fix(widget_inspector): add null check for flex factor property to prevent exception by muhammadkamel · Pull Request #167890 · flutter/flutter

muhammadkamel · 2025-04-27T06:22:49Z

Null check exception appears while opening Widget Inspector as the attached screenshots and video.

flex_factor_issue.mp4

Pre-launch Checklist

I read the Contributor Guide and followed the process outlined there for submitting PRs.
I read the Tree Hygiene wiki page, which explains my responsibilities.
I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
I signed the CLA.
I listed at least one issue that this PR fixes in the description above.
I updated/added relevant documentation (doc comments with ///).
I added new tests to check the change I am making, or this PR is test-exempt.
I followed the breaking change policy and added Data Driven Fixes where supported.
All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

flutter-dashboard · 2025-04-27T06:22:52Z

It looks like this pull request may not have tests. Please make sure to add tests or get an explicit test exemption before merging.

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

Reviewers: Read the Tree Hygiene page and make sure this patch meets those guidelines before LGTMing.If you believe this PR qualifies for a test exemption, contact "@test-exemption-reviewer" in the #hackers channel in Discord (don't just cc them here, they won't see it!). The test exemption team is a small volunteer group, so all reviewers should feel empowered to ask for tests, without delegating that responsibility entirely to the test exemption group.

justinmc · 2025-04-29T22:08:03Z

@muhammadkamel Would you be able to add a test for this? Ideally you could write a test that reproduces the null check exception on master, and then expect expect(tester.takeException(), isNull);.

muhammadkamel · 2025-04-29T22:12:44Z

@justinmc

Yeah! I will write a test for it, and update the branch.

…update tests

muhammadkamel · 2025-04-30T09:15:29Z

@justinmc

I have added tests and handle null value

muhammadkamel · 2025-05-05T09:22:52Z

@bkonyi
@justinmc
Could you please review this?

bkonyi

Sorry for the delay, was OOO. LGTM, just need one more reviewer.

muhammadkamel · 2025-05-15T15:01:08Z

@bkonyi

No worries! Mind tagging someone who could help with the final review?

bkonyi · 2025-05-15T15:04:41Z

@bkonyi

No worries! Mind tagging someone who could help with the final review?

Yup, I've added @justinmc as a secondary reviewer.

However, you do have a failure in the test you added that would prevent this from being submitted:

03:14 +3098 ~3: /b/s/w/ir/x/w/flutter/packages/flutter/test/widgets/widget_inspector_test.dart: layout explorer ext.flutter.inspector.getLayoutExplorerNode for RenderBox with FlexParentData
══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following TestFailure was thrown running a test:
Expected: not null
  Actual: <null>

When the exception was thrown, this was the stack:
#4      _TestWidgetInspectorService.runTests.<anonymous closure>.<anonymous closure> (file:///b/s/w/ir/x/w/flutter/packages/flutter/test/widgets/widget_inspector_test.dart:5139:9)
<asynchronous suspension>
#5      testWidgets.<anonymous closure>.<anonymous closure> (package:flutter_test/src/widget_tester.dart:193:15)
<asynchronous suspension>
#6      TestWidgetsFlutterBinding._runTestBody (package:flutter_test/src/binding.dart:1064:5)
<asynchronous suspension>
<asynchronous suspension>
(elided one frame from package:stack_trace)

This was caught by the test expectation on the following line:
  file:///b/s/w/ir/x/w/flutter/packages/flutter/test/widgets/widget_inspector_test.dart line 5139
The test description was:
  ext.flutter.inspector.getLayoutExplorerNode for RenderBox with FlexParentData
════════════════════════════════════════════════════════════════════════════════════════════════════

bkonyi · 2025-05-21T14:15:15Z

Thanks @muhammadkamel, it looks like that fixed the failing test. I've merged in master to try and rerun the last failing check that's likely an infrastructure issue on our end.

auto-submit · 2025-05-21T14:26:07Z

autosubmit label was removed for flutter/flutter/167890, because - The status or check suite Google testing has failed. Please fix the issues identified (or deflake) before re-applying this label.

…y to prevent exception (flutter/flutter#167890)

Roll Flutter from 9a78af5 to 33cdd8e (60 revisions) flutter/flutter@9a78af5...33cdd8e 2025-05-21 [email protected] Feat: Add persistentFooterDecoration for scaffold (flutter/flutter#167524) 2025-05-21 [email protected] Removed repeated entry in `CHANGELOG.md` (flutter/flutter#165273) 2025-05-21 [email protected] [native assets] Graduate to preview (flutter/flutter#169194) 2025-05-21 [email protected] [Impeller] disable gl ext render to texture on vivante. (flutter/flutter#169153) 2025-05-21 [email protected] fix(widget_inspector): add null check for flex factor property to prevent exception (flutter/flutter#167890) 2025-05-21 [email protected] Unpin leak_tracker. (flutter/flutter#169079) 2025-05-21 [email protected] runtime/dart: fuchsia::io::MODE_TYPE_FILE -> V_TYPE_FILE (flutter/flutter#168952) 2025-05-21 [email protected] Remove `isExplicitPackageDependenciesEnabled: true`, it is the default. (flutter/flutter#169156) 2025-05-21 [email protected] Roll pub packages (flutter/flutter#169181) 2025-05-20 [email protected] Fix the issue with Tooltip (flutter/flutter#168546) 2025-05-20 [email protected] [native assets] Roll dependencies (flutter/flutter#169073) 2025-05-20 [email protected] Add documentation for experimental branches, update artifacts. (flutter/flutter#169109) 2025-05-20 [email protected] [flutter_tool] Remove unused environment flags in JS compiler (flutter/flutter#169097) 2025-05-20 [email protected] Add support for hiding widget subtrees from the widget inspector (flutter/flutter#169007) 2025-05-20 [email protected] Roll Fuchsia GN SDK from jsZSHIOmQAs3URvWU... to _tkqOQZ2qB5CxDe57... (flutter/flutter#169113) 2025-05-20 [email protected] Skip running `Linux fuchsia_test` on non-master channel. (flutter/flutter#169106) 2025-05-19 [email protected] Roll Skia from c97451da059f to 13a299964c9f (61 revisions) (flutter/flutter#169099) 2025-05-19 [email protected] Shared element transition for predictive back (flutter/flutter#154718) 2025-05-19 [email protected] Fix DDC library bundle format test files to correctly pass flags (flutter/flutter#169095) 2025-05-19 [email protected] Clean up redundant new line in the GPUSurfaceGLSkia constructor initializer list (flutter/flutter#169031) 2025-05-19 [email protected] Fix keyboard_hot_restart_ios flakes (flutter/flutter#168518) 2025-05-19 [email protected] fix android studio lint about lambda argument (flutter/flutter#168901) 2025-05-19 [email protected] Fix typo in gpu_surface_gl_impeller.cc (flutter/flutter#168395) 2025-05-19 [email protected] Modernize system executable detection across components (flutter/flutter#169018) 2025-05-19 [email protected] Update documentation for `Size` and `Rect` classes (flutter/flutter#168031) 2025-05-19 [email protected] Update the `RangeSlider` widget to the 2024 Material Design appearance (flutter/flutter#163736) 2025-05-19 [email protected] Roll Packages from 58d4016 to af0b9a9 (5 revisions) (flutter/flutter#169075) 2025-05-19 [email protected] Only bundle assets and plugins from transitive closure of dependencies (flutter/flutter#160443) 2025-05-19 [email protected] Make FlutterGeneratedPluginSwiftPackage an Xcode root package (flutter/flutter#168789) 2025-05-19 [email protected] docs: Update deprecation message for Slider.year2023 (flutter/flutter#169053) 2025-05-18 [email protected] macOS: port ResizeSynchronizer to Swift (flutter/flutter#168959) 2025-05-17 [email protected] Roll Dart SDK from dc323ec0c1a3 to 7c40eba6bf77 (3 revisions) (flutter/flutter#169024) 2025-05-17 [email protected] [tool] Remove unused `reportNullSafety` getter (flutter/flutter#168484) 2025-05-17 [email protected] Add flag to skip bundling extension safe builds in frameworks for DDM (flutter/flutter#168955) 2025-05-16 [email protected] Fixes Navigator calls onPopInvokedWithResult when onPopPage return false (flutter/flutter#168567) 2025-05-16 [email protected] [hcpp/hc] Fix talkback for HC and HCPP Android platform views (flutter/flutter#168939) 2025-05-16 [email protected] [Impeller] separate immutable sampler descriptors. (flutter/flutter#169011) 2025-05-16 [email protected] TextField magnifier stuck on long press cancel (flutter/flutter#167881) 2025-05-16 [email protected] Fix Chip delete button semantic bounds (flutter/flutter#168310) 2025-05-16 [email protected] Roll Fuchsia Linux SDK from Jj-iDG5uPOsFgY2_H... to XtPp9bBW49iDJ0wbA... (flutter/flutter#169009) 2025-05-16 [email protected] [ Widget Preview ] Refactor `@Preview()` detection and code generation (flutter/flutter#168307) 2025-05-16 [email protected] Roll Packages from 2dff621 to 58d4016 (2 revisions) (flutter/flutter#168999) 2025-05-16 [email protected] Remove `unittests` from `windows_host_engine` GN targets. (flutter/flutter#168991) 2025-05-16 [email protected] Fix bug with debugging support code not getting injected on edge devices (flutter/flutter#168073) 2025-05-16 [email protected] Roll Dart SDK from a1db62a5dd14 to dc323ec0c1a3 (4 revisions) (flutter/flutter#168989) 2025-05-16 [email protected] Resolve Cupertino textstyle in MaterialBasedCupertinoThemeData (flutter/flutter#167597) ...

…y to prevent exception (flutter/flutter#167890)

fix: flex factor null check exception.

d4ee1a3

github-actions bot added the framework flutter/packages/flutter repository. See also f: labels. label Apr 27, 2025

muhammadkamel added 4 commits April 27, 2025 09:24

Merge branch 'master' into fix/flex-factor-null-check

c1c6c2c

Update widget_inspector.dart

e48ac14

Update widget_inspector.dart

38025c8

Merge branch 'master' into fix/flex-factor-null-check

d692023

muhammadkamel added 7 commits April 30, 2025 01:13

Merge branch 'master' into fix/flex-factor-null-check

ca18dd1

fix(widget_inspector): ensure flexFactor defaults to 0 when null and …

ee37c6a

…update tests

test(widget_inspector): ensure no exceptions are thrown

589965b

Merge branch 'master' into fix/flex-factor-null-check

2f62183

Merge branch 'master' into fix/flex-factor-null-check

60ff43e

Merge branch 'master' into fix/flex-factor-null-check

f4144dd

Merge branch 'master' into fix/flex-factor-null-check

2a84a2e

muhammadkamel added 3 commits April 30, 2025 13:45

Merge branch 'master' into fix/flex-factor-null-check

05612d1

Merge branch 'master' into fix/flex-factor-null-check

848e4ad

Merge branch 'master' into fix/flex-factor-null-check

2805573

muhammadkamel changed the title ~~fix: flex factor null check exception.~~ fix [Widget Inspector]: flex factor null check exception. May 5, 2025

Merge branch 'master' into fix/flex-factor-null-check

f09c302

muhammadkamel changed the title ~~fix [Widget Inspector]: flex factor null check exception.~~ fix(widget_inspector): add null check for flex factor property to prevent exception May 12, 2025

Merge branch 'master' into fix/flex-factor-null-check

0204fee

bkonyi requested review from bkonyi and justinmc May 15, 2025 14:38

bkonyi approved these changes May 15, 2025

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muhammadkamel and others added 2 commits May 21, 2025 02:54

Refactor _TestWidgetInspectorService to simplify parentData checks

2493ac4

Merge branch 'master' into fix/flex-factor-null-check

680f0f7

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Merge branch 'master' into fix/flex-factor-null-check

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Merged via the queue into flutter:master with commit dd671fa May 21, 2025
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Roll Flutter from 9a78af5eb067 to dd671fae53d3 (56 revisions) flutter/packages#9301

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…y to prevent exception (flutter/flutter#167890)

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Roll Flutter from 9a78af5eb067 to 534b250a562c (58 revisions) flutter/packages#9303

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

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Roll Flutter from 9a78af5eb067 to f7354da75b27 (59 revisions) flutter/packages#9304

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…y to prevent exception (flutter/flutter#167890)

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Roll Flutter from 9a78af5eb067 to 33cdd8ef31dc (60 revisions) flutter/packages#9305

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

muhammadkamel mentioned this pull request May 25, 2025

[widget_inspector] Toggle Select Widget mode: Null check operator used on a null value #167612

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 15, 2025

dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

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dd671fa fix(widget_inspector): add null check for flex factor propert…

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…y to prevent exception (flutter/flutter#167890)

muhammadkamel deleted the fix/flex-factor-null-check branch August 18, 2025 02:44

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fix(widget_inspector): add null check for flex factor property to prevent exception#167890

fix(widget_inspector): add null check for flex factor property to prevent exception#167890
auto-submit[bot] merged 23 commits intoflutter:masterfrom
muhammadkamel:fix/flex-factor-null-check

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muhammadkamel commented Apr 27, 2025

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