feat(search): list directories in Go to File and Search Everywhere

Go to File and the Files section of Search Everywhere listed only files, so a
folder could not be found by name. Directories from the index's folder search
now rank with the files (a file first on equal scores), with a folder icon, and
choosing one selects it in the Project view. A file type filter or a
File.kt:42 query still lists files only.

src/features/search/__tests__/controller.test.ts

@@ -83,6 +83,44 @@ describe("SeController", () => {
     expect(deps.cancel).toHaveBeenCalled();
   });
 
+  it("lists directories with the files, by score, files first on a tie", async () => {
+    const { c, last } = setup({
+      findFiles: async () => [
+        { ...fm("src/util.ts"), score: 5 },
+        { ...fm("lib/utils/a.ts"), score: 2 },
+      ],
+      findDirs: async () => [
+        { path: "/p/src/utils", relPath: "src/utils/", score: 5, indices: [4, 5, 6, 7] },
+        { path: "/p/lib/utils", relPath: "lib/utils/", score: 3, indices: [] },
+      ],
+    });
+    c.run({ query: "util", tab: "files", includeNonProject: false, extra: {} });
+    await flush();
+    const items = last().sections.get("files")!.items;
+    expect(items.map((i) => i.key)).toEqual([
+      "f:/p/src/util.ts",
+      "d:/p/src/utils",
+      "d:/p/lib/utils",
+      "f:/p/lib/utils/a.ts",
+    ]);
+    expect(items[1]).toMatchObject({
+      kind: "file",
+      folder: true,
+      name: "utils",
+      dir: "src",
+      nameIndices: [0, 1, 2, 3],
+    });
+
+    // A `File.kt:42` query asks for a file.
+    c.run({ query: "util:3", tab: "files", includeNonProject: false, extra: {} });
+    await flush();
+    expect(
+      last()
+        .sections.get("files")!
+        .items.every((i) => !("folder" in i) || !i.folder),
+    ).toBe(true);
+  });
+
   it("parses File.kt:42 and opens files at the line", async () => {
     const findFiles = vi.fn(async () => [fm("File.kt")]);
     const { c, last } = setup({ findFiles });

src/features/search/everywhere/SearchEverywhere.tsx

@@ -313,6 +313,8 @@ function SearchEverywhereDialog() {
         return;
       }
       case "file":
+        if (row.folder) return closeThen(() => void executeAction("navigate.selectInProjectView", row.path));
+        return closeThen(() => void openResult(row, { side }));
       case "symbol":
       case "text":
         return closeThen(() => void openResult(row, { side }));
@@ -448,7 +450,8 @@ function SearchEverywhereDialog() {
   useEffect(() => {
     if (nothingInProject) widenSearchEverywhere(searchQuery);
   }, [nothingInProject, searchQuery]);
-  const canSplit = activeRow?.kind === "file" || activeRow?.kind === "symbol" || activeRow?.kind === "text";
+  const canSplit =
+    (activeRow?.kind === "file" && !activeRow.folder) || activeRow?.kind === "symbol" || activeRow?.kind === "text";
   const onTabKey = (e: KeyboardEvent<HTMLDivElement>) => {
     if (e.key !== "ArrowRight" && e.key !== "ArrowLeft") return;
     e.preventDefault();
@@ -708,7 +711,7 @@ function describe(row: SeRow | undefined): string {
 function previewOf(row: SeRow | undefined): { path: string; line: number; highlights: PreviewHighlight[] } | null {
   switch (row?.kind) {
     case "file":
-      return { path: row.path, line: row.line ?? 0, highlights: [] };
+      return row.folder ? null : { path: row.path, line: row.line ?? 0, highlights: [] };
     case "symbol":
       return {
         path: row.path,
@@ -780,7 +783,16 @@ function ResultRow({
         </span>
       );
     case "file":
-      return <FileRow path={row.path} name={row.name} dir={row.dir} indices={row.nameIndices} line={row.line} />;
+      return (
+        <FileRow
+          path={row.path}
+          name={row.name}
+          dir={row.dir}
+          indices={row.nameIndices}
+          line={row.line}
+          folder={row.folder}
+        />
+      );
     case "symbol":
       return (
         <>
@@ -911,18 +923,20 @@ function FileRow({
   dir,
   indices,
   line,
+  folder,
 }: {
   path: string;
   name: string;
   dir: string;
   indices: number[];
   line: number | null;
+  folder?: boolean;
 }) {
   const deco = useFileDecoration(path);
   const { icon } = useFilePresentation(path);
   return (
     <>
-      <Icon name={icon} size={16} className={styles.icon} />
+      <Icon name={folder ? "folder" : icon} size={16} className={styles.icon} />
       <span className={styles.main}>
         <span className={styles.name} style={deco.color ? { color: deco.color } : undefined}>
           <HighlightedText text={name} indices={indices} tone="strong" />
@@ -935,8 +949,9 @@ function FileRow({
 }
 
 type NavigationRow = Extract<SeRow, { kind: "file" | "symbol" | "text" }>;
+/** A row that opens in an editor (a directory selects in the Project view instead). */
 function isNavigationRow(row: SeRow): row is NavigationRow {
-  return row.kind === "file" || row.kind === "symbol" || row.kind === "text";
+  return (row.kind === "file" && !row.folder) || row.kind === "symbol" || row.kind === "text";
 }
 function openResult(row: NavigationRow, options: Parameters<typeof openLocation>[2]): Promise<void> {
   if (row.kind === "file")

src/features/search/everywhere/controller.ts

@@ -26,6 +26,7 @@ import {
   TAB_LIMIT,
   actionItem,
   fileItem,
+  folderItem,
   matchActions,
   matchSettings,
   mergeActionResults,
@@ -40,6 +41,8 @@ import {
 
 export interface SeDeps {
   findFiles(query: string, limit: number): Promise<FileMatch[]>;
+  /** Directories by name or path (`relPath` ending in `/`), listed with the files. */
+  findDirs?(query: string, limit: number): Promise<FileMatch[]>;
   findSymbols(query: string, filter: SymbolFilter, limit: number): Promise<SymbolMatch[]>;
   /** Optional language-server symbols; rejects with `unavailable` when no server. */
   workspaceSymbols?(request: RequestId, query: string): Promise<WorkspaceSymbol[]>;
@@ -253,12 +256,24 @@ export class SeController {
               ? (path: string) => (!scope || scope(path)) && (!filter || passesFilter(filter, path))
               : null;
           // Over-fetch so a narrowed scope still fills the section.
-          const fetched = await this.deps.findFiles(text, keep ? limit * 4 + 1 : limit + 1);
-          const matches = keep ? fetched.filter((m) => keep(m.path)) : fetched;
+          const want = keep ? limit * 4 + 1 : limit + 1;
+          // Directories rank with the files (equal scores: the file first); a file type filter
+          // and a `File.kt:42` query ask for files only.
+          const withDirs = !!this.deps.findDirs && !!text && !filter && q.line === null;
+          const [fetched, dirs] = await Promise.all([
+            this.deps.findFiles(text, want),
+            withDirs ? this.deps.findDirs!(text, want).catch(() => []) : [],
+          ]);
+          const merged = dirs.length
+            ? [...fetched.map((m) => ({ m, folder: false })), ...dirs.map((m) => ({ m, folder: true }))].sort(
+                (a, b) => b.m.score - a.m.score || Number(a.folder) - Number(b.folder),
+              )
+            : fetched.map((m) => ({ m, folder: false }));
+          const matches = keep ? merged.filter(({ m }) => keep(m.path)) : merged;
           this.set(
             id,
             gen,
-            matches.slice(0, limit).map((m) => fileItem(m, q.line, q.col)),
+            matches.slice(0, limit).map(({ m, folder }) => (folder ? folderItem(m) : fileItem(m, q.line, q.col))),
             matches.length > limit,
             false,
           );

src/features/search/everywhere/deps.ts

@@ -12,6 +12,7 @@ import { recentActions } from "./store";
 export function ipcDeps(ctx: ContextKeys): SeDeps {
   return {
     findFiles: (q, limit) => call(commands.findFiles(q, limit)),
+    findDirs: (q, limit) => call(commands.findDirs(q, limit)),
     findSymbols: (q, filter, limit) => call(commands.findSymbols(q, filter, limit)),
     workspaceSymbols: (request, q) => call(commands.lspWorkspaceSymbols(request, q)),
     searchText: async (request, query, onFile) => {

src/features/search/everywhere/model.ts

@@ -76,6 +76,8 @@ export interface FileItem {
   nameIndices: number[];
   line: number | null;
   col: number | null;
+  /** A directory: choosing it selects it in the Project view. */
+  folder?: boolean;
 }
 
 export interface SymbolItem {
@@ -169,6 +171,12 @@ export function fileItem(
   };
 }
 
+/** A directory match (`relPath` ends in `/`), listed with the files as IDEA's Go to File does. */
+export function folderItem(m: Pick<FileMatch, "path" | "relPath" | "indices">): FileItem {
+  const rel = m.relPath.replace(/\/$/, "");
+  return { ...fileItem({ ...m, relPath: rel }), key: `d:${m.path}`, folder: true };
+}
+
 export function symbolItem(m: SymbolMatch): SymbolItem {
   return {
     kind: "symbol",