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docs(Path): clarify that zero-length contours are excluded from computeMetrics#180165

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Feb 24, 2026
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docs(Path): clarify that zero-length contours are excluded from computeMetrics#180165
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Add documentation clarifying that zero-length contours are not included in the PathMetrics returned by computeMetrics.

Fixes #179668

@github-actions github-actions Bot added the engine flutter/engine related. See also e: labels. label Dec 20, 2025

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This pull request adds documentation to Path.computeMetrics to clarify that zero-length contours are excluded from the results. The change is correct and improves the documentation. I have one minor suggestion to rephrase the added text for better conciseness and clarity.

Comment on lines +3191 to +3193
/// Zero-length contours (where the start and end points are the same, such as
/// `Path()..lineTo(0, 0)`) are not included in the returned [PathMetrics].
/// Only contours with a positive length will have a corresponding [PathMetric].

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medium

This is a great clarification. To make it a bit more concise and place the main rule first for better readability, consider rephrasing this paragraph.

  /// Only contours with a positive length will have a corresponding [PathMetric].
  /// Zero-length contours are not included, such as one created by
  /// `Path()..lineTo(0, 0)`.

@Piinks Piinks requested a review from gaaclarke February 24, 2026 15:44

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sounds good to me, thanks

@gaaclarke gaaclarke added the autosubmit Merge PR when tree becomes green via auto submit App label Feb 24, 2026
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autosubmit label was removed for flutter/flutter/180165, because The base commit of the PR is older than 7 days and can not be merged. Please merge the latest changes from the main into this branch and resubmit the PR.

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autosubmit label was removed for flutter/flutter/180165, because This PR has not met approval requirements for merging. The PR author is not a member of flutter-hackers and needs 1 more review(s) in order to merge this PR.

  • Merge guidelines: A PR needs at least one approved review if the author is already part of flutter-hackers or two member reviews if the author is not a flutter-hacker before re-applying the autosubmit label. Reviewers: If you left a comment approving, please use the "approve" review action instead.

@gaaclarke gaaclarke added the autosubmit Merge PR when tree becomes green via auto submit App label Feb 24, 2026
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autosubmit label was removed for flutter/flutter/180165, because This PR has not met approval requirements for merging. The PR author is not a member of flutter-hackers and needs 1 more review(s) in order to merge this PR.

  • Merge guidelines: A PR needs at least one approved review if the author is already part of flutter-hackers or two member reviews if the author is not a flutter-hacker before re-applying the autosubmit label. Reviewers: If you left a comment approving, please use the "approve" review action instead.

@gaaclarke gaaclarke requested review from b-luk and flar February 24, 2026 16:51
@gaaclarke gaaclarke added the autosubmit Merge PR when tree becomes green via auto submit App label Feb 24, 2026
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flar commented Feb 24, 2026

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This should have included a test to make sure that we continue to observe this condition. It may be forgotten later when we replace the path implementation.

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flar commented Feb 24, 2026

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Issue filed to add a test case: #182854

Merged via the queue into flutter:master with commit 2d06a6e Feb 24, 2026
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@flutter-dashboard flutter-dashboard Bot removed the autosubmit Merge PR when tree becomes green via auto submit App label Feb 24, 2026
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Roll Flutter from dad6f9d4107a to b31548feb941 (39 revisions)

flutter/flutter@dad6f9d...b31548f

2026-02-25 mdebbar@google.com [web] Fix failure on Firefox 148 (flutter/flutter#182855)
2026-02-25 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from KfPgw04T0OEADLJA5... to XI0Ax7fbtYE4XKYAQ... (flutter/flutter#182887)
2026-02-25 50643541+Mairramer@users.noreply.github.com Use AnimationStyle curve and reverseCurve in ModalBottomSheet animation (flutter/flutter#181403)
2026-02-25 engine-flutter-autoroll@skia.org Roll Dart SDK from fd3dce5b6a4e to 5c57e75f1102 (9 revisions) (flutter/flutter#182801)
2026-02-25 98614782+auto-submit[bot]@users.noreply.github.com Reverts "refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (#182697)" (flutter/flutter#182879)
2026-02-25 ahmedsameha1@gmail.com Make sure that an AnimatedSlide doesn't crash in 0x0 environment (flutter/flutter#181535)
2026-02-24 jmccandless@google.com Reland Standardize on Test* widgets in *_tester.dart files (flutter/flutter#182632)
2026-02-24 nhan13574@gmail.com docs(Path): clarify that zero-length contours are excluded from computeMetrics (flutter/flutter#180165)
2026-02-24 mdebbar@google.com Fix typo in assert message (flutter/flutter#182843)
2026-02-24 matej.knopp@gmail.com [win32] Fix overflow in TaskRunnerWindow. (flutter/flutter#182822)
2026-02-24 abadasamuelosp@gmail.com feat: Add --no-uninstall flag to flutter test for integration tests (flutter/flutter#182714)
2026-02-24 74057391+jhonathanqz@users.noreply.github.com Rename noFrequencyBasedMinification to useFrequencyBasedMinification (flutter/flutter#182684)
2026-02-24 60122246+xiaowei-guan@users.noreply.github.com [Impeller] Fix fail to render pixel buffer texture on Linux (flutter/flutter#181656)
2026-02-24 15619084+vashworth@users.noreply.github.com Remove FlutterFramework app migration (flutter/flutter#182100)
2026-02-24 engine-flutter-autoroll@skia.org Roll Packages from 12b43a1 to 062c8d4 (5 revisions) (flutter/flutter#182839)
2026-02-24 mdebbar@google.com [web] Run webparagraph tests in CI (flutter/flutter#182092)
2026-02-24 jason-simmons@users.noreply.github.com Fix a race in EmbedderTest.CanSpecifyCustomUITaskRunner (flutter/flutter#182649)
2026-02-24 srawlins@google.com flutter_tools: Use a super-parameter in several missed cases (flutter/flutter#182581)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Replace more references to `flutter/engine` with `flutter/flutter` (flutter/flutter#182654)
2026-02-24 50643541+Mairramer@users.noreply.github.com Carousel: Migration from Scrollable+Viewport to CustomScrollView (flutter/flutter#182475)
2026-02-24 97480502+b-luk@users.noreply.github.com Refactor impellerc_main to better organize some of its logic (flutter/flutter#182783)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Remove unused `getPluginList ` (flutter/flutter#182660)
2026-02-24 34465683+rkishan516@users.noreply.github.com Refactor: Remove material from ticker provider test (flutter/flutter#181697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 26eebffe12bd to f44d7db68805 (3 revisions) (flutter/flutter#182821)
2026-02-24 34465683+rkishan516@users.noreply.github.com refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (flutter/flutter#182697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 7dad66aae75a to 26eebffe12bd (5 revisions) (flutter/flutter#182810)
2026-02-24 pokepsi@gmail.com Update roadmap for 2026 (flutter/flutter#182798)
2026-02-24 fluttergithubbot@gmail.com Marks Windows tool_tests_commands_1_2 to be unflaky (flutter/flutter#179670)
2026-02-23 zhongliu88889@gmail.com [web] scroll iOS iframe text input into view (flutter/flutter#179759)
2026-02-23 Mail@maikwild.de Fix textscaler clamp assertion error (flutter/flutter#181716)
2026-02-23 engine-flutter-autoroll@skia.org Roll Skia from 9a5a3c92c336 to 7dad66aae75a (4 revisions) (flutter/flutter#182779)
2026-02-23 116356835+AbdeMohlbi@users.noreply.github.com Move more getters from userMessages class to the appropriate places (flutter/flutter#182656)
2026-02-23 engine-flutter-autoroll@skia.org Manual roll Dart SDK from f8fac50475b8 to fd3dce5b6a4e (6 revisions) (flutter/flutter#182768)
2026-02-23 15619084+vashworth@users.noreply.github.com Copy Flutter framework to Add to App FlutterPluginRgistrant (flutter/flutter#182523)
2026-02-23 mr-peipei@web.de Add progress indicator to artifact downloads (flutter/flutter#181808)
2026-02-23 47866232+chunhtai@users.noreply.github.com Clarify batch release mode requirements (flutter/flutter#182228)
2026-02-23 mdebbar@google.com [web] Remove --disable-gpu from flutter chrome tests (flutter/flutter#182618)
2026-02-23 jwren@google.com running-apps: update running-apps to use Duration.ago() (flutter/flutter#182172)
2026-02-23 kevmoo@users.noreply.github.com Refactor bin/ shell scripts for better performance and safety (flutter/flutter#182674)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC louisehsu@google.com,stuartmorgan@google.com on the revert to ensure that a human
is aware of the problem.

...
ahmedsameha1 pushed a commit to ahmedsameha1/flutter that referenced this pull request Feb 27, 2026
…teMetrics (flutter#180165)

Add documentation clarifying that zero-length contours are not included
in the PathMetrics returned by computeMetrics.

Fixes flutter#179668

Co-authored-by: gaaclarke <30870216+gaaclarke@users.noreply.github.com>
okorohelijah pushed a commit to okorohelijah/packages that referenced this pull request Mar 26, 2026
…r#11116)

Roll Flutter from dad6f9d4107a to b31548feb941 (39 revisions)

flutter/flutter@dad6f9d...b31548f

2026-02-25 mdebbar@google.com [web] Fix failure on Firefox 148 (flutter/flutter#182855)
2026-02-25 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from KfPgw04T0OEADLJA5... to XI0Ax7fbtYE4XKYAQ... (flutter/flutter#182887)
2026-02-25 50643541+Mairramer@users.noreply.github.com Use AnimationStyle curve and reverseCurve in ModalBottomSheet animation (flutter/flutter#181403)
2026-02-25 engine-flutter-autoroll@skia.org Roll Dart SDK from fd3dce5b6a4e to 5c57e75f1102 (9 revisions) (flutter/flutter#182801)
2026-02-25 98614782+auto-submit[bot]@users.noreply.github.com Reverts "refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (#182697)" (flutter/flutter#182879)
2026-02-25 ahmedsameha1@gmail.com Make sure that an AnimatedSlide doesn't crash in 0x0 environment (flutter/flutter#181535)
2026-02-24 jmccandless@google.com Reland Standardize on Test* widgets in *_tester.dart files (flutter/flutter#182632)
2026-02-24 nhan13574@gmail.com docs(Path): clarify that zero-length contours are excluded from computeMetrics (flutter/flutter#180165)
2026-02-24 mdebbar@google.com Fix typo in assert message (flutter/flutter#182843)
2026-02-24 matej.knopp@gmail.com [win32] Fix overflow in TaskRunnerWindow. (flutter/flutter#182822)
2026-02-24 abadasamuelosp@gmail.com feat: Add --no-uninstall flag to flutter test for integration tests (flutter/flutter#182714)
2026-02-24 74057391+jhonathanqz@users.noreply.github.com Rename noFrequencyBasedMinification to useFrequencyBasedMinification (flutter/flutter#182684)
2026-02-24 60122246+xiaowei-guan@users.noreply.github.com [Impeller] Fix fail to render pixel buffer texture on Linux (flutter/flutter#181656)
2026-02-24 15619084+vashworth@users.noreply.github.com Remove FlutterFramework app migration (flutter/flutter#182100)
2026-02-24 engine-flutter-autoroll@skia.org Roll Packages from 12b43a1 to 062c8d4 (5 revisions) (flutter/flutter#182839)
2026-02-24 mdebbar@google.com [web] Run webparagraph tests in CI (flutter/flutter#182092)
2026-02-24 jason-simmons@users.noreply.github.com Fix a race in EmbedderTest.CanSpecifyCustomUITaskRunner (flutter/flutter#182649)
2026-02-24 srawlins@google.com flutter_tools: Use a super-parameter in several missed cases (flutter/flutter#182581)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Replace more references to `flutter/engine` with `flutter/flutter` (flutter/flutter#182654)
2026-02-24 50643541+Mairramer@users.noreply.github.com Carousel: Migration from Scrollable+Viewport to CustomScrollView (flutter/flutter#182475)
2026-02-24 97480502+b-luk@users.noreply.github.com Refactor impellerc_main to better organize some of its logic (flutter/flutter#182783)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Remove unused `getPluginList ` (flutter/flutter#182660)
2026-02-24 34465683+rkishan516@users.noreply.github.com Refactor: Remove material from ticker provider test (flutter/flutter#181697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 26eebffe12bd to f44d7db68805 (3 revisions) (flutter/flutter#182821)
2026-02-24 34465683+rkishan516@users.noreply.github.com refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (flutter/flutter#182697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 7dad66aae75a to 26eebffe12bd (5 revisions) (flutter/flutter#182810)
2026-02-24 pokepsi@gmail.com Update roadmap for 2026 (flutter/flutter#182798)
2026-02-24 fluttergithubbot@gmail.com Marks Windows tool_tests_commands_1_2 to be unflaky (flutter/flutter#179670)
2026-02-23 zhongliu88889@gmail.com [web] scroll iOS iframe text input into view (flutter/flutter#179759)
2026-02-23 Mail@maikwild.de Fix textscaler clamp assertion error (flutter/flutter#181716)
2026-02-23 engine-flutter-autoroll@skia.org Roll Skia from 9a5a3c92c336 to 7dad66aae75a (4 revisions) (flutter/flutter#182779)
2026-02-23 116356835+AbdeMohlbi@users.noreply.github.com Move more getters from userMessages class to the appropriate places (flutter/flutter#182656)
2026-02-23 engine-flutter-autoroll@skia.org Manual roll Dart SDK from f8fac50475b8 to fd3dce5b6a4e (6 revisions) (flutter/flutter#182768)
2026-02-23 15619084+vashworth@users.noreply.github.com Copy Flutter framework to Add to App FlutterPluginRgistrant (flutter/flutter#182523)
2026-02-23 mr-peipei@web.de Add progress indicator to artifact downloads (flutter/flutter#181808)
2026-02-23 47866232+chunhtai@users.noreply.github.com Clarify batch release mode requirements (flutter/flutter#182228)
2026-02-23 mdebbar@google.com [web] Remove --disable-gpu from flutter chrome tests (flutter/flutter#182618)
2026-02-23 jwren@google.com running-apps: update running-apps to use Duration.ago() (flutter/flutter#182172)
2026-02-23 kevmoo@users.noreply.github.com Refactor bin/ shell scripts for better performance and safety (flutter/flutter#182674)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC louisehsu@google.com,stuartmorgan@google.com on the revert to ensure that a human
is aware of the problem.

...
mboetger pushed a commit to mboetger/flutter that referenced this pull request Mar 26, 2026
…teMetrics (flutter#180165)

Add documentation clarifying that zero-length contours are not included
in the PathMetrics returned by computeMetrics.

Fixes flutter#179668

Co-authored-by: gaaclarke <30870216+gaaclarke@users.noreply.github.com>
creatorpiyush pushed a commit to creatorpiyush/packages that referenced this pull request Jun 10, 2026
…r#11116)

Roll Flutter from dad6f9d4107a to b31548feb941 (39 revisions)

flutter/flutter@dad6f9d...b31548f

2026-02-25 mdebbar@google.com [web] Fix failure on Firefox 148 (flutter/flutter#182855)
2026-02-25 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from KfPgw04T0OEADLJA5... to XI0Ax7fbtYE4XKYAQ... (flutter/flutter#182887)
2026-02-25 50643541+Mairramer@users.noreply.github.com Use AnimationStyle curve and reverseCurve in ModalBottomSheet animation (flutter/flutter#181403)
2026-02-25 engine-flutter-autoroll@skia.org Roll Dart SDK from fd3dce5b6a4e to 5c57e75f1102 (9 revisions) (flutter/flutter#182801)
2026-02-25 98614782+auto-submit[bot]@users.noreply.github.com Reverts "refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (#182697)" (flutter/flutter#182879)
2026-02-25 ahmedsameha1@gmail.com Make sure that an AnimatedSlide doesn't crash in 0x0 environment (flutter/flutter#181535)
2026-02-24 jmccandless@google.com Reland Standardize on Test* widgets in *_tester.dart files (flutter/flutter#182632)
2026-02-24 nhan13574@gmail.com docs(Path): clarify that zero-length contours are excluded from computeMetrics (flutter/flutter#180165)
2026-02-24 mdebbar@google.com Fix typo in assert message (flutter/flutter#182843)
2026-02-24 matej.knopp@gmail.com [win32] Fix overflow in TaskRunnerWindow. (flutter/flutter#182822)
2026-02-24 abadasamuelosp@gmail.com feat: Add --no-uninstall flag to flutter test for integration tests (flutter/flutter#182714)
2026-02-24 74057391+jhonathanqz@users.noreply.github.com Rename noFrequencyBasedMinification to useFrequencyBasedMinification (flutter/flutter#182684)
2026-02-24 60122246+xiaowei-guan@users.noreply.github.com [Impeller] Fix fail to render pixel buffer texture on Linux (flutter/flutter#181656)
2026-02-24 15619084+vashworth@users.noreply.github.com Remove FlutterFramework app migration (flutter/flutter#182100)
2026-02-24 engine-flutter-autoroll@skia.org Roll Packages from 12b43a1 to 062c8d4 (5 revisions) (flutter/flutter#182839)
2026-02-24 mdebbar@google.com [web] Run webparagraph tests in CI (flutter/flutter#182092)
2026-02-24 jason-simmons@users.noreply.github.com Fix a race in EmbedderTest.CanSpecifyCustomUITaskRunner (flutter/flutter#182649)
2026-02-24 srawlins@google.com flutter_tools: Use a super-parameter in several missed cases (flutter/flutter#182581)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Replace more references to `flutter/engine` with `flutter/flutter` (flutter/flutter#182654)
2026-02-24 50643541+Mairramer@users.noreply.github.com Carousel: Migration from Scrollable+Viewport to CustomScrollView (flutter/flutter#182475)
2026-02-24 97480502+b-luk@users.noreply.github.com Refactor impellerc_main to better organize some of its logic (flutter/flutter#182783)
2026-02-24 116356835+AbdeMohlbi@users.noreply.github.com Remove unused `getPluginList ` (flutter/flutter#182660)
2026-02-24 34465683+rkishan516@users.noreply.github.com Refactor: Remove material from ticker provider test (flutter/flutter#181697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 26eebffe12bd to f44d7db68805 (3 revisions) (flutter/flutter#182821)
2026-02-24 34465683+rkishan516@users.noreply.github.com refactor: remove material in context_menu_controller_test, icon_test, list_wheel_scroll_view_test, media_query_test, platform_menu_bar_test (flutter/flutter#182697)
2026-02-24 engine-flutter-autoroll@skia.org Roll Skia from 7dad66aae75a to 26eebffe12bd (5 revisions) (flutter/flutter#182810)
2026-02-24 pokepsi@gmail.com Update roadmap for 2026 (flutter/flutter#182798)
2026-02-24 fluttergithubbot@gmail.com Marks Windows tool_tests_commands_1_2 to be unflaky (flutter/flutter#179670)
2026-02-23 zhongliu88889@gmail.com [web] scroll iOS iframe text input into view (flutter/flutter#179759)
2026-02-23 Mail@maikwild.de Fix textscaler clamp assertion error (flutter/flutter#181716)
2026-02-23 engine-flutter-autoroll@skia.org Roll Skia from 9a5a3c92c336 to 7dad66aae75a (4 revisions) (flutter/flutter#182779)
2026-02-23 116356835+AbdeMohlbi@users.noreply.github.com Move more getters from userMessages class to the appropriate places (flutter/flutter#182656)
2026-02-23 engine-flutter-autoroll@skia.org Manual roll Dart SDK from f8fac50475b8 to fd3dce5b6a4e (6 revisions) (flutter/flutter#182768)
2026-02-23 15619084+vashworth@users.noreply.github.com Copy Flutter framework to Add to App FlutterPluginRgistrant (flutter/flutter#182523)
2026-02-23 mr-peipei@web.de Add progress indicator to artifact downloads (flutter/flutter#181808)
2026-02-23 47866232+chunhtai@users.noreply.github.com Clarify batch release mode requirements (flutter/flutter#182228)
2026-02-23 mdebbar@google.com [web] Remove --disable-gpu from flutter chrome tests (flutter/flutter#182618)
2026-02-23 jwren@google.com running-apps: update running-apps to use Duration.ago() (flutter/flutter#182172)
2026-02-23 kevmoo@users.noreply.github.com Refactor bin/ shell scripts for better performance and safety (flutter/flutter#182674)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC louisehsu@google.com,stuartmorgan@google.com on the revert to ensure that a human
is aware of the problem.

...
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Path.computeMetrics inconsistency

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