Change order of end trace and persist pending traces between requests

Author: Mrtenz

packages/examples/packages/preinstalled/snap.manifest.json

@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "iQIQNMXYMDnEaXBghIesd9jKKklaaW/szrGut57SCDc=",
+    "shasum": "3ngRXZHVyqZB3sk6u9Hpj2V4SUjrhxb6D/aqesFSmeY=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",

packages/examples/packages/preinstalled/src/index.test.tsx

@@ -125,16 +125,27 @@ describe('onRpcRequest', () => {
     });
   });
 
-  describe('trace', () => {
+  describe('startTrace + endTrace', () => {
     it('starts and ends a trace', async () => {
       const { request } = await installSnap();
 
       const response = await request({
-        method: 'trace',
+        method: 'startTrace',
       });
 
-      expect(response).toRespondWith(null);
-      expect(response).toTrace({
+      expect(response).toRespondWith({
+        /* eslint-disable @typescript-eslint/naming-convention */
+        _traceId: expect.any(String),
+        _spanId: expect.any(String),
+        /* eslint-enable @typescript-eslint/naming-convention */
+      });
+
+      const endResponse = await request({
+        method: 'endTrace',
+      });
+
+      expect(endResponse).toRespondWith(null);
+      expect(endResponse).toTrace({
         name: 'Test Snap Trace',
       });
     });

packages/examples/packages/preinstalled/src/index.tsx

@@ -97,22 +97,6 @@ export const onRpcRequest: OnRpcRequestHandler = async ({ request }) => {
       });
     }
 
-    case 'trace': {
-      await snap.request({
-        method: 'snap_startTrace',
-        params: {
-          name: 'Test Snap Trace',
-        },
-      });
-
-      return await snap.request({
-        method: 'snap_endTrace',
-        params: {
-          name: 'Test Snap Trace',
-        },
-      });
-    }
-
     default:
       throw new MethodNotFoundError({ method: request.method });
   }

packages/snaps-simulation/src/store/trackables.test.ts

@@ -1,4 +1,4 @@
-import type { TrackedError, TrackedEvent } from './trackables';
+import type { TrackablesState, TrackedError, TrackedEvent } from './trackables';
 import { trackablesSlice, trackError } from './trackables';
 
 describe('trackablesSlice', () => {
@@ -107,6 +107,51 @@ describe('trackablesSlice', () => {
       expect(state.traces[0]).toStrictEqual(trace);
     });
 
+    it('works in last in first out order', () => {
+      const initialState: TrackablesState = {
+        events: [],
+        errors: [],
+        traces: [],
+        pendingTraces: [
+          {
+            id: '123',
+            name: 'Pending Trace',
+            tags: {
+              'test-tag': 'test-value',
+            },
+          },
+          {
+            id: '123',
+            name: 'Pending Trace',
+            tags: {
+              'other-tag': 'other-value',
+            },
+          },
+        ],
+      };
+
+      const trace = {
+        id: '123',
+        name: 'Pending Trace',
+      };
+
+      const state = trackablesSlice.reducer(
+        initialState,
+        trackablesSlice.actions.endTrace(trace),
+      );
+
+      expect(state.pendingTraces).toHaveLength(1);
+      expect(state.pendingTraces[0].id).toBe('123');
+      expect(state.traces).toHaveLength(1);
+      expect(state.traces[0]).toStrictEqual({
+        id: '123',
+        name: 'Pending Trace',
+        tags: {
+          'other-tag': 'other-value',
+        },
+      });
+    });
+
     it('does not modify state if trace is not found in pending traces', () => {
       const initialState = {
         events: [],

packages/snaps-simulation/src/store/trackables.ts

@@ -65,7 +65,7 @@ export const trackablesSlice = createSlice({
     },
     endTrace: (state, action: PayloadAction<EndTraceParams>) => {
       const endTrace = castDraft(action.payload);
-      const index = state.pendingTraces.findIndex(
+      const index = state.pendingTraces.findLastIndex(
         (pendingTrace) =>
           pendingTrace.id === endTrace.id &&
           pendingTrace.name === endTrace.name,
@@ -81,7 +81,6 @@ export const trackablesSlice = createSlice({
       state.events = [];
       state.errors = [];
       state.traces = [];
-      state.pendingTraces = [];
     },
   },
 });