Switch from Jest to Vitest by t3chguy · Pull Request #5131 · matrix-org/matrix-js-sdk

t3chguy · 2026-01-09T13:43:46Z

Depends on #5136

Fairly simple transition:

@fetch-mock/jest -> @fetch-mock/vitest
jest -> vi mostly

Some smaller tweaks which should be obvious

Tests run much faster locally with significantly less memory pressure, in CI they go from about 3m -> 2m

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

This test failed when ran individually, same as after the clearAllMocks call Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

…ny other way Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

…ch-mock & fix typo Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

…sdk into t3chguy/vitest # Conflicts: # src/utils.ts

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

dbkr

~~Presumably this is not supposed to be the only change?~~Never mind, I'm being confused by github's UI where it only shows one file at a time if there are too many.

t3chguy · 2026-01-13T14:07:57Z

Presumably this is not supposed to be the only change?

Hm?

dbkr

Otherwise lgtm - phew, good to get this done!

dbkr · 2026-01-13T14:31:37Z

spec/unit/matrix-client.spec.ts

+        vi.mocked(client.http.authedRequest).mockImplementation(function () {
            return new Promise(() => {});
        });
-        client.stopClient();


Do we still need to do this or does vitest make it unnecessary?

Depends on the side of the test file, the thread gets discarded between tests but a huge test file may benefit from it. Unfortunately any unhandled exceptions (such as those from a fetch being aborted) can upset the test during cleanup.

Fair enough.

…chguy/vitest Signed-off-by: Michael Telatynski <7t3chguy@gmail.com> # Conflicts: # knip.ts # package.json # spec/integ/crypto/cross-signing.spec.ts # spec/integ/crypto/crypto.spec.ts # spec/integ/crypto/device-dehydration.spec.ts # spec/integ/crypto/history-sharing.spec.ts # spec/integ/crypto/megolm-backup.spec.ts # spec/integ/crypto/olm-utils.ts # spec/integ/crypto/rust-crypto.spec.ts # spec/integ/crypto/state-events.spec.ts # spec/integ/crypto/to-device-messages.spec.ts # spec/integ/crypto/verification.spec.ts # spec/integ/matrix-client-syncing-errors.spec.ts # spec/integ/rendezvous/MSC4108SignInWithQR.spec.ts # spec/integ/sliding-sync-sdk.spec.ts # spec/setupTests.ts # spec/test-utils/AccountDataAccumulator.ts # spec/test-utils/E2EKeyReceiver.ts # spec/test-utils/E2EKeyResponder.ts # spec/test-utils/E2EOTKClaimResponder.ts # spec/test-utils/SyncResponder.ts # spec/test-utils/mockEndpoints.ts # spec/unit/embedded.spec.ts # spec/unit/event-timeline-set.spec.ts # spec/unit/http-api/fetch.spec.ts # spec/unit/http-api/utils.spec.ts # spec/unit/login.spec.ts # spec/unit/matrix-client.spec.ts # spec/unit/matrixrtc/CallMembership.spec.ts # spec/unit/matrixrtc/MatrixRTCSession.spec.ts # spec/unit/matrixrtc/MembershipManager.spec.ts # spec/unit/matrixrtc/mocks.ts # spec/unit/oidc/authorize.spec.ts # spec/unit/oidc/register.spec.ts # spec/unit/oidc/tokenRefresher.spec.ts # spec/unit/rendezvous/MSC4108RendezvousSession.spec.ts # spec/unit/room-hierarchy.spec.ts # spec/unit/room-member.spec.ts # spec/unit/room.spec.ts # spec/unit/rust-crypto/KeyClaimManager.spec.ts # spec/unit/rust-crypto/OutgoingRequestProcessor.spec.ts # spec/unit/rust-crypto/PerSessionKeyBackupDownloader.spec.ts # spec/unit/rust-crypto/backup.spec.ts # spec/unit/rust-crypto/rust-crypto.spec.ts # spec/unit/secret-storage.spec.ts # spec/unit/webrtc/groupCall.spec.ts # yarn.lock

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

BillCarsonFr

Looked at the voip part. Thanks for going through that 🙌

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

t3chguy mentioned this pull request Jan 12, 2026

Update fetch-mock-jest to @fetch-mock/jest #5136

Merged

t3chguy added 18 commits January 12, 2026 10:52

Skip unwritten tests

ec01847

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Tidy jest fake timers

c2f2421

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Remove unnecessary sessionStorage mock

711eef0

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Improve types

8b00d8f

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Improve async assertions

69dbad7

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Improve error assertions

2f16d86

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Improve object assertions

0390968

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Remove assertion testing unclear mock

e9ac3a8

This test failed when ran individually, same as after the clearAllMocks call Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Avoid awaiting non-thenables

dca403d

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Pass nop function when stubbing out console, vitest won't accept it a…

93004d6

…ny other way Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Remove unnecessary mock which causes tests to fail after updating fet…

95b2303

…ch-mock & fix typo Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Fix mistaken assertions not testing all values in array

eea6a5b

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Fix hidden non-running tests in room.spec.ts

e77cfe3

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Update fetch-mock-jest to @fetch-mock/jest

758439b

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Delint

e6b8995

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Make knip happier

3a5a369

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Make knip happier 2.0

ed0620c

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Delint

68e2ee0

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

t3chguy force-pushed the t3chguy/vitest branch from aa0562f to 466de41 Compare January 13, 2026 09:42

t3chguy changed the base branch from develop to t3chguy/fetch-mock January 13, 2026 09:42

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Switch from Jest to Vitest

54ee44c

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

t3chguy force-pushed the t3chguy/vitest branch from 466de41 to 54ee44c Compare January 13, 2026 11:17

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t3chguy added 3 commits January 13, 2026 11:28

Iterate

6745ddf

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Delint

f9c3c78

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

Merge branch 't3chguy/fetch-mock' of github.com:matrix-org/matrix-js-…

bdcbf5b

…sdk into t3chguy/vitest # Conflicts: # src/utils.ts

github-actions bot deployed to PR Documentation Preview January 13, 2026 11:38 View deployment

Fix CI

6027bbb

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

t3chguy requested review from dbkr and removed request for a team January 13, 2026 12:29

Fix slow test reporter

1c7f6ee

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

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dbkr reviewed Jan 13, 2026

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t3chguy requested a review from dbkr January 13, 2026 14:08

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andybalaam requested review from andybalaam and removed request for kaylendog and richvdh January 13, 2026 14:47

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Base automatically changed from t3chguy/fetch-mock to develop January 14, 2026 13:08

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Fix bad merge conflict resolution

4296794

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

t3chguy enabled auto-merge January 15, 2026 10:23

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github-merge-queue bot removed this pull request from the merge queue due to failed status checks Jan 15, 2026

t3chguy added this pull request to the merge queue Jan 15, 2026

github-merge-queue bot removed this pull request from the merge queue due to failed status checks Jan 15, 2026

Fix babel config

826f906

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

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t3chguy enabled auto-merge January 15, 2026 11:14

t3chguy added this pull request to the merge queue Jan 15, 2026

Merged via the queue into develop with commit 899cdb0 Jan 15, 2026
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t3chguy deleted the t3chguy/vitest branch January 15, 2026 11:34

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Switch from Jest to Vitest#5131

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