Correctly detect used/unused namespace exports that begin with double underscores (#1180)

Co-authored-by: Andrew Kallem <[email protected]>

Author: akallem

packages/knip/fixtures/exports-special-characters/exports.ts

@@ -1,6 +1,7 @@
 export const $dollar = '$';
 export const dollar$ = '$$';
 export const _underscore = '_';
+export const __underscores = '__';
 
 export class DollarMembers {
   $member: string;

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/imported.ts

@@ -0,0 +1,2 @@
+export const __underscoresUnused = 'underscoresUnused';
+export const __underscoresUsed = 'underscoresUsed';

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/index.ts

@@ -0,0 +1,5 @@
+import { __underscoresUsed } from './imported';
+import * as NS from './namespace';
+
+__underscoresUsed;
+NS.__underscoresUsed;

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/knip.json

@@ -0,0 +1,3 @@
+{
+  "ignoreExportsUsedInFile": true
+}

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/namespace.ts

@@ -0,0 +1,2 @@
+export const __underscoresUnused = 'underscoresUnused';
+export const __underscoresUsed = 'underscoresUsed';

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/package.json

@@ -0,0 +1,3 @@
+{
+  "name": "@fixtures/ignore-exports-used-in-file-id-underscores"
+}

packages/knip/fixtures/ignore-exports-used-in-file-id-underscores/tsconfig.json

@@ -0,0 +1,5 @@
+{
+  "compilerOptions": {
+    "types": ["node"]
+  }
+}

packages/knip/src/typescript/ast-helpers.ts

@@ -181,7 +181,7 @@ const getMemberStringLiterals = (typeChecker: ts.TypeChecker, node: ts.Node) =>
   }
 
   if (ts.isPropertyAccessExpression(node)) {
-    return [node.name.escapedText as string];
+    return [node.name.getText()];
   }
 };
 

packages/knip/test/exports-special-characters.test.ts

@@ -16,6 +16,7 @@ test('Handle special characters in named exports and members', async () => {
   assert(issues.exports['exports.ts']['$dollar']);
   assert(issues.exports['exports.ts']['dollar$']);
   assert(issues.exports['exports.ts']['_underscore']);
+  assert(issues.exports['exports.ts']['__underscores']);
   assert(issues.exports['exports.ts']['$Dollar']);
 
   assert(issues.types['exports.ts']['$DollarType']);
@@ -28,7 +29,7 @@ test('Handle special characters in named exports and members', async () => {
   assert.deepEqual(counters, {
     ...baseCounters,
     classMembers: 4,
-    exports: 4,
+    exports: 5,
     types: 1,
     processed: 2,
     total: 2,
@@ -45,6 +46,7 @@ test('Handle special characters in named exports and members (nsTypes)', async (
   assert(issues.exports['exports.ts']['$dollar']);
   assert(issues.exports['exports.ts']['dollar$']);
   assert(issues.exports['exports.ts']['_underscore']);
+  assert(issues.exports['exports.ts']['__underscores']);
   assert(issues.exports['exports.ts']['$Dollar']);
 
   assert(issues.types['exports.ts']['$DollarType']);
@@ -79,7 +81,7 @@ test('Handle special characters in named exports and members (nsTypes)', async (
     ...baseCounters,
     classMembers: 4,
     enumMembers: 20,
-    exports: 4,
+    exports: 5,
     types: 1,
     processed: 2,
     total: 2,

packages/knip/test/ignore-exports-used-in-file-id-underscores.test.ts

@@ -0,0 +1,25 @@
+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/ignore-exports-used-in-file-id-underscores');
+
+test('Find unused exports when identifiers begin with two underscores', async () => {
+  const { issues, counters } = await main({
+    ...baseArguments,
+    cwd,
+  });
+
+  assert.equal(issues.exports['imported.ts']['__underscoresUnused'].symbol, '__underscoresUnused');
+  assert.equal(issues.exports['namespace.ts']['__underscoresUnused'].symbol, '__underscoresUnused');
+
+  assert.deepEqual(counters, {
+    ...baseCounters,
+    exports: 2,
+    processed: 3,
+    total: 3,
+  });
+});