Don't unconditonally use a path mapping

Author: Andy Hanson

src/compiler/moduleSpecifiers.ts

@@ -87,11 +87,9 @@ namespace ts.moduleSpecifiers {
     function getLocalModuleSpecifiers(
         moduleFileName: string,
         { moduleResolutionKind, addJsExtension, getCanonicalFileName, sourceDirectory }: Info,
-        compilerOptions: CompilerOptions,
+        { baseUrl, paths, rootDirs }: CompilerOptions,
         preferences: ModuleSpecifierPreferences,
     ): ReadonlyArray<string> {
-        const { baseUrl, paths, rootDirs } = compilerOptions;
-
         const relativePath = rootDirs && tryGetModuleNameFromRootDirs(rootDirs, moduleFileName, sourceDirectory, getCanonicalFileName) ||
             removeExtensionAndIndexPostFix(ensurePathIsNonModuleName(getRelativePathFromDirectory(sourceDirectory, moduleFileName, getCanonicalFileName)), moduleResolutionKind, addJsExtension);
         if (!baseUrl || preferences.importModuleSpecifierPreference === "relative") {
@@ -113,7 +111,7 @@ namespace ts.moduleSpecifiers {
 
         if (preferences.importModuleSpecifierPreference !== undefined) Debug.assertNever(preferences.importModuleSpecifierPreference);
 
-        if (isPathRelativeToParent(relativeToBaseUrl)) {
+        if (isPathRelativeToParent(nonRelative)) {
             return [relativePath];
         }
 

tests/cases/fourslash/importNameCodeFixNewImportPaths0.ts

@@ -18,5 +18,8 @@
 verify.importFixAtPosition([
 `import { foo } from "a";
 
-foo();`
+foo();`,
+`import { foo } from "./folder_a/f2";
+
+foo();`,
 ]);

tests/cases/fourslash/importNameCodeFixNewImportPaths1.ts

@@ -18,5 +18,8 @@
 verify.importFixAtPosition([
 `import { foo } from "b/f2";
 
-foo();`
+foo();`,
+`import { foo } from "./folder_b/f2";
+
+foo();`,
 ]);

tests/cases/fourslash/importNameCodeFixNewImportPaths2.ts

@@ -24,5 +24,8 @@
 verify.importFixAtPosition([
 `import { foo } from "b";
 
-foo();`
+foo();`,
+`import { foo } from "./folder_b";
+
+foo();`,
 ]);

tests/cases/fourslash/importNameCodeFixNewImportPaths_preferRelative.ts

@@ -0,0 +1,27 @@
+/// <reference path="fourslash.ts" />
+
+// @Filename: /tsconfig.json
+////{
+////    "compilerOptions": {
+////        "baseUrl": ".",
+////        "paths": {
+////            "mapped/*": ["mapped/*"]
+////        }
+////    }
+////}
+
+// @Filename: /mapped/a.ts
+////foo;
+
+// @Filename: /mapped/b.ts
+////export const foo = 0;
+
+goTo.file("/mapped/a.ts");
+verify.importFixAtPosition([
+`import { foo } from "./b";
+
+foo;`,
+`import { foo } from "mapped/b";
+
+foo;`,
+]);

tests/cases/fourslash/importNameCodeFixNewImportPaths_withExtension.ts

@@ -19,5 +19,8 @@
 verify.importFixAtPosition([
 `import { foo } from "foo";
 
-foo`
+foo`,
+`import { foo } from "./thisHasPathMapping";
+
+foo`,
 ]);

tests/cases/fourslash/importNameCodeFixNewImportPaths_withLeadingDotSlash.ts

@@ -19,5 +19,8 @@
 verify.importFixAtPosition([
 `import { foo } from "foo";
 
-foo`
+foo`,
+`import { foo } from "./thisHasPathMapping";
+
+foo`,
 ]);

tests/cases/fourslash/importNameCodeFixNewImportPaths_withParentRelativePath.ts

@@ -19,5 +19,8 @@
 verify.importFixAtPosition([
 `import { foo } from "foo";
 
-foo`
+foo`,
+`import { foo } from "../thisHasPathMapping";
+
+foo`,
 ]);

tests/cases/fourslash/importNameCodeFix_fromPathMapping.ts

@@ -20,5 +20,8 @@ goTo.file("/b.ts");
 verify.importFixAtPosition([
 `import { foo } from "@root/a";
 
+foo;`,
+`import { foo } from "./a";
+
 foo;`,
 ]);