Make TS-style path mappings work for all files with extensions (#673)

webpro-nl · Jun 13, 2024 · e9b3e66 · e9b3e66
1 parent 8697dbe
commit e9b3e66
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Showing 5 changed files with 62 additions and 32 deletions.
diff --git a/bun.lockb b/bun.lockb
diff --git a/packages/knip/fixtures/paths/index.ts b/packages/knip/fixtures/paths/index.ts
@@ -1,7 +1,9 @@
 import index from '@lib';
 import fn from '@lib/fn';
+import customExt from '@lib/data.ext';
 import js from 'xyz/main.js';
 import anything from '~/my-module';
+customExt;
 index;
 fn;
 js;

diff --git a/packages/knip/fixtures/paths/lib/data.ext b/packages/knip/fixtures/paths/lib/data.ext
diff --git a/packages/knip/package.json b/packages/knip/package.json
@@ -72,6 +72,7 @@
     "smol-toml": "^1.1.4",
     "strip-json-comments": "5.0.1",
     "summary": "2.1.0",
+    "tsconfig-paths": "^4.2.0",
     "zod": "^3.22.4",
     "zod-validation-error": "^3.0.3"
   },

diff --git a/packages/knip/src/typescript/resolveModuleNames.ts b/packages/knip/src/typescript/resolveModuleNames.ts
@@ -1,5 +1,6 @@
 import { existsSync } from 'node:fs';
 import { isBuiltin } from 'node:module';
+import { createMatchPath } from 'tsconfig-paths';
 import ts from 'typescript';
 import { DEFAULT_EXTENSIONS, FOREIGN_FILE_EXTENSIONS } from '../constants.js';
 import { timerify } from '../util/Performance.js';
@@ -54,6 +55,13 @@ export function createCustomModuleResolver(
     });
   }
 
+  const tsMatchPath = createMatchPath(
+    // If `baseUrl` is undefined we have already modified `paths` so that all
+    // entries are absolute. See `mergePaths` in `src/PrincipalFactory.ts`.
+    compilerOptions.baseUrl ?? '/',
+    compilerOptions.paths || {}
+  );
+
   /**
    * - Virtual files have built-in or custom compiler, return as JS
    * - Foreign files have path resolved verbatim (file manager will return empty source file)
@@ -65,30 +73,28 @@ export function createCustomModuleResolver(
     // No need to try and resolve builtins or externals, bail out
     if (isBuiltin(sanitizedSpecifier) || isInNodeModules(name)) return undefined;
 
-    {
-      const resolvedFileName = resolveSync(sanitizedSpecifier, containingFile, extensions);
-      if (resolvedFileName) {
-        const ext = extname(resolvedFileName);
-
-        if (!virtualFileExtensions.includes(ext) && !FOREIGN_FILE_EXTENSIONS.has(ext)) {
-          const srcFilePath = toSourceFilePath(resolvedFileName);
-          if (srcFilePath) {
-            return {
-              resolvedFileName: srcFilePath,
-              extension: extname(srcFilePath),
-              isExternalLibraryImport: false,
-              resolvedUsingTsExtension: false,
-            };
-          }
-        }
+    const resolvedFileName = resolveSync(sanitizedSpecifier, containingFile, extensions);
+    if (resolvedFileName) {
+      const ext = extname(resolvedFileName);
 
-        return {
-          resolvedFileName,
-          extension: virtualFileExtensions.includes(ext) ? ts.Extension.Js : ext,
-          isExternalLibraryImport: isInNodeModules(resolvedFileName),
-          resolvedUsingTsExtension: false,
-        };
+      if (!virtualFileExtensions.includes(ext) && !FOREIGN_FILE_EXTENSIONS.has(ext)) {
+        const srcFilePath = toSourceFilePath(resolvedFileName);
+        if (srcFilePath) {
+          return {
+            resolvedFileName: srcFilePath,
+            extension: extname(srcFilePath),
+            isExternalLibraryImport: false,
+            resolvedUsingTsExtension: false,
+          };
+        }
       }
+
+      return {
+        resolvedFileName,
+        extension: virtualFileExtensions.includes(ext) ? ts.Extension.Js : ext,
+        isExternalLibraryImport: isInNodeModules(resolvedFileName),
+        resolvedUsingTsExtension: false,
+      };
     }
 
     const tsResolvedModule = ts.resolveModuleName(
@@ -122,21 +128,42 @@ export function createCustomModuleResolver(
       customSys
     ).resolvedModule;
 
-    if (!customResolvedModule || !isVirtualFilePath(customResolvedModule.resolvedFileName, virtualFileExtensions)) {
-      const module = fileExists(sanitizedSpecifier, containingFile);
-      if (module) return module;
+    if (customResolvedModule) {
+      if (isVirtualFilePath(customResolvedModule.resolvedFileName, virtualFileExtensions)) {
+        const resolvedFileName = ensureRealFilePath(customResolvedModule.resolvedFileName, virtualFileExtensions);
+
+        return {
+          extension: ts.Extension.Js,
+          resolvedFileName,
+          isExternalLibraryImport: customResolvedModule.isExternalLibraryImport,
+        };
+      }
+
       return customResolvedModule;
     }
 
-    const resolvedFileName = ensureRealFilePath(customResolvedModule.resolvedFileName, virtualFileExtensions);
+    const module = fileExists(sanitizedSpecifier, containingFile);
+    if (module) return module;
 
-    const resolvedModule: ts.ResolvedModuleFull = {
-      extension: ts.Extension.Js,
-      resolvedFileName,
-      isExternalLibraryImport: customResolvedModule.isExternalLibraryImport,
-    };
+    const resolvedPathMap = tsMatchPath(
+      sanitizedSpecifier,
+      undefined,
+      undefined,
+      // Leave extensions empty. When resolving "@foo/bar.ext",
+      // "@foo/bar.ext.js" will not be tried if "./foo/bar.ext" does not exist.
+      // This case has been handled by the resolvers above. This makes the
+      // resolution faster.
+      []
+    );
+    if (resolvedPathMap) {
+      return {
+        resolvedFileName: resolvedPathMap,
+        extension: extname(resolvedPathMap),
+        isExternalLibraryImport: false,
+      };
+    }
 
-    return resolvedModule;
+    return undefined;
   }
 
   return timerify(resolveModuleNames);