fix: detect approvals when approval_state reports no rules

index.ts

@@ -5806,7 +5806,13 @@ async function getMergeRequestApprovalState(
     method: "GET",
   });
 
-  if (approvalStateResponse.status === 404) {
+  // 404 when the endpoint is unavailable; 402/403 when the instance or namespace is
+  // not licensed for approval rules, which are a paid-tier feature.
+  if (
+    approvalStateResponse.status === 404 ||
+    approvalStateResponse.status === 402 ||
+    approvalStateResponse.status === 403
+  ) {
     return getMergeRequestApprovalsFallback(projectId, mergeRequestIid);
   }
 
@@ -5820,6 +5826,22 @@ async function getMergeRequestApprovalState(
   );
   const approvedByUsernames = approvedByUsers.map(user => user.username);
 
+  // approval_state only reports approvals attributed to rules, so a project with no
+  // approval rules answers 200 with `rules: []` and yields no approvers even when
+  // someone has approved. Read /approvals in that case. A non-empty rules array means
+  // rules are in use and approval_state is authoritative, so no extra request is made
+  // there - including while an MR is still waiting for its first approval.
+  if ((parsedApprovalState.rules || []).length === 0) {
+    try {
+      const viaApprovals = await getMergeRequestApprovalsFallback(projectId, mergeRequestIid);
+      if ((viaApprovals.approved_by ?? []).length > 0) {
+        return viaApprovals;
+      }
+    } catch {
+      // /approvals unavailable as well - keep the approval_state answer below.
+    }
+  }
+
   return {
     ...parsedApprovalState,
     approved_by: approvedByUsers,

test/test-merge-request-approval-state-tools.ts

@@ -7,6 +7,7 @@ const MOCK_TOKEN = "glpat-mock-token-approval";
 const TEST_PROJECT_ID = "123";
 const TEST_MR_IID_WITH_FALLBACK = "88";
 const TEST_MR_IID_WITH_APPROVAL_STATE = "89";
+const TEST_MR_IID_WITHOUT_RULES = "90";
 
 async function callTool(
   toolName: string,
@@ -160,6 +161,43 @@ describe("merge request approval state tools", () => {
       }
     );
 
+    // A project without approval rules answers 200 with an empty rules array, while
+    // the approval itself is only visible on /approvals.
+    mockGitLab.addMockHandler(
+      "get",
+      `/projects/${TEST_PROJECT_ID}/merge_requests/${TEST_MR_IID_WITHOUT_RULES}/approval_state`,
+      (_req, res) => {
+        res.json({
+          approval_rules_overwritten: false,
+          rules: [],
+        });
+      }
+    );
+
+    mockGitLab.addMockHandler(
+      "get",
+      `/projects/${TEST_PROJECT_ID}/merge_requests/${TEST_MR_IID_WITHOUT_RULES}/approvals`,
+      (_req, res) => {
+        res.json({
+          approved: true,
+          user_has_approved: false,
+          user_can_approve: true,
+          approved_by: [
+            {
+              user: {
+                id: "35",
+                username: "sergey.kravchenya",
+                name: "Sergey Kravchenya",
+                state: "active",
+                avatar_url: "https://gitlab.mock/uploads/avatar.png",
+                web_url: "https://gitlab.mock/sergey.kravchenya",
+              },
+            },
+          ],
+        });
+      }
+    );
+
     await mockGitLab.start();
     mockGitLabUrl = mockGitLab.getUrl();
   });
@@ -188,6 +226,26 @@ describe("merge request approval state tools", () => {
     assert.strictEqual(result.approved_by[0].username, "sergey.kravchenya");
   });
 
+  test("finds approvers via approvals when approval_state reports no rules", async () => {
+    const result = await callTool(
+      "get_merge_request_approval_state",
+      {
+        project_id: TEST_PROJECT_ID,
+        merge_request_iid: TEST_MR_IID_WITHOUT_RULES,
+      },
+      {
+        GITLAB_API_URL: `${mockGitLabUrl}/api/v4`,
+        GITLAB_PERSONAL_ACCESS_TOKEN: MOCK_TOKEN,
+      }
+    );
+
+    assert.strictEqual(result.source_endpoint, "approvals");
+    assert.strictEqual(result.approved, true);
+    assert.deepStrictEqual(result.approved_by_usernames, ["sergey.kravchenya"]);
+    assert.ok(Array.isArray(result.approved_by));
+    assert.strictEqual(result.approved_by[0].username, "sergey.kravchenya");
+  });
+
   test("returns deduplicated approvers from approval_state rules", async () => {
     const result = await callTool(
       "get_merge_request_approval_state",