+module.exports.somethingNotToIgnore = require('./2-re-export-star').somethingNotToIgnore;
diff --git a/packages/knip/fixtures/re-exports-cjs/2-re-export-star.js b/packages/knip/fixtures/re-exports-cjs/2-re-export-star.js
@@ -0,0 +1 @@
+module.exports = require('./3-my-module');
diff --git a/packages/knip/fixtures/re-exports-cjs/3-my-module.js b/packages/knip/fixtures/re-exports-cjs/3-my-module.js
@@ -0,0 +1,3 @@
+module.exports.something = {};
+module.exports.somethingToIgnore = {};
+module.exports.somethingNotToIgnore = {};
diff --git a/packages/knip/fixtures/re-exports-cjs/package.json b/packages/knip/fixtures/re-exports-cjs/package.json
@@ -0,0 +1,7 @@
+{
+  "name": "@fixtures/re-exports-cjs",
+  "knip": {
+    "entry": ["1-entry.js"],
+    "project": ["*.js"]
+  }
+}
diff --git a/packages/knip/src/typescript/ast-helpers.ts b/packages/knip/src/typescript/ast-helpers.ts
@@ -218,3 +218,11 @@ export const getExportKeywordNode = (node: ts.Node) =>
 export const getDefaultKeywordNode = (node: ts.Node) =>
   // @ts-expect-error Property 'modifiers' does not exist on type 'Node'.
   (node.modifiers as ts.Modifier[])?.find(mod => mod.kind === ts.SyntaxKind.DefaultKeyword);
+
+export const hasRequireCall = (node: ts.Node): boolean => {
+  if (ts.isCallExpression(node) && ts.isIdentifier(node.expression) && node.expression.text === 'require') return true;
+  return node.getChildren().some(child => hasRequireCall(child));
+};
+
+export const isModuleExportsAccess = (node: ts.PropertyAccessExpression) =>
+  ts.isIdentifier(node.expression) && node.expression.escapedText === 'module' && node.name.escapedText === 'exports';
diff --git a/packages/knip/src/typescript/get-imports-and-exports.ts b/packages/knip/src/typescript/get-imports-and-exports.ts
@@ -120,6 +120,7 @@ const getImportsAndExports = (
         // Patterns:
         // export { id } from 'specifier';
         // export * from 'specifier';
+        // module.exports = require('specifier');
         addValue(imports.reExported, identifier, sourceFile.fileName);
       }
     } else {

diff --git a/packages/knip/src/typescript/visitors/dynamic-imports/requireCall.ts b/packages/knip/src/typescript/visitors/dynamic-imports/requireCall.ts
@@ -1,5 +1,6 @@
 import ts from 'typescript';
-import { findAncestor, findDescendants, isRequireCall, isTopLevel } from '../../ast-helpers.js';
+import { IMPORT_STAR } from '../../../constants.js';
+import { findAncestor, findDescendants, isModuleExportsAccess, isRequireCall, isTopLevel } from '../../ast-helpers.js';
 import { isNotJS } from '../helpers.js';
 import { importVisitor as visit } from '../index.js';
 
@@ -56,6 +57,16 @@ export default visit(
             // Pattern: require('specifier')
             return { identifier: 'default', specifier, pos: node.arguments[0].pos, resolve };
           }
+
+          if (
+            ts.isBinaryExpression(node.parent) &&
+            ts.isPropertyAccessExpression(node.parent.left) &&
+            isModuleExportsAccess(node.parent.left)
+          ) {
+            // Pattern: module.exports = require('specifier')
+            return { identifier: IMPORT_STAR, specifier, isReExport: true, pos: node.arguments[0].pos };
+          }
+
           // Pattern: require('side-effects')
           return { identifier: 'default', specifier, pos: node.arguments[0].pos, resolve };
         }

diff --git a/packages/knip/src/typescript/visitors/exports/moduleExportsAccessExpression.ts b/packages/knip/src/typescript/visitors/exports/moduleExportsAccessExpression.ts
@@ -1,13 +1,10 @@
 import ts from 'typescript';
 import type { Fix } from '../../../types/exports.js';
 import { SymbolType } from '../../../types/issues.js';
-import { stripQuotes } from '../../ast-helpers.js';
+import { hasRequireCall, isModuleExportsAccess, stripQuotes } from '../../ast-helpers.js';
 import { isJS } from '../helpers.js';
 import { exportVisitor as visit } from '../index.js';
 
-const isModuleExportsAccess = (node: ts.PropertyAccessExpression) =>
-  ts.isIdentifier(node.expression) && node.expression.escapedText === 'module' && node.name.escapedText === 'exports';
-
 export default visit(isJS, (node, { isFixExports }) => {
   if (ts.isExpressionStatement(node)) {
     if (ts.isBinaryExpression(node.expression)) {
@@ -37,6 +34,12 @@ export default visit(isJS, (node, { isFixExports }) => {
               return { node, identifier: node.getText(), type: SymbolType.UNKNOWN, pos: node.getStart(), fix };
             });
           }
+
+          if (ts.isCallExpression(node.expression.right) && hasRequireCall(node.expression.right)) {
+            // Pattern: module.exports = require('specifier');
+            return;
+          }
+
           // Pattern: module.exports = any
           return { node, identifier: 'default', type: SymbolType.UNKNOWN, pos: expr.pos + 1, fix: undefined };
         }

diff --git a/packages/knip/test/re-exports-cjs.test.ts b/packages/knip/test/re-exports-cjs.test.ts
@@ -0,0 +1,21 @@
+import { test } from 'bun:test';
+import assert from 'node:assert/strict';
+import { main } from '../src/index.js';
+import { resolve } from '../src/util/path.js';
+import baseArguments from './helpers/baseArguments.js';
+import baseCounters from './helpers/baseCounters.js';
+
+const cwd = resolve('fixtures/re-exports-cjs');
+
+test('Ignore re-exports from entry files (CommonJS', async () => {
+  const { counters } = await main({
+    ...baseArguments,
+    cwd,
+  });
+
+  assert.deepEqual(counters, {
+    ...baseCounters,
+    processed: 3,
+    total: 3,
+  });
+});