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paint: Do not unwrap in stop_fling_if_needed to fix pinch zoom panic#42350

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yezhizhen merged 1 commit intoservo:mainfrom
yezhizhen:fix-touch-panic
Feb 5, 2026
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paint: Do not unwrap in stop_fling_if_needed to fix pinch zoom panic#42350
yezhizhen merged 1 commit intoservo:mainfrom
yezhizhen:fix-touch-panic

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@yezhizhen yezhizhen commented Feb 5, 2026

Touch sequence may have already been removed before stopping potential fling during Paint update.
This can happen when we touch up both fingers quickly after the touch move,
before updates are performed in Paint.
We should not play with fire and unwrap.

Testing: Tested with Android, ohos and WebDriver. I can no longer replicate the panic with Pinch Zoom.
Fixes: #42320, which is very verbose but provides the entire story.

@servo-highfive servo-highfive added the S-awaiting-review There is new code that needs to be reviewed. label Feb 5, 2026
@yezhizhen yezhizhen changed the title paint: Don't play with fire when stop fling paint: Don't play with fire when stop flinging Feb 5, 2026
Signed-off-by: Euclid Ye <[email protected]>
@yezhizhen yezhizhen added the T-android Do a try run on Android label Feb 5, 2026
@github-actions github-actions bot removed the T-android Do a try run on Android label Feb 5, 2026
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github-actions bot commented Feb 5, 2026

🔨 Triggering try run (#21697999343) for Android

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github-actions bot commented Feb 5, 2026

✨ Try run (#21697999343) succeeded.

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yezhizhen commented Feb 5, 2026

Tested on Android too. It also had the panic, which is gone with this PR.
cc @kongbai1996

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Can you add the test from the issue as WPT test?

@servo-highfive servo-highfive removed the S-awaiting-review There is new code that needs to be reviewed. label Feb 5, 2026
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yezhizhen commented Feb 5, 2026

@TimvdLippe Thanks. I wanted to add a crash test, but it seems pinch zoom cannot be triggered in headless window somehow: #42320 (comment)

That would require investigation.

@yezhizhen yezhizhen added the T-linux-wpt Do a try run of the WPT label Feb 5, 2026
@github-actions github-actions bot removed the T-linux-wpt Do a try run of the WPT label Feb 5, 2026
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github-actions bot commented Feb 5, 2026

🔨 Triggering try run (#21701260800) for Linux (WPT)

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github-actions bot commented Feb 5, 2026

Test results for linux-wpt from try job (#21701260800):

Flaky unexpected result (30)
  • OK /IndexedDB/idbfactory-open-error-properties.any.html
    • PASS [expected FAIL] subtest: Properties of error event from failed open()
  • OK /IndexedDB/idbfactory-open-error-properties.any.worker.html
    • PASS [expected FAIL] subtest: Properties of error event from failed open()
  • OK /_mozilla/mozilla/getBoundingClientRect.html (#39668)
    • FAIL [expected PASS] subtest: getBoundingClientRect 1

      assert_equals: expected 62 but got 60.35
      

  • CRASH [expected PASS] /_mozilla/shadow-dom/move-element-with-ua-shadow-tree-crash.html (#39473)
  • CRASH [expected OK] /_webgl/conformance2/wasm/readpixels-2gb-in-4gb-wasm-memory.html
  • OK /css/css-fonts/generic-family-keywords-001.html (#37467)
    • FAIL [expected PASS] subtest: @font-face matching for quoted and unquoted generic(nastaliq)

      assert_equals: quoted generic(nastaliq) matches  @font-face rule expected 50 but got 30
      

  • OK [expected ERROR] /fetch/fetch-later/quota/same-origin-iframe/accumulated-oversized-payload.https.window.html (#41705)
  • ERROR [expected OK] /fetch/fetch-later/quota/same-origin-iframe/multiple-iframes.https.window.html (#35176)
  • OK [expected ERROR] /focus/focus-event-after-switching-iframes.sub.html (#40368)
  • OK /html/browsers/browsing-the-web/navigating-across-documents/008.html (#24456)
    • PASS [expected FAIL] subtest: Link with onclick form submit to javascript url and href navigation
  • OK /html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/load-pageshow-events-window-open.html (#28691)
    • PASS [expected FAIL] subtest: load event does not fire on window.open('about:blank')
  • OK /html/browsers/browsing-the-web/navigating-across-documents/navigation-unload-cross-origin.sub.window.html (#29056)
    • FAIL [expected PASS] subtest: Cross-origin navigation started from unload handler must be ignored

      promise_test: Unhandled rejection with value: object "SecurityError: The operation is insecure."
      

  • OK /html/semantics/document-metadata/the-meta-element/pragma-directives/attr-meta-http-equiv-refresh/allow-scripts-flag-changing-1.html (#39694)
    • PASS [expected FAIL] subtest: Meta refresh is blocked by the allow-scripts sandbox flag at its creation time, not when refresh comes due
  • OK /html/semantics/document-metadata/the-meta-element/pragma-directives/attr-meta-http-equiv-refresh/allow-scripts-flag-changing-2.html (#39703)
    • PASS [expected FAIL] subtest: Meta refresh of the original iframe is not blocked if moved into a sandboxed iframe
  • TIMEOUT /html/semantics/embedded-content/media-elements/autoplay-disabled-by-feature-policy.https.sub.html (#41221)
    • TIMEOUT [expected FAIL] subtest: Feature-Policy header: autoplay "none" disallows same-origin iframes.

      Test timed out
      

  • OK /html/semantics/embedded-content/media-elements/media_fragment_seek.html (#24114)
    • FAIL [expected PASS] subtest: Video should seek to time specified in media fragment syntax

      assert_equals: expected 3 but got 0
      

  • OK [expected TIMEOUT] /html/semantics/embedded-content/media-elements/src_object_blob.html (#40340)
    • PASS [expected TIMEOUT] subtest: HTMLMediaElement.srcObject blob
  • TIMEOUT [expected OK] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_navigate_other_frame_popup.sub.html (#39702)
    • TIMEOUT [expected FAIL] subtest: Sandboxed iframe can not navigate other frame's popup

      Test timed out
      

  • OK /html/semantics/forms/form-submission-0/jsurl-form-submit.tentative.html (#36489)
    • PASS [expected FAIL] subtest: Verifies that form submissions scheduled inside javascript: urls take precedence over the javascript: url's return value.
  • OK /html/semantics/scripting-1/the-script-element/execution-timing/077.html (#22139)
    • FAIL [expected PASS] subtest: adding several types of scripts through the DOM and removing some of them confuses scheduler

      assert_array_equals: expected property 1 to be "Script #1 ran" but got "Script #3 ran" (expected array ["Script #2 ran", "Script #1 ran", "Script #3 ran", "Script #4 ran"] got ["Script #2 ran", "Script #3 ran", "Script #4 ran", "Script #1 ran"])
      

  • TIMEOUT [expected OK] /html/user-activation/navigation-state-reset-sameorigin.html
    • TIMEOUT [expected PASS] subtest: Post-navigation state reset.

      Test timed out
      

  • OK /preload/link-header-preload-delay-onload.html (#39622)
    • FAIL [expected PASS] subtest: Makes sure that Link headers preload resources and block window.onload after resource discovery

      assert_true: expected true got false
      

  • OK /resource-timing/buffer-full-add-then-clear.html (#40819)
    • PASS [expected FAIL] subtest: Test that if the buffer is cleared after entries were added to the secondary buffer, those entries make it into the primary one
  • TIMEOUT /trusted-types/trusted-types-navigation.html?31-35 (#38034)
    • TIMEOUT [expected PASS] subtest: Navigate a frame via form-submission with javascript:-urls in report-only mode.

      Test timed out
      

    • NOTRUN [expected TIMEOUT] subtest: Navigate a frame via form-submission with javascript:-urls w/ default policy in report-only mode.
  • OK /webdriver/tests/classic/execute_async_script/objects.py
    • FAIL [expected PASS] subtest: test_object

      AssertionError: no such window (404): No such window
      

  • OK /webdriver/tests/classic/execute_script/arguments.py
    • FAIL [expected PASS] subtest: test_null

      AssertionError: no such window (404): No such window
      

  • OK /webdriver/tests/classic/execute_script/cyclic.py
    • FAIL [expected PASS] subtest: test_collection_self_reference

      assert 404 == 500
      

  • OK /webdriver/tests/classic/get_current_url/iframe.py
    • FAIL [expected PASS] subtest: test_iframe

      webdriver.error.NoSuchWindowException: no such window (404): No such window
      

  • OK [expected ERROR] /webxr/render_state_update.https.html (#27535)
  • OK /xhr/send-redirect.htm (#32026)
    • FAIL [expected PASS] subtest: XMLHttpRequest: send() - Redirects (basics) (302, GET, content.py)

      assert_equals: expected (string) "GET" but got (object) null
      

Stable unexpected results that are known to be intermittent (32)
  • OK /IndexedDB/idbcursor-continuePrimaryKey-exceptions.any.html (#39277)
    • FAIL [expected PASS] subtest: IDBCursor continuePrimaryKey() on object store cursor

      assert_throws_dom: continuePrimaryKey() should throw if source is not an index function "function() {
              cursor.continuePrimaryKey(2, 2);
            }" threw object "TypeError: cursor.continuePrimaryKey is not a function" that is not a DOMException InvalidAccessError: property "code" is equal to undefined, expected 15
      

  • OK /IndexedDB/idbcursor-continuePrimaryKey-exceptions.any.worker.html (#39277)
    • FAIL [expected PASS] subtest: IDBCursor continuePrimaryKey() on object store cursor

      assert_throws_dom: continuePrimaryKey() should throw if source is not an index function "function() {
              cursor.continuePrimaryKey(2, 2);
            }" threw object "TypeError: cursor.continuePrimaryKey is not a function" that is not a DOMException InvalidAccessError: property "code" is equal to undefined, expected 15
      

  • OK /IndexedDB/idbobjectstore_getAll.any.html (#39276)
    • PASS [expected FAIL] subtest: Get all values with transaction.commit()
  • OK /IndexedDB/idbobjectstore_getAll.any.worker.html (#39400)
    • PASS [expected FAIL] subtest: Get all values with transaction.commit()
  • OK /IndexedDB/idbrequest-onupgradeneeded.any.html (#38895)
    • PASS [expected FAIL] subtest: transaction oncomplete ordering relative to open request onsuccess
  • OK /IndexedDB/idbrequest-onupgradeneeded.any.worker.html (#38971)
    • PASS [expected FAIL] subtest: transaction oncomplete ordering relative to open request onsuccess
  • OK /IndexedDB/key-conversion-exceptions.any.html (#39305)
    • FAIL [expected PASS] subtest: IDBCursor continue() method with throwing/invalid keys

      assert_throws_exactly: key conversion with throwing getter should rethrow function "() =&gt; {
            receiver[method](key);
          }" threw object "TypeError: receiver[method] is not a function" but we expected it to throw object "getter: throwing from getter"
      

    • FAIL [expected PASS] subtest: IDBCursor update() method with throwing/invalid keys

      assert_throws_exactly: throwing getter should rethrow during clone function "() =&gt; {
            cursor.update(value);
          }" threw object "TypeError: cursor.update is not a function" but we expected it to throw object "getter: throwing from getter"
      

  • OK /IndexedDB/key-conversion-exceptions.any.worker.html (#39284)
    • FAIL [expected PASS] subtest: IDBCursor continue() method with throwing/invalid keys

      assert_throws_exactly: key conversion with throwing getter should rethrow function "() =&gt; {
            receiver[method](key);
          }" threw object "TypeError: receiver[method] is not a function" but we expected it to throw object "getter: throwing from getter"
      

    • FAIL [expected PASS] subtest: IDBCursor update() method with throwing/invalid keys

      assert_throws_exactly: throwing getter should rethrow during clone function "() =&gt; {
            cursor.update(value);
          }" threw object "TypeError: cursor.update is not a function" but we expected it to throw object "getter: throwing from getter"
      

  • OK /IndexedDB/transaction-deactivation-timing.any.worker.html (#38808)
    • PASS [expected FAIL] subtest: New transactions are deactivated before next task
    • PASS [expected FAIL] subtest: New transactions from microtask are deactivated before next task
  • OK /_mozilla/css/offset_properties_inline.html (#40543)
    • PASS [expected FAIL] subtest: offsetTop
    • PASS [expected FAIL] subtest: offsetLeft
  • FAIL [expected PASS] /_mozilla/mozilla/sslfail.html (#10760)
  • TIMEOUT [expected OK] /_mozilla/mozilla/window_resize_event.html (#36741)
    • TIMEOUT [expected PASS] subtest: Popup onresize event fires after resizeTo

      Test timed out
      

  • OK /content-security-policy/frame-ancestors/frame-ancestors-path-ignored.window.html (#36468)
    • PASS [expected FAIL] subtest: A 'frame-ancestors' CSP directive with a URL that includes a path should be ignored.
  • OK /css/css-cascade/layer-font-face-override.html (#35935)
    • FAIL [expected PASS] subtest: @font-face override update with appended sheet 2

      assert_equals: expected "80px" but got "38.3166666666667px"
      

  • OK /css/css-fonts/generic-family-keywords-003.html (#38994)
    • FAIL [expected PASS] subtest: @font-face matching for quoted and unquoted serif (drawing text in a canvas)

      assert_equals: quoted serif matches  @font-face rule expected 40 but got 125
      

    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted sans-serif (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted fantasy (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted monospace (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted system-ui (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted math (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted generic(fangsong) (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted generic(khmer-mul) (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted generic(nastaliq) (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted ui-serif (drawing text in a canvas)
  • OK /css/cssom-view/offsetTopLeft-border-box.html (#40826)
    • PASS [expected FAIL] subtest: container: 0
    • PASS [expected FAIL] subtest: container: 1
  • OK /custom-elements/form-associated/ElementInternals-setFormValue.html (#29174)
    • PASS [expected FAIL] subtest: Single value - empty name exists
    • PASS [expected FAIL] subtest: Single value - Non-empty name exists
    • PASS [expected FAIL] subtest: Null value should submit nothing
    • PASS [expected FAIL] subtest: Multiple values - name content attribute is ignored
    • PASS [expected FAIL] subtest: setFormValue with an empty FormData should submit nothing
    • PASS [expected FAIL] subtest: Newline normalization - \r\n in name (urlencoded)
    • PASS [expected FAIL] subtest: Newline normalization - \n in value (formdata)
    • PASS [expected FAIL] subtest: Newline normalization - \r\n in value (urlencoded)
    • PASS [expected FAIL] subtest: Newline normalization - \r\n in value (formdata)
    • PASS [expected FAIL] subtest: Newline normalization - \r\n in filename (urlencoded)
    • And 5 more unexpected results...
  • OK /fetch/metadata/generated/css-font-face.https.sub.tentative.html (#32732)
    • FAIL [expected PASS] subtest: sec-fetch-mode

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."
      

    • PASS [expected FAIL] subtest: sec-fetch-dest
    • FAIL [expected PASS] subtest: sec-fetch-user

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."
      

  • OK /fetch/metadata/generated/css-font-face.sub.tentative.html (#34624)
    • PASS [expected FAIL] subtest: sec-fetch-storage-access - Not sent to non-trustworthy same-origin destination
    • FAIL [expected PASS] subtest: sec-fetch-storage-access - Not sent to non-trustworthy same-site destination

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."
      

  • OK /html/browsers/windows/embedded-opener-remove-frame.html (#23867)
    • FAIL [expected PASS] subtest: opener of discarded auxiliary browsing context

      assert_object_equals: property "get" expected function "function opener() {
          [native code]
      }" got function "function opener() {
          [native code]
      }"
      

  • TIMEOUT /html/semantics/embedded-content/media-elements/autoplay-allowed-by-feature-policy.https.sub.html (#41404)
    • TIMEOUT [expected PASS] subtest: Feature-Policy header: autoplay * allows same-origin iframes.

      Test timed out
      

  • TIMEOUT /html/semantics/embedded-content/media-elements/autoplay-default-feature-policy.https.sub.html (#41193)
    • PASS [expected TIMEOUT] subtest: Default "autoplay" feature policy ["self"] allows same-origin iframes.
  • OK /html/semantics/forms/form-submission-0/multipart-formdata.window.html (#28725)
    • PASS [expected FAIL] subtest: multipart/form-data: Basic File test (formdata event)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in name (normal form)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in name (formdata event)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in value (normal form)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in value (formdata event)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in filename (normal form)
    • PASS [expected FAIL] subtest: multipart/form-data: 0x00 in filename (formdata event)
    • PASS [expected FAIL] subtest: multipart/form-data: \n in value (normal form)
    • PASS [expected FAIL] subtest: multipart/form-data: \n in value (formdata event)
    • PASS [expected FAIL] subtest: multipart/form-data: \r\n in value (normal form)
    • And 19 more unexpected results...
  • OK /html/semantics/forms/form-submission-0/text-plain.window.html (#28687)
    • PASS [expected FAIL] subtest: text/plain: Basic File test (formdata event)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in name (normal form)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in name (formdata event)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in value (normal form)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in value (formdata event)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in filename (normal form)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in filename (formdata event)
    • PASS [expected FAIL] subtest: text/plain: \r\n in name (normal form)
    • PASS [expected FAIL] subtest: text/plain: \r\n in name (formdata event)
    • PASS [expected FAIL] subtest: text/plain: \r\n in value (normal form)
    • And 25 more unexpected results...
  • OK /html/semantics/forms/form-submission-0/urlencoded2.window.html (#28687)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: Basic File test (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in name (normal form)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in name (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in value (normal form)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in value (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in filename (normal form)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in filename (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: \r\n in name (normal form)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: \r\n in name (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: \r\n in value (normal form)
    • And 31 more unexpected results...
  • OK /html/webappapis/user-prompts/print-during-unload.html (#35944)
    • FAIL [expected PASS] subtest: print() during unload

      assert_array_equals: expected property 1 to be "destination" but got "error: window.print is not a function" (expected array ["start", "destination"] got ["start", "error: window.print is not a function"])
      

  • OK /navigation-timing/test-navigation-type-reload.html (#33334)
    • FAIL [expected PASS] subtest: Reload domComplete &gt; Original domComplete

      assert_true: Reload domComplete &gt; Original domComplete expected true got false
      

    • FAIL [expected PASS] subtest: Reload loadEventEnd &gt; Original loadEventEnd

      assert_true: Reload loadEventEnd &gt; Original loadEventEnd expected true got false
      

    • FAIL [expected PASS] subtest: Reload loadEventStart &gt; Original loadEventStart

      assert_true: Reload loadEventStart &gt; Original loadEventStart expected true got false
      

  • OK /resource-timing/test_resource_timing.html (#25720)
    • PASS [expected FAIL] subtest: window.performance.getEntriesByName() and window.performance.getEntriesByNameType() return same data (iframe)
    • PASS [expected NOTRUN] subtest: PerformanceEntry has correct name, initiatorType, startTime, and duration (link)
  • OK /resource-timing/test_resource_timing.https.html (#25216)
    • PASS [expected FAIL] subtest: window.performance.getEntriesByName() and window.performance.getEntriesByNameType() return same data (iframe)
    • FAIL [expected PASS] subtest: PerformanceEntry has correct name, initiatorType, startTime, and duration (img)

      assert_equals: expected 19.829999999999984 but got 19.83
      

  • OK /service-workers/service-worker/fetch-event.https.html (#36234)
    • PASS [expected FAIL] subtest: Service Worker falls back to network in fetch event with POST form
  • TIMEOUT [expected OK] /trusted-types/trusted-types-navigation.html?01-05 (#38975)
    • TIMEOUT [expected PASS] subtest: Navigate a window via anchor with javascript:-urls in report-only mode.

      Test timed out
      

    • NOTRUN [expected PASS] subtest: Navigate a window via anchor with javascript:-urls w/ default policy in report-only mode.
    • NOTRUN [expected PASS] subtest: Navigate a frame via anchor with javascript:-urls in enforcing mode.
  • TIMEOUT [expected OK] /webstorage/localstorage-about-blank-3P-iframe-opens-3P-window.partitioned.html (#29053)
    • TIMEOUT [expected PASS] subtest: StorageKey: test 3P about:blank window opened from a 3P iframe

      Test timed out
      

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github-actions bot commented Feb 5, 2026

✨ Try run (#21701260800) succeeded.

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jschwe commented Feb 5, 2026

I wonder how difficult it would be to add some unit-tests for the touch handler (with other components like script mocked). There's been quite a few issues with crashes due to wrong assumptions, so it might be worth to invest some time in adding comprehensive testing of this module. Not something in the scope of this PR, but perhaps something to think about for the future ...

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I would appreciate the title being slightly more descriptive, e.g. Fix crash with multiple concucrrent touchups, which seems to be what caused the issue?

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yezhizhen commented Feb 5, 2026

I wonder how difficult it would be to add some unit-tests for the touch handler (with other components like script mocked). There's been quite a few issues with crashes due to wrong assumptions, so it might be worth to invest some time in adding comprehensive testing of this module. Not something in the scope of this PR, but perhaps something to think about for the future ...

We have a roadmap to support all WPT touch tests coverage, which is also how the issue is found as we made progress. (As WebDriver operates much faster than human)

but it seems pinch zoom cannot be triggered in headless window somehow

Once we solve this newly found issue, we will have more test coverage.

@yezhizhen yezhizhen changed the title paint: Don't play with fire when stop flinging paint: Fix crash in stop_fling_if_needed due to race condition Feb 5, 2026
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I will remake the title. After walking through the flow again, this is actually not race condition, but a deterministic behaviour. Things here happen on the same thread.

@yezhizhen yezhizhen changed the title paint: Fix crash in stop_fling_if_needed due to race condition paint: Do not unwrap in stop_fling_if_needed Feb 5, 2026
@yezhizhen yezhizhen changed the title paint: Do not unwrap in stop_fling_if_needed paint: Do not unwrap in stop_fling_if_needed to fix Pinch Zoom panic Feb 5, 2026
@yezhizhen yezhizhen changed the title paint: Do not unwrap in stop_fling_if_needed to fix Pinch Zoom panic paint: Do not unwrap in stop_fling_if_needed to fix pinch zoom panic Feb 5, 2026
@yezhizhen yezhizhen added this pull request to the merge queue Feb 5, 2026
@servo-highfive servo-highfive added the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Feb 5, 2026
Merged via the queue into servo:main with commit edac9de Feb 5, 2026
90 checks passed
@yezhizhen yezhizhen deleted the fix-touch-panic branch February 5, 2026 10:05
@servo-highfive servo-highfive removed the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Feb 5, 2026
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Multi-Touch panic for a simple case

4 participants