When adding relative completions with rootDirs, still add completions for regular relative imports (#28561)

Author: Andy

Diff for: src/services/stringCompletions.ts

@@ -281,33 +281,26 @@ namespace ts.Completions.StringCompletions {
      * Takes a script path and returns paths for all potential folders that could be merged with its
      * containing folder via the "rootDirs" compiler option
      */
-    function getBaseDirectoriesFromRootDirs(rootDirs: string[], basePath: string, scriptPath: string, ignoreCase: boolean): string[] {
+    function getBaseDirectoriesFromRootDirs(rootDirs: string[], basePath: string, scriptDirectory: string, ignoreCase: boolean): ReadonlyArray<string> {
         // Make all paths absolute/normalized if they are not already
         rootDirs = rootDirs.map(rootDirectory => normalizePath(isRootedDiskPath(rootDirectory) ? rootDirectory : combinePaths(basePath, rootDirectory)));
 
         // Determine the path to the directory containing the script relative to the root directory it is contained within
         const relativeDirectory = firstDefined(rootDirs, rootDirectory =>
-            containsPath(rootDirectory, scriptPath, basePath, ignoreCase) ? scriptPath.substr(rootDirectory.length) : undefined)!; // TODO: GH#18217
+            containsPath(rootDirectory, scriptDirectory, basePath, ignoreCase) ? scriptDirectory.substr(rootDirectory.length) : undefined)!; // TODO: GH#18217
 
         // Now find a path for each potential directory that is to be merged with the one containing the script
         return deduplicate<string>(
-            rootDirs.map(rootDirectory => combinePaths(rootDirectory, relativeDirectory)),
+            [...rootDirs.map(rootDirectory => combinePaths(rootDirectory, relativeDirectory)), scriptDirectory],
             equateStringsCaseSensitive,
             compareStringsCaseSensitive);
     }
 
-    function getCompletionEntriesForDirectoryFragmentWithRootDirs(rootDirs: string[], fragment: string, scriptPath: string, extensionOptions: ExtensionOptions, compilerOptions: CompilerOptions, host: LanguageServiceHost, exclude?: string): NameAndKind[] {
+    function getCompletionEntriesForDirectoryFragmentWithRootDirs(rootDirs: string[], fragment: string, scriptDirectory: string, extensionOptions: ExtensionOptions, compilerOptions: CompilerOptions, host: LanguageServiceHost, exclude: string): ReadonlyArray<NameAndKind> {
         const basePath = compilerOptions.project || host.getCurrentDirectory();
         const ignoreCase = !(host.useCaseSensitiveFileNames && host.useCaseSensitiveFileNames());
-        const baseDirectories = getBaseDirectoriesFromRootDirs(rootDirs, basePath, scriptPath, ignoreCase);
-
-        const result: NameAndKind[] = [];
-
-        for (const baseDirectory of baseDirectories) {
-            getCompletionEntriesForDirectoryFragment(fragment, baseDirectory, extensionOptions, host, exclude, result);
-        }
-
-        return result;
+        const baseDirectories = getBaseDirectoriesFromRootDirs(rootDirs, basePath, scriptDirectory, ignoreCase);
+        return flatMap(baseDirectories, baseDirectory => getCompletionEntriesForDirectoryFragment(fragment, baseDirectory, extensionOptions, host, exclude));
     }
 
     /**

Diff for: tests/cases/fourslash/completionForStringLiteralRelativeImport4.ts

@@ -2,23 +2,29 @@
 
 // Should give completions for directories that are merged via the rootDirs compiler option
 
-// @rootDirs: tests/cases/fourslash/sub/src1,tests/cases/fourslash/src2
+// @rootDirs: /sub/src1,/src2
 
-// @Filename: src2/test0.ts
+// @Filename: /src2/test0.ts
 //// import * as foo1 from "./mo/*import_as0*/
 //// import foo2 = require("./mo/*import_equals0*/
 //// var foo3 = require("./mo/*require0*/
 
-// @Filename: src2/module0.ts
+// @Filename: /src2/inner/inner0.ts
+////import * as s from ".//*inner*/";
+
+// @Filename: /src2/inner/inner1.ts
+////export const x = 0;
+
+// @Filename: /src2/module0.ts
 //// export var w = 0;
 
-// @Filename: sub/src1/module1.ts
+// @Filename: /sub/src1/module1.ts
 //// export var x = 0;
 
-// @Filename: sub/src1/module2.ts
+// @Filename: /sub/src1/module2.ts
 //// export var y = 0;
 
-// @Filename: sub/src1/more/module3.ts
+// @Filename: /sub/src1/more/module3.ts
 //// export var z = 0;
 
 
@@ -37,8 +43,15 @@
 // @Filename: e2.js
 ////
 
-verify.completions({
-    marker: test.markers(),
-    exact: ["module1", "module2", "more", "module0"],
-    isNewIdentifierLocation: true,
-});
+verify.completions(
+    {
+        marker: ["import_as0", "import_equals0", "require0"],
+        exact: ["module1", "module2", "more", "module0", "inner"],
+        isNewIdentifierLocation: true,
+    },
+    {
+        marker: "inner",
+        exact: "inner1",
+        isNewIdentifierLocation: true,
+    }
+);