jest: Prepare for eslint-plugin-jest upgrade.

There are just a few occurrences of these: jest/expect-expect: https://github.com/jest-community/eslint-plugin-jest/blob/master/docs/rules/expect-expect.md jest/no-try-expect https://github.com/jest-community/eslint-plugin-jest/blob/master/docs/rules/no-try-expect.md jest/no-standalone-expect https://github.com/jest-community/eslint-plugin-jest/blob/master/docs/rules/no-standalone-expect.md A small concern about `jest/no-standalone-expect` is noted in code comments.
zulip · Sep 16, 2020 · 3f9892d · 3f9892d
1 parent 9a144c5
commit 3f9892d
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Showing 5 changed files with 53 additions and 25 deletions.
diff --git a/src/__tests__/sentry-test.js b/src/__tests__/sentry-test.js
@@ -9,20 +9,33 @@ describe('sentry', () => {
     // we're specifically testing that its entry points can be used while it's
     // uninitialized.
     beforeEach(() => {
+      // This Jest lint rule is slightly concerning; its doc [1]
+      // claims that `expect` statements won't run if they're outside
+      // a `test` or `it` block. Empirically, here, that isn't true --
+      // changing the below assertion to its negation causes quite
+      // visible failure output from Jest.
+      //
+      // [1] https://github.com/jest-community/eslint-plugin-jest/blob/master/docs/rules/no-standalone-expect.md
+      // eslint-disable-next-line jest/no-standalone-expect
       expect(isSentryActive()).toBeFalse();
     });
 
     afterEach(() => {
+      // (see above)
+      // eslint-disable-next-line jest/no-standalone-expect
       expect(isSentryActive()).toBeFalse();
     });
 
     test('breadcrumbs', () => {
-      Sentry.addBreadcrumb({
-        message: 'test message',
-        level: Sentry.Severity.Debug,
-      });
+      expect(() => {
+        Sentry.addBreadcrumb({
+          message: 'test message',
+          level: Sentry.Severity.Debug,
+        });
+      }).not.toThrow();
     });
 
+    // eslint-disable-next-line jest/expect-expect
     test('exception reporting', () => {
       // The text here is intended to prevent some hypothetical future reader of
       // Sentry event logs dismissing the error as harmless expected noise, in

diff --git a/src/emoji/__tests__/data-test.js b/src/emoji/__tests__/data-test.js
@@ -1,4 +1,7 @@
 /* @flow strict-local */
+// Tell Jest to recognize `check` as a helper function that runs
+// assertions.
+/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect", "check"] }] */
 import { codeToEmojiMap, getFilteredEmojis } from '../data';
 
 // Prettier disabled in .prettierignore ; it misparses this file, apparently

diff --git a/src/message/__tests__/fetchActions-test.js b/src/message/__tests__/fetchActions-test.js
@@ -202,15 +202,14 @@ describe('fetchActions', () => {
         };
         fetch.mockResponseSuccess(JSON.stringify(response));
 
-        expect.assertions(2);
-        try {
-          await store.dispatch(
+        await expect(
+          store.dispatch(
             fetchMessages({ narrow: HOME_NARROW, anchor: 0, numBefore: 1, numAfter: 1 }),
-          );
-        } catch (e) {
+          ),
+        ).rejects.toThrow(
           // Update this with changes to the message string or error type.
-          expect(e.message).toBe('Active account not logged in');
-        }
+          new Error('Active account not logged in'),
+        );
 
         const actions = store.getActions();
 
@@ -255,15 +254,14 @@ describe('fetchActions', () => {
         };
         fetch.mockResponseSuccess(JSON.stringify(response));
 
-        expect.assertions(2);
-        try {
-          await store.dispatch(
+        await expect(
+          store.dispatch(
             fetchMessages({ narrow: HOME_NARROW, anchor: 0, numBefore: 1, numAfter: 1 }),
-          );
-        } catch (e) {
+          ),
+        ).rejects.toThrow(
           // Update this with changes to the error type.
-          expect(e).toBeInstanceOf(TypeError);
-        }
+          TypeError,
+        );
 
         const actions = store.getActions();
 
@@ -281,14 +279,11 @@ describe('fetchActions', () => {
 
         fetch.mockResponseFailure(fetchError);
 
-        expect.assertions(1);
-        try {
-          await store.dispatch(
+        await expect(
+          store.dispatch(
             fetchMessages({ narrow: HOME_NARROW, anchor: 0, numBefore: 1, numAfter: 1 }),
-          );
-        } catch (e) {
-          expect(e).toBe(fetchError);
-        }
+          ),
+        ).rejects.toThrow(fetchError);
       });
     });
 

diff --git a/src/presence/__tests__/heartbeat-test.js b/src/presence/__tests__/heartbeat-test.js
@@ -121,18 +121,31 @@ describe('Heartbeat', () => {
 
     for (const heartbeat of heartbeats) {
       // Tests should stop all their Heartbeats.
+      //
+      // This Jest lint rule is slightly concerning; its doc [1]
+      // claims that `expect` statements won't run if they're outside
+      // a `test` or `it` block. Empirically, here, that isn't true --
+      // changing the below assertion to its negation causes quite
+      // visible failure output from Jest.
+      //
+      // [1] https://github.com/jest-community/eslint-plugin-jest/blob/master/docs/rules/no-standalone-expect.md
+      // eslint-disable-next-line jest/no-standalone-expect
       expect(heartbeat.isActive()).toBeFalse();
       heartbeat.callback.mockClear();
     }
 
     // Stopped heartbeats may have timers running, but those timers should not
     // persist beyond their next firing...
     lolex.runOnlyPendingTimers();
+    // (see above, about lint rule)
+    // eslint-disable-next-line jest/no-standalone-expect
     expect(lolex.getTimerCount()).toBe(0);
 
     // ... and none of those _timer_ firings should result in a _callback_
     // firing.
     for (const heartbeat of heartbeats) {
+      // (see above, about lint rule)
+      // eslint-disable-next-line jest/no-standalone-expect
       expect(heartbeat.callback).not.toHaveBeenCalled();
     }
   });

diff --git a/src/utils/__tests__/internalLinks-test.js b/src/utils/__tests__/internalLinks-test.js
@@ -1,4 +1,8 @@
 /* @flow strict-local */
+// Tell Jest to recognize `expectStream` as a helper function that
+// runs assertions.
+/* eslint jest/expect-expect: ["error", { "assertFunctionNames": ["expect", "expectStream"] }] */
+
 import type { User } from '../../api/modelTypes';
 import { streamNarrow, topicNarrow, groupNarrow, STARRED_NARROW } from '../narrow';
 import {