feat(usages): search Java usages in Project Files first, Project and Libraries on demand (#1837)

src/features/code-insight/usageResults.test.ts

@@ -5,12 +5,33 @@ vi.mock("@/workbench/contributions", async (orig) => ({
   ...(await orig<typeof import("@/workbench/contributions")>()),
   toolWindowService: () => ({ show }),
 }));
+const referenceResponse = vi.fn();
+const lspReferences = vi.fn(async (..._args: unknown[]) => ({ status: "ok", data: null }));
+vi.mock("@/platform/ipc", async (orig) => {
+  const actual = await orig<typeof import("@/platform/ipc")>();
+  return { ...actual, commands: { ...actual.commands, lspReferences } };
+});
 vi.mock("./ipc", async (orig) => ({
   ...(await orig<typeof import("./ipc")>()),
-  readManyFileLines: async () => new Map([["/p/b.rs", ["", "    used();"]]]),
+  caretContext: () => ({ doc: 1, path: "/p/a.rs", line: 0, col: 0, word: "used", view: null }),
+  lspRequest: (request: () => unknown) => {
+    request();
+    return referenceResponse();
+  },
+  readManyFileLines: async () => new Map([["/p/b.rs", ["", "    used();", "    used();"]]]),
+}));
+const channels: { onmessage: (refs: unknown) => void }[] = [];
+vi.mock("@tauri-apps/api/core", async (orig) => ({
+  ...(await orig<object>()),
+  Channel: class {
+    onmessage = () => {};
+    constructor() {
+      channels.push(this);
+    }
+  },
 }));
 
-const { activeUsageSearch, openUsageTab, pinUsageTab, resetUsages, showUsageResults, useUsages } =
+const { activeUsageSearch, findUsages, openUsageTab, pinUsageTab, resetUsages, showUsageResults, useUsages } =
   await import("./usages");
 
 describe("showUsageResults", () => {
@@ -25,6 +46,19 @@ describe("showUsageResults", () => {
     ]);
   });
 
+  it("shows the lines the server gave along for files it does not read", async () => {
+    const lib = {
+      path: "jdt://contents/lib/Lib.class",
+      range: { start: { line: 3, col: 4 }, end: { line: 3, col: 8 } },
+    };
+    await showUsageResults({
+      symbol: "used",
+      locations: [lib],
+      classified: [{ location: lib, kind: "unknown", text: "    used();" }],
+    });
+    expect(activeUsageSearch(useUsages.getState())!.groups[0]!.usages[0]!.text).toBe("    used();");
+  });
+
   it("ignores malformed arguments", async () => {
     show.mockClear();
     await showUsageResults({ symbol: "x" });
@@ -32,6 +66,47 @@ describe("showUsageResults", () => {
   });
 });
 
+describe("findUsages", () => {
+  it("searches Project Files, then Project and Libraries on request", async () => {
+    const at = { path: "/p/b.rs", range: { start: { line: 1, col: 4 }, end: { line: 1, col: 8 } } };
+    lspReferences.mockClear();
+    referenceResponse.mockResolvedValueOnce({ locations: [at], incomplete: null, librariesSkipped: true });
+    await findUsages();
+    const project = activeUsageSearch(useUsages.getState())!;
+    expect(project).toMatchObject({ loading: false, scope: "project" });
+    expect(lspReferences.mock.lastCall![5]).toBe(false);
+    referenceResponse.mockResolvedValueOnce({ locations: [at], incomplete: null });
+    project.searchLibraries!();
+    await vi.waitFor(() => expect(activeUsageSearch(useUsages.getState())!.loading).toBe(false));
+    expect(lspReferences.mock.lastCall![5]).toBe(true);
+    const all = activeUsageSearch(useUsages.getState())!;
+    expect(all.scope).toBe("libraries");
+    // Rerun keeps the scope.
+    referenceResponse.mockResolvedValueOnce({ locations: [at], incomplete: null });
+    all.rerun!();
+    await vi.waitFor(() => expect(lspReferences).toHaveBeenCalledTimes(3));
+    expect(lspReferences.mock.lastCall![5]).toBe(true);
+    resetUsages();
+  });
+
+  it("shows the usages found first while it searches for the rest", async () => {
+    const at = (line: number) => ({ path: "/p/b.rs", range: { start: { line, col: 4 }, end: { line, col: 8 } } });
+    let resolve!: (refs: unknown) => void;
+    referenceResponse.mockReturnValueOnce(new Promise((r) => (resolve = r)));
+    const search = findUsages();
+    await vi.waitFor(() => expect(channels).not.toHaveLength(0));
+    channels.at(-1)!.onmessage({ locations: [at(1)], incomplete: null });
+    await vi.waitFor(() => expect(activeUsageSearch(useUsages.getState())!.groups).toHaveLength(1));
+    expect(activeUsageSearch(useUsages.getState())).toMatchObject({ loading: true, error: null });
+    resolve({ locations: [at(1), at(2)], incomplete: null });
+    await search;
+    const done = activeUsageSearch(useUsages.getState())!;
+    expect(done.loading).toBe(false);
+    expect(done.groups[0]!.usages.map((u) => u.line)).toEqual([1, 2]);
+    resetUsages();
+  });
+});
+
 describe("usage tabs", () => {
   const search = (id: number) => ({
     id,