From e42b09d9cf13ecde2fc7449cb7ec76fc1968cddb Mon Sep 17 00:00:00 2001
From: Lars Kappert <lars@webpro.nl>
Date: Sun, 23 Feb 2025 10:37:49 +0100
Subject: [PATCH] Defer resolve entry points in webpack plugin (resolves #949)

---
 .../plugins/webpack/src/{app.ts => app.tsx}   |  0
 .../webpack/src/{vendor.ts => vendor.js}      |  0
 .../fixtures/plugins/webpack/webpack.dev.js   |  4 +--
 .../fixtures/plugins/webpack2/entry.dev.js    |  0
 .../fixtures/plugins/webpack2/entry.prod.js   |  0
 .../node_modules/webpack-cli/index.js         |  0
 .../node_modules/webpack-cli/package.json     |  4 +++
 .../webpack2/node_modules/webpack/index.js    |  6 ++++
 .../node_modules/webpack/package.json         |  9 +++++
 .../fixtures/plugins/webpack2/package.json    | 12 +++++++
 .../fixtures/plugins/webpack2/webpack.dev.js  |  8 +++++
 .../fixtures/plugins/webpack2/webpack.prod.js |  8 +++++
 packages/knip/src/plugins/webpack/index.ts    |  9 ++---
 packages/knip/test/plugins/webpack2.test.ts   | 35 +++++++++++++++++++
 14 files changed, 89 insertions(+), 6 deletions(-)
 rename packages/knip/fixtures/plugins/webpack/src/{app.ts => app.tsx} (100%)
 rename packages/knip/fixtures/plugins/webpack/src/{vendor.ts => vendor.js} (100%)
 create mode 100644 packages/knip/fixtures/plugins/webpack2/entry.dev.js
 create mode 100644 packages/knip/fixtures/plugins/webpack2/entry.prod.js
 create mode 100644 packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/index.js
 create mode 100644 packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/package.json
 create mode 100644 packages/knip/fixtures/plugins/webpack2/node_modules/webpack/index.js
 create mode 100644 packages/knip/fixtures/plugins/webpack2/node_modules/webpack/package.json
 create mode 100644 packages/knip/fixtures/plugins/webpack2/package.json
 create mode 100644 packages/knip/fixtures/plugins/webpack2/webpack.dev.js
 create mode 100644 packages/knip/fixtures/plugins/webpack2/webpack.prod.js
 create mode 100644 packages/knip/test/plugins/webpack2.test.ts

diff --git a/packages/knip/fixtures/plugins/webpack/src/app.ts b/packages/knip/fixtures/plugins/webpack/src/app.tsx
similarity index 100%
rename from packages/knip/fixtures/plugins/webpack/src/app.ts
rename to packages/knip/fixtures/plugins/webpack/src/app.tsx
diff --git a/packages/knip/fixtures/plugins/webpack/src/vendor.ts b/packages/knip/fixtures/plugins/webpack/src/vendor.js
similarity index 100%
rename from packages/knip/fixtures/plugins/webpack/src/vendor.ts
rename to packages/knip/fixtures/plugins/webpack/src/vendor.js
diff --git a/packages/knip/fixtures/plugins/webpack/webpack.dev.js b/packages/knip/fixtures/plugins/webpack/webpack.dev.js
index 38a32b296..25c536a58 100644
--- a/packages/knip/fixtures/plugins/webpack/webpack.dev.js
+++ b/packages/knip/fixtures/plugins/webpack/webpack.dev.js
@@ -6,8 +6,8 @@ module.exports = env =>
   merge(common(), {
     mode: env.production ? 'production' : 'development',
     entry: {
-      main: './src/app.ts',
-      vendor: './src/vendor.ts',
+      main: './src/app',
+      vendor: './src/vendor',
     },
     module: {
       rules: [
diff --git a/packages/knip/fixtures/plugins/webpack2/entry.dev.js b/packages/knip/fixtures/plugins/webpack2/entry.dev.js
new file mode 100644
index 000000000..e69de29bb
diff --git a/packages/knip/fixtures/plugins/webpack2/entry.prod.js b/packages/knip/fixtures/plugins/webpack2/entry.prod.js
new file mode 100644
index 000000000..e69de29bb
diff --git a/packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/index.js b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/index.js
new file mode 100644
index 000000000..e69de29bb
diff --git a/packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/package.json b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/package.json
new file mode 100644
index 000000000..4d09795ef
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack-cli/package.json
@@ -0,0 +1,4 @@
+{
+  "name": "webpack-cli",
+  "bin": "index.js"
+}
diff --git a/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/index.js b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/index.js
new file mode 100644
index 000000000..41eaf00bf
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/index.js
@@ -0,0 +1,6 @@
+const webpack = {
+  DefinePlugin: class DefinePlugin {},
+  ProvidePlugin: class ProvidePlugin {},
+};
+
+module.exports = webpack;
diff --git a/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/package.json b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/package.json
new file mode 100644
index 000000000..094967d4c
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/node_modules/webpack/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "webpack",
+  "bin": "index.js",
+  "peerDependenciesMeta": {
+    "webpack-cli": {
+      "optional": true
+    }
+  }
+}
diff --git a/packages/knip/fixtures/plugins/webpack2/package.json b/packages/knip/fixtures/plugins/webpack2/package.json
new file mode 100644
index 000000000..4f6268657
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/package.json
@@ -0,0 +1,12 @@
+{
+  "name": "@fixtures/webpack2",
+  "scripts": {
+    "dev": "webpack --config webpack.dev.js",
+    "prod": "webpack --config webpack.prod.js"
+  },
+  "dependencies": {},
+  "devDependencies": {
+    "webpack": "*",
+    "webpack-cli": "*"
+  }
+}
diff --git a/packages/knip/fixtures/plugins/webpack2/webpack.dev.js b/packages/knip/fixtures/plugins/webpack2/webpack.dev.js
new file mode 100644
index 000000000..974ec9d08
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/webpack.dev.js
@@ -0,0 +1,8 @@
+import 'webpack';
+
+export default () => {
+  return {
+    mode: 'development',
+    entry: './entry.dev.js',
+  };
+};
diff --git a/packages/knip/fixtures/plugins/webpack2/webpack.prod.js b/packages/knip/fixtures/plugins/webpack2/webpack.prod.js
new file mode 100644
index 000000000..3d57b25e7
--- /dev/null
+++ b/packages/knip/fixtures/plugins/webpack2/webpack.prod.js
@@ -0,0 +1,8 @@
+import 'webpack';
+
+export default () => {
+  return {
+    mode: 'production',
+    entry: './entry.prod.js',
+  };
+};
diff --git a/packages/knip/src/plugins/webpack/index.ts b/packages/knip/src/plugins/webpack/index.ts
index d3fc96a79..a76cb87ac 100644
--- a/packages/knip/src/plugins/webpack/index.ts
+++ b/packages/knip/src/plugins/webpack/index.ts
@@ -4,10 +4,10 @@ import { compact } from '../../util/array.js';
 import {
   type Input,
   toDeferResolve,
+  toDeferResolveEntry,
+  toDeferResolveProductionEntry,
   toDependency,
   toDevDependency,
-  toEntry,
-  toProductionEntry,
 } from '../../util/input.js';
 import { isAbsolute, isInternal, join, relative } from '../../util/path.js';
 import { hasDependency } from '../../util/plugin.js';
@@ -99,8 +99,9 @@ export const findWebpackDependenciesFromConfig = async ({ config, cwd }: { confi
         } else {
           const absoluteEntry = isAbsolute(entry) ? entry : join(options.context ? options.context : cwd, entry);
           const item = relative(cwd, absoluteEntry);
-          const value = options.mode === 'development' ? toEntry(item) : toProductionEntry(item);
-          inputs.add(value);
+          const input =
+            options.mode === 'development' ? toDeferResolveEntry(item) : toDeferResolveProductionEntry(item);
+          inputs.add(input);
         }
       }
     }
diff --git a/packages/knip/test/plugins/webpack2.test.ts b/packages/knip/test/plugins/webpack2.test.ts
new file mode 100644
index 000000000..ba50b9bf0
--- /dev/null
+++ b/packages/knip/test/plugins/webpack2.test.ts
@@ -0,0 +1,35 @@
+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/plugins/webpack2');
+
+test('Find dependencies with Webpack plugin (2)', async () => {
+  const { counters } = await main({
+    ...baseArguments,
+    cwd,
+  });
+
+  assert.deepEqual(counters, {
+    ...baseCounters,
+    processed: 4,
+    total: 4,
+  });
+});
+
+test('Find dependencies with Webpack plugin (2) (production)', async () => {
+  const { counters } = await main({
+    ...baseArguments,
+    cwd,
+    isProduction: true,
+  });
+
+  assert.deepEqual(counters, {
+    ...baseCounters,
+    processed: 1,
+    total: 1,
+  });
+});