fix(guided-review): load the review list when glab is not installed

plugins/guided-review/server/forge/cli.ts

@@ -26,6 +26,11 @@ type FileCall = CallOptions & { maxBytes: number };
 /** Long enough for a paginated file list on a large PR, short enough that a hung call ends. */
 export const DEFAULT_CLI_TIMEOUT_MS = 120_000;
 
+/** The CLI is not where the settings say, which for a reviewer on only the other forge means it is not installed. */
+export class CliNotFoundError extends ForgeError {
+  override name = "CliNotFoundError";
+}
+
 /** One forge CLI, whose failures come back as a `ForgeError` in a sentence. */
 export type Cli = {
   text(args: readonly string[], options?: CallOptions): Promise<string>;
@@ -61,9 +66,8 @@ export function createCli(options: CliOptions): Cli {
     }
     if (result.spawnError !== null) {
       if (/ENOENT|EACCES/.test(result.spawnError)) {
-        throw new ForgeError(
-          `Could not run ${options.name} at "${binary}" (${result.spawnError}). Set the ${options.name} path in the Guided Review settings.`,
-        );
+        const message = `Could not run ${options.name} at "${binary}" (${result.spawnError}). Set the ${options.name} path in the Guided Review settings.`;
+        throw /ENOENT/.test(result.spawnError) ? new CliNotFoundError(message) : new ForgeError(message);
       }
       throw new ForgeError(`${options.name} did not finish: ${result.spawnError}.`);
     }

plugins/guided-review/server/forge/github.test.ts

@@ -3,6 +3,7 @@ import { readFileSync } from "node:fs";
 import path from "node:path";
 import test from "node:test";
 import { fakeCommandRunner, type FakeCommandRunner, type ScriptedResult } from "../fake-command-runner.ts";
+import { CliNotFoundError } from "./cli.ts";
 import {
   ADD_THREAD_MUTATION,
   AUTHORED_SEARCH_QUERY,
@@ -182,7 +183,7 @@ test("a gh that cannot run points at the setting", async () => {
 
   await assert.rejects(
     forge.fetchChangeRequest(PR_105),
-    new ForgeError(
+    new CliNotFoundError(
       'Could not run gh at "/opt/gh/bin/gh" (spawn /opt/gh/bin/gh ENOENT). Set the gh path in the Guided Review settings.',
     ),
   );

plugins/guided-review/server/forge/gitlab.test.ts

@@ -5,6 +5,7 @@ import test from "node:test";
 import type { LineRef } from "../../shared/drafts.ts";
 import { anchorAt } from "../anchors.ts";
 import { fakeCommandRunner, type ScriptedResult } from "../fake-command-runner.ts";
+import { CliNotFoundError } from "./cli.ts";
 import { createGitLabForge, parseAuthStatus, parseMergeRequestUrl, REQUEST_CHANGES_MUTATION, REVIEW_LIST_QUERY, uploadOf } from "./gitlab.ts";
 import { ForgeError, type AnchorLine, type ChangeRequestRef, type DraftAnchor, type DraftTarget } from "./port.ts";
 
@@ -290,7 +291,7 @@ test("a glab that cannot run points at the setting", async () => {
 
   await assert.rejects(
     forge.matchUrl(MR_3931.url),
-    new ForgeError('Could not run glab at "/usr/bin/glab" (spawn /usr/bin/glab ENOENT). Set the glab path in the Guided Review settings.'),
+    new CliNotFoundError('Could not run glab at "/usr/bin/glab" (spawn /usr/bin/glab ENOENT). Set the glab path in the Guided Review settings.'),
   );
 });
 
@@ -1219,6 +1220,12 @@ test("lists the open MRs the viewer reviews on each host glab is logged in to, a
   });
 });
 
+test("lists no host when glab is not installed, so a GitHub-only reviewer's list still loads", async () => {
+  const { forge } = forgeReplaying([{ exitCode: null, spawnError: "spawn /usr/bin/glab ENOENT" }]);
+
+  assert.deepEqual(await forge.listChangeRequests(), []);
+});
+
 test("an MR reads by the viewer's own reviewer record, changed when the head commit is newer than it", async () => {
   const { forge } = forgeReplaying(LIST_REVIEWS);
 

plugins/guided-review/server/forge/gitlab.ts

@@ -4,7 +4,7 @@ import type { Draft, DraftLocation, LineRef } from "../../shared/drafts.ts";
 import type { CommandRunner } from "../command-runner.ts";
 import type { Verdict } from "../../shared/submit.ts";
 import type { AuthoredChangeRequest, CiState, ListedChangeRequest, ListedHost, ReviewerState, ReviewRequest } from "../../shared/inbox.ts";
-import { createCli, type Cli } from "./cli.ts";
+import { CliNotFoundError, createCli, type Cli } from "./cli.ts";
 import { GITHUB_HOST } from "./github.ts";
 import { CLONE_TIMEOUT_MS, COMMIT_READS_AT_ONCE, mapAtMost, MAX_BRANCH_CHANGE_REQUESTS, MAX_COMMITS, MAX_LINKED_ISSUES, latestOf, reviewStatusOf, unlistedHost, userOf } from "./common.ts";
 import { SubmitSteps } from "./submit-steps.ts";
@@ -904,7 +904,15 @@ export function createGitLabForge(options: GitLabForgeOptions): Forge {
     },
 
     async listChangeRequests(): Promise<ListedHost[]> {
-      const statuses = parseAuthStatus(await glab.report(["auth", "status", "--all"]));
+      let report: string;
+      try {
+        report = await glab.report(["auth", "status", "--all"]);
+      } catch (error) {
+        // GitLab has no host of its own to report as unlisted, so a reviewer without glab has none.
+        if (error instanceof CliNotFoundError) return [];
+        throw error;
+      }
+      const statuses = parseAuthStatus(report);
       return Promise.all(
         statuses.map(async ({ host, loggedIn, problem }): Promise<ListedHost> => {
           if (!loggedIn) {