Track Angular polyfills (#913)

packages/knip/fixtures/plugins/angular/angular.json

@@ -20,9 +20,7 @@
             "outputPath": "dist/knip-angular-example",
             "index": "src/index.html",
             "main": "src/main.ts",
-            "polyfills": [
-              "zone.js"
-            ],
+            "polyfills": "src/polyfill.js",
             "tsConfig": "tsconfig.app.json",
             "inlineStyleLanguage": "scss",
             "assets": [
@@ -103,4 +101,4 @@
       }
     }
   }
-}
+}

packages/knip/fixtures/plugins/angular/package.json

@@ -8,6 +8,9 @@
     "watch": "ng build --watch --configuration development",
     "test": "ng test"
   },
+  "dependencies": {
+    "zone.js": "*"
+  },
   "devDependencies": {
     "@angular/cli": "*",
     "karma": "*",

packages/knip/fixtures/plugins/angular2/angular.json

@@ -105,4 +105,4 @@
       }
     }
   }
-}
+}

packages/knip/fixtures/plugins/angular2/package.json

@@ -3,6 +3,9 @@
   "scripts": {
     "ng": "ng"
   },
+  "dependencies": {
+    "zone.js": "*"
+  },
   "devDependencies": {
     "@angular/cli": "*",
     "@angular/ssr": "*",

packages/knip/fixtures/plugins/angular3/angular.json

@@ -16,15 +16,19 @@
             "ssr": {
               "entry": "src/server.ts"
             },
-            "server": "src/main.server-for-non-prod.ts"
+            "server": "src/main.server-for-non-prod.ts",
+            "polyfills": [
+              "src/polyfill.js"
+            ]
           },
           "configurations": {
             "production": {
               "server": "src/main.server.ts",
               "scripts": ["src/script.js"]
             },
             "development": {
-              "scripts": ["src/script-for-non-prod.js"]
+              "scripts": ["src/script-for-non-prod.js"],
+              "polyfills": ["src/polyfill-for-non-prod.js"]
             }
           }
         },
@@ -43,4 +47,4 @@
       }
     }
   }
-}
+}

packages/knip/src/plugins/angular/index.ts

@@ -1,6 +1,7 @@
+import { existsSync } from 'node:fs';
 import type { IsPluginEnabled, Plugin, ResolveConfig } from '../../types/config.js';
-import { type Input, toConfig, toDependency, toEntry, toProductionEntry } from '../../util/input.js';
-import { join } from '../../util/path.js';
+import { type Input, toConfig, toDeferResolve, toDependency, toEntry, toProductionEntry } from '../../util/input.js';
+import { isInternal, join } from '../../util/path.js';
 import { hasDependency } from '../../util/plugin.js';
 import * as karma from '../karma/helpers.js';
 import type {
@@ -44,24 +45,37 @@ const resolveConfig: ResolveConfig<AngularCLIWorkspaceConfiguration> = async (co
       );
       const productionEntriesByOption: EntriesByOption =
         entriesByOptionByConfig.get(PRODUCTION_CONFIG_NAME) ?? new Map();
-      const normalizePath = (path: string) => join(cwd, path);
+      const isBuildTarget = targetName === BUILD_TARGET_NAME;
+      const maybeExternal = (option: string) => option === 'polyfills';
+      const toInput = (specifier: string, opts: { isProduction: boolean; maybeExternal: boolean }): Input => {
+        const normalizedPath = join(cwd, specifier);
+        // 👇 `isInternal` will report `false` for specifiers not starting with `.`
+        //    However, relative imports are usually specified in `angular.json` without `.` prefix
+        //    Hence checking also that file doesn't exist before considering it external
+        if (opts.maybeExternal && !isInternal(specifier) && !existsSync(normalizedPath)) {
+          return toDeferResolve(specifier);
+        }
+        return opts.isProduction ? toProductionEntry(normalizedPath) : toEntry(normalizedPath);
+      };
       for (const [configName, entriesByOption] of entriesByOptionByConfig.entries()) {
-        for (const entries of entriesByOption.values()) {
+        for (const [option, entries] of entriesByOption.entries()) {
           for (const entry of entries) {
             inputs.add(
-              targetName === BUILD_TARGET_NAME && configName === PRODUCTION_CONFIG_NAME
-                ? toProductionEntry(normalizePath(entry))
-                : toEntry(normalizePath(entry))
+              toInput(entry, {
+                isProduction: isBuildTarget && configName === PRODUCTION_CONFIG_NAME,
+                maybeExternal: maybeExternal(option),
+              })
             );
           }
         }
       }
       for (const [option, entries] of defaultEntriesByOption.entries()) {
         for (const entry of entries) {
           inputs.add(
-            targetName === BUILD_TARGET_NAME && !productionEntriesByOption.get(option)?.length
-              ? toProductionEntry(normalizePath(entry))
-              : toEntry(normalizePath(entry))
+            toInput(entry, {
+              isProduction: isBuildTarget && !productionEntriesByOption.get(option)?.length,
+              maybeExternal: maybeExternal(option),
+            })
           );
         }
       }
@@ -109,6 +123,12 @@ const entriesByOption = (opts: TargetOptions): EntriesByOption =>
               typeof scriptStringOrObject === 'string' ? scriptStringOrObject : scriptStringOrObject.input
             )
           : [],
+      polyfills:
+        'polyfills' in opts && opts.polyfills
+          ? Array.isArray(opts.polyfills)
+            ? opts.polyfills
+            : [opts.polyfills]
+          : [],
       fileReplacements:
         'fileReplacements' in opts && opts.fileReplacements && Array.isArray(opts.fileReplacements)
           ? (opts.fileReplacements as FileReplacementsBuildOption).map(fileReplacement =>

packages/knip/test/plugins/angular.test.ts

@@ -22,7 +22,7 @@ test('Find dependencies with the Angular plugin', async () => {
     devDependencies: 1,
     unlisted: 1,
     unresolved: 1,
-    processed: 3,
-    total: 3,
+    processed: 4,
+    total: 4,
   });
 });

packages/knip/test/plugins/angular3.test.ts

@@ -18,8 +18,8 @@ test('Find dependencies with the Angular plugin (non-production)', async () => {
   assert.deepEqual(counters, {
     ...baseCounters,
     devDependencies: 1,
-    processed: 8,
-    total: 8,
+    processed: 10,
+    total: 10,
   });
 });
 
@@ -32,7 +32,7 @@ test('Find dependencies with the Angular plugin (production)', async () => {
 
   assert.deepEqual(counters, {
     ...baseCounters,
-    processed: 4,
-    total: 4,
+    processed: 5,
+    total: 5,
   });
 });