test: raise per-file coverage gate to 90 across all clients (closes #1271) (#1532)

* test(web): audit branch-coverage outliers, raise per-file gate to 70 (#1271)

The web per-file coverage gate had drifted red: the recently-landed EMA
auth feature (core/auth/ema/*) and ClientSettings components shipped
undertested, and the prior 50% branch floor let business-logic branches
go untested. CI does not run the coverage gate, so this accumulated.

Add tests to bring every failing file above the gate and push branch
coverage well past 70 across the board, then raise the per-file branches
threshold 50 -> 70 in clients/web/vite.config.ts.

- EMA core (emaFlow, resourceContext, jwt, wire): 50-88% -> 86-100% branch
- EMA OIDC/transport (idpOidc, tokenEndpoint, transportProvider): -> 97-100%
- oauthManager / discovery: 73-83% -> 88-92%
- ClientSettingsModal/Form, ConnectionInfoContent: 0-88% -> 96-100%
- useClientSettingsDraft / useEmaIdpLoginState hooks: 20% -> 100%
- TaskStatusBadge / SortableServerCard outliers: 50% -> 100%

Coverable branches reached by mocking useComputedColorScheme (dark theme),
dnd-kit useSortable (isDragging), and fetch/OIDC paths. Remaining sub-100
branches are genuinely-unreachable defensive guards or happy-dom-inherent
(portal / useMediaQuery / typeof window) and documented in test comments.

No source files changed. Global web branch coverage 88.73% -> 90.63%.
AGENTS.md updated; cli/tui/launcher stay at 50 (out of scope).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* test: raise per-file coverage gate to 90/90/90/90 across all clients

Follows the #1271 web branch-coverage audit (50 -> 70) by raising the
whole per-file gate to >=90 on all four dimensions — lines, statements,
functions, branches — for web, cli, tui, and launcher (core/ is measured
under the web suite). A codebase-wide audit added real tests for every
outlier and brought global coverage up across the board.

Config: all four vitest/vite coverage configs set to 90/90/90/90.
Two pure-type modules (core/mcp/import/types.ts, clients/web/server/
types.ts) added to the web coverage exclude list, matching the existing
type-only exclusions.

Tests: ~50 test files extended/created across core (auth, ema, mcp,
remote, state, storage, react), web components/screens/server, and the
cli/tui clients. Highlights: full EMA OAuth flow + transport coverage,
inspectorClient/remote server backfill, every Mantine control's handler
branches, and the cli unsupported-method / argv-fallback paths.

Genuinely-unreachable branches are annotated at the source with justified
`/* v8 ignore -- <reason> */` comments rather than lowering the gate:
happy-dom-inherent paths (Mantine portal, useMediaQuery, typeof window
SSR guards), React StrictMode effect replay, and provably-dead defensive
guards (?? fallbacks the types make impossible, Select.onChange values
outside the allowed list). No runtime logic changed; the only structural
edits are two behavior-preserving refactors (ResourceTemplatePanel hoists
the field value to a local so the ignore applies in JSX; ToolsScreen
swaps a ternary for an if) and prettier line-wrapping.

Also fixed a flaky real-timer debounce assertion in PromptArgumentsForm
(asserted an exact sibling-typing interleaving that raced the 300ms
debounce; now asserts the load-bearing fact — a non-empty fire-time
sibling capture).

AGENTS.md updated to describe the uniform 90 gate and the v8-ignore
policy. All four client coverage gates, root validate, storybook (370),
and smoke pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* test(web): make connect-crash SSE reader stop on the terminal event

`readSseEvents` looped until the server closed the stream (`done`). The
server closes the events stream immediately after writing the terminal
`transport_error`, but under the heavy parallel scheduler pressure of a
full `coverage` run (v8 instrumentation across all workers) that close
can lag far enough behind the event to trip the 30s test timeout — a
hang, not a wrong result. This made the test intermittently fail under
`npm run coverage` (it passed in isolation and under CI's lighter
`test:integration`).

Stop reading as soon as the terminal `transport_error` event arrives
(cancelling the reader) instead of waiting only for `done`. That event is
always the last one the session queue emits, so nothing is lost, and the
test no longer depends on stream-close timing. The `done` break is kept
for any stream that closes first.

Verified green across two consecutive full `npm run test:coverage` runs
(3094 tests) where it previously hung, plus isolation (~0.5s).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/web/src/test/integration/auth/node/oauth-callback-server.test.ts

@@ -1,9 +1,30 @@
 import { describe, it, expect, afterEach } from "vitest";
+import { connect } from "node:net";
 import {
   createOAuthCallbackServer,
   type OAuthCallbackServer,
 } from "@inspector/core/auth/node/oauth-callback-server.js";
 
+/**
+ * Send a raw HTTP request line over a socket so we can use request targets
+ * (like `//`) that `fetch` would normalize/reject before they reach the
+ * server. Returns the raw response text.
+ */
+function rawRequest(port: number, requestLine: string): Promise<string> {
+  return new Promise((resolve, reject) => {
+    const socket = connect(port, "127.0.0.1", () => {
+      socket.write(`${requestLine}\r\nHost: localhost\r\n\r\n`);
+    });
+    let data = "";
+    socket.setEncoding("utf8");
+    socket.on("data", (chunk) => {
+      data += chunk;
+    });
+    socket.on("end", () => resolve(data));
+    socket.on("error", reject);
+  });
+}
+
 describe("OAuthCallbackServer", () => {
   let server: OAuthCallbackServer;
 
@@ -219,6 +240,90 @@ describe("OAuthCallbackServer", () => {
     expect(first.status).toBe(200);
   });
 
+  it("returns 400 when the request target is an unparseable URL", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({ port: 0 });
+
+    // `GET //` makes req.url === "//", which `new URL("//", base)` rejects,
+    // exercising the try/catch 400 branch in handleRequest.
+    const raw = await rawRequest(result.port, "GET // HTTP/1.1");
+    expect(raw).toContain("400 Bad Request");
+    expect(raw).toContain("OAuth complete");
+  });
+
+  it("returns 400 JSON for an unparseable URL when Accept: application/json", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({ port: 0 });
+
+    const raw = await rawRequest(
+      result.port,
+      "GET // HTTP/1.1\r\nAccept: application/json",
+    );
+    expect(raw).toContain("400 Bad Request");
+    expect(raw).toContain('{"error":"Bad Request"}');
+  });
+
+  it("start() rejects when the callback path is not absolute", async () => {
+    server = createOAuthCallbackServer();
+    await expect(
+      server.start({ port: 0, path: "no-leading-slash" }),
+    ).rejects.toThrow(/Callback path must start with '\/'/);
+  });
+
+  it("POST returns 405 with a JSON body when Accept: application/json", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({ port: 0 });
+
+    const res = await fetch(
+      `http://localhost:${result.port}/oauth/callback?code=x`,
+      { method: "POST", headers: { Accept: "application/json" } },
+    );
+
+    expect(res.status).toBe(405);
+    expect(res.headers.get("content-type")).toContain("text/html");
+    expect(await res.json()).toEqual({ error: "Method Not Allowed" });
+  });
+
+  it("returns 404 with a JSON body when Accept: application/json", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({ port: 0 });
+
+    const res = await fetch(`http://localhost:${result.port}/nope`, {
+      headers: { Accept: "application/json" },
+    });
+
+    expect(res.status).toBe(404);
+    expect(await res.json()).toEqual({ error: "Not Found" });
+  });
+
+  it("returns 409 with a JSON body when Accept: application/json", async () => {
+    let release!: () => void;
+    const gate = new Promise<void>((resolve) => {
+      release = resolve;
+    });
+
+    server = createOAuthCallbackServer();
+    const result = await server.start({
+      port: 0,
+      onCallback: async () => {
+        await gate;
+      },
+    });
+
+    const firstP = fetch(
+      `http://localhost:${result.port}/oauth/callback?code=first`,
+    );
+    await new Promise((r) => setTimeout(r, 50));
+    const second = await fetch(
+      `http://localhost:${result.port}/oauth/callback?code=second`,
+      { headers: { Accept: "application/json" } },
+    );
+    expect(second.status).toBe(409);
+    expect(await second.json()).toEqual({ error: "Callback already handled" });
+    release();
+    await firstP;
+  });
+
   it("onCallback rejection returns 500 and error HTML", async () => {
     server = createOAuthCallbackServer();
     const result = await server.start({
@@ -237,4 +342,51 @@ describe("OAuthCallbackServer", () => {
     expect(html).toContain("OAuth failed");
     expect(html).toContain("exchange failed");
   });
+
+  it("onCallback rejection with a non-Error stringifies the value (500)", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({
+      port: 0,
+      onCallback: async () => {
+        throw "string-failure";
+      },
+    });
+
+    const res = await fetch(
+      `http://localhost:${result.port}/oauth/callback?code=abc`,
+    );
+
+    expect(res.status).toBe(500);
+    expect(await res.text()).toContain("string-failure");
+  });
+
+  it("GET with error but no error_description still returns 400 and calls onError", async () => {
+    server = createOAuthCallbackServer();
+    const errors: Array<{
+      error: string;
+      error_description?: string | null;
+    }> = [];
+    const result = await server.start({
+      port: 0,
+      onError: (p) => errors.push(p),
+    });
+
+    const res = await fetch(
+      `http://localhost:${result.port}/oauth/callback?error=invalid_request`,
+    );
+
+    expect(res.status).toBe(400);
+    expect(errors).toHaveLength(1);
+    expect(errors[0]!.error).toBe("invalid_request");
+    expect(errors[0]!.error_description).toBeUndefined();
+  });
+
+  it("builds a bracketed redirect URL for an IPv6 hostname", async () => {
+    server = createOAuthCallbackServer();
+    const result = await server.start({ port: 0, hostname: "::1" });
+
+    expect(result.redirectUrl).toBe(
+      `http://[::1]:${result.port}/oauth/callback`,
+    );
+  });
 });

clients/web/src/test/integration/auth/node/secret-store.test.ts

@@ -311,6 +311,13 @@ describe("KeyringSecretStore (mocked native bindings)", () => {
     ).toBe("p");
   });
 
+  it("KeychainUnavailableError stringifies a non-Error cause", () => {
+    const err = new KeychainUnavailableError("plain string cause");
+    expect(err).toBeInstanceOf(KeychainUnavailableError);
+    expect(err.message).toContain("plain string cause");
+    expect(err.message).toMatch(/libsecret/);
+  });
+
   it("KeychainUnavailableError carries the underlying error message", async () => {
     keyringMocks.failures.setThrows = true;
     try {

clients/web/src/test/integration/auth/node/storage.test.ts

@@ -1,4 +1,4 @@
-import { describe, it, expect, beforeEach, afterEach } from "vitest";
+import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
 import {
   NodeOAuthStorage,
   getOAuthStore,
@@ -590,6 +590,22 @@ describe("NodeOAuthStorage with custom storagePath", () => {
     expect(all.getServerState("http://server-b.test").tokens).toBeUndefined();
   });
 
+  it("clearAllOAuthClientState tolerates a store whose servers map is absent", () => {
+    // Exercises the `state.servers ?? {}` nullish fallback: when the persisted
+    // state lacks a `servers` map, the iteration must default to {} (no throw).
+    const defaultStore = getOAuthStore();
+    const clearServerState = vi.fn();
+    vi.spyOn(defaultStore, "getState").mockReturnValue({
+      servers: undefined,
+      clearServerState,
+    } as unknown as ReturnType<typeof defaultStore.getState>);
+
+    expect(() => clearAllOAuthClientState()).not.toThrow();
+    expect(clearServerState).not.toHaveBeenCalled();
+
+    vi.mocked(defaultStore.getState).mockRestore();
+  });
+
   it("should isolate state from default store", async () => {
     const customPath = path.join(
       os.tmpdir(),