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Merged
merged 4 commits into from
Oct 17, 2025
Merged

[DevTools] Compute environment names for the timeline #34892

merged 4 commits into from
Oct 17, 2025
+155 −77

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@sebmarkbage
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Stacked on #34885.

This refactors the timeline to store not just an id but a complex object for each step. This will later represent a group of boundaries.

Each timeline step is assigned an environment name. We pick the last environment name (assumed to have resolved last) from the union of the parent and child environment names. I.e. a child step is considered to be blocked by the parent so if a child isn't blocked on any environment name it still gets marked as the parent's environment name.

In a follow up, I'd like to reorder the document order timeline based on environment names to favor loading everything in one environment before the next.

@sebmarkbage sebmarkbage requested a review from eps1lon October 17, 2025 03:31
@meta-cla meta-cla bot added the CLA Signed label Oct 17, 2025
@github-actions github-actions bot added the React Core Team Opened by a member of the React Core Team label Oct 17, 2025
@sebmarkbage sebmarkbage mentioned this pull request Oct 17, 2025
Merged
eps1lon
eps1lon approved these changes Oct 17, 2025
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packages/react-devtools-shared/src/devtools/store.js
const environmentNameStringID = operations[i++];
environmentNames.push(stringTable[environmentNameStringID]);
const environmentName = stringTable[environmentNameStringID];
if (environmentName != null) {
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Can this ever be undefined?

@sebmarkbage sebmarkbage merged commit a083344 into facebook:main Oct 17, 2025
14 of 15 checks passed
sebmarkbage added a commit that referenced this pull request Oct 17, 2025
@sebmarkbage
[DevTools] Assign a different color and label based on environment (#…
3a66917 
…34893)

Stacked on #34892.

In the timeline scrubber each timeline entry gets a label and color
assigned based on the environment computed for that step.

In the rects, we find the timeline step that this boundary is part of
and use that environment to assign a color. This is slightly different
than picking from the boundary itself since it takes into account parent
boundaries.

In the "suspended by" section we color each entry individually based on
the environment that spawned the I/O.

<img width="790" height="813" alt="Screenshot 2025-10-17 at 12 18 56 AM"
src="https://github.com/user-attachments/assets/c902b1fb-0992-4e24-8e94-a97ca8507551"
/>
@nextjs-bot nextjs-bot mentioned this pull request Oct 19, 2025
Merged
sebmarkbage pushed a commit to vercel/next.js that referenced this pull request Oct 20, 2025
@nextjs-bot
Upgrade React from 1324e1bb-20251016 to 58bdc0bb-20251019 (#85072)
0601503 
[diff
facebook/react@1324e1bb...58bdc0bb](facebook/react@1324e1b...58bdc0b)

<details>
<summary>React upstream changes</summary>

- facebook/react#34911
- facebook/react#34907
- facebook/react#34906
- facebook/react#34898
- facebook/react#34893
- facebook/react#34892
- facebook/react#34885
- facebook/react#34881
- facebook/react#34894
- facebook/react#34880
- facebook/react#34849
- facebook/react#34900
- facebook/react#34887

</details>
@hoxyq hoxyq mentioned this pull request Oct 20, 2025
Merged
hoxyq added a commit that referenced this pull request Oct 20, 2025
@hoxyq
React DevTools 7.0.0 -> 7.0.1 (#34926)
3cde211 
Full list of changes:

* Text layout fixes for stack traces with badges
([eps1lon](https://github.com/eps1lon) in
[#34925](#34925))
* chore: read from build/COMMIT_SHA fle as fallback for commit hash
([hoxyq](https://github.com/hoxyq) in
[#34915](#34915))
* fix: dont ship source maps for css in prod builds
([hoxyq](https://github.com/hoxyq) in
[#34913](#34913))
* Lower case "rsc stream" debug info
([sebmarkbage](https://github.com/sebmarkbage) in
[#34921](#34921))
* BuiltInCallSite should have padding-left
([sebmarkbage](https://github.com/sebmarkbage) in
[#34922](#34922))
* Show the Suspense boundary name in the rect if there's no overlap
([sebmarkbage](https://github.com/sebmarkbage) in
[#34918](#34918))
* Don't attach filtered IO to grandparent Suspense
([eps1lon](https://github.com/eps1lon) in
[#34916](#34916))
* Infer name from stack if it's the generic "lazy" name
([sebmarkbage](https://github.com/sebmarkbage) in
[#34907](#34907))
* Use same Suspense naming heuristics when reconnecting
([eps1lon](https://github.com/eps1lon) in
[#34898](#34898))
* Assign a different color and label based on environment
([sebmarkbage](https://github.com/sebmarkbage) in
[#34893](#34893))
* Compute environment names for the timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[#34892](#34892))
* Don't highlight the root rect if no roots has unique suspenders
([sebmarkbage](https://github.com/sebmarkbage) in
[#34885](#34885))
* Highlight the rect when the corresponding timeline bean is hovered
([sebmarkbage](https://github.com/sebmarkbage) in
[#34881](#34881))
* Repeat the "name" if there's no short description in groups
([sebmarkbage](https://github.com/sebmarkbage) in
[#34894](#34894))
* Tweak the rects design and create multi-environment color scheme
([sebmarkbage](https://github.com/sebmarkbage) in
[#34880](#34880))
* Adjust the rects size by one pixel smaller
([sebmarkbage](https://github.com/sebmarkbage) in
[#34876](#34876))
* Remove steps title from scrubber
([sebmarkbage](https://github.com/sebmarkbage) in
[#34878](#34878))
* Include some sub-pixel precision in rects
([sebmarkbage](https://github.com/sebmarkbage) in
[#34873](#34873))
* Don't pluralize if already plural
([sebmarkbage](https://github.com/sebmarkbage) in
[#34870](#34870))
* Don't try to load anonymous or empty urls
([sebmarkbage](https://github.com/sebmarkbage) in
[#34869](#34869))
* Add inspection button to Suspense tab
([sebmarkbage](https://github.com/sebmarkbage) in
[#34867](#34867))
* Don't select on hover ([sebmarkbage](https://github.com/sebmarkbage)
in [#34860](#34860))
* Don't highlight on timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[#34861](#34861))
* The bridge event types should only be defined in one direction
([sebmarkbage](https://github.com/sebmarkbage) in
[#34859](#34859))
* Attempt at a better "unique suspender" text
([sebmarkbage](https://github.com/sebmarkbage) in
[#34854](#34854))
* Track whether a boundary is currently suspended and make transparent
([sebmarkbage](https://github.com/sebmarkbage) in
[#34853](#34853))
* Don't hide overflow rectangles
([sebmarkbage](https://github.com/sebmarkbage) in
[#34852](#34852))
* Measure text nodes ([sebmarkbage](https://github.com/sebmarkbage) in
[#34851](#34851))
* Don't measure fallbacks when suspended
([sebmarkbage](https://github.com/sebmarkbage) in
[#34850](#34850))
* Filter out built-in stack frames
([sebmarkbage](https://github.com/sebmarkbage) in
[#34828](#34828))
* Exclude Suspense boundaries in hidden Activity
([eps1lon](https://github.com/eps1lon) in
[#34756](#34756))
* Group consecutive suspended by rows by the same name
([sebmarkbage](https://github.com/sebmarkbage) in
[#34830](#34830))
* Preserve the original index when sorting suspended by
([sebmarkbage](https://github.com/sebmarkbage) in
[#34829](#34829))
* Don't show the root as being non-compliant
([sebmarkbage](https://github.com/sebmarkbage) in
[#34827](#34827))
* Ignore suspense boundaries, without visual representation, in the
timeline ([sebmarkbage](https://github.com/sebmarkbage) in
[#34824](#34824))
* Explicitly say which id to scroll to and only once
([sebmarkbage](https://github.com/sebmarkbage) in
[#34823](#34823))
* devtools: fix ellipsis truncation for key values
([sophiebits](https://github.com/sophiebits) in
[#34796](#34796))
* fix(devtools): remove duplicated "Display density" field in General
settings ([Anatole-Godard](https://github.com/Anatole-Godard) in
[#34792](#34792))
* Gate SuspenseTab ([hoxyq](https://github.com/hoxyq) in
[#34754](#34754))
* Release `<ViewTransition />` to Canary
([eps1lon](https://github.com/eps1lon) in
[#34712](#34712))
github-actions bot pushed a commit to code/lib-react that referenced this pull request Oct 24, 2025
@pull
React DevTools 7.0.0 -> 7.0.1 (facebook#34926)
3adcdcf 
Full list of changes:

* Text layout fixes for stack traces with badges
([eps1lon](https://github.com/eps1lon) in
[facebook#34925](facebook#34925))
* chore: read from build/COMMIT_SHA fle as fallback for commit hash
([hoxyq](https://github.com/hoxyq) in
[facebook#34915](facebook#34915))
* fix: dont ship source maps for css in prod builds
([hoxyq](https://github.com/hoxyq) in
[facebook#34913](facebook#34913))
* Lower case "rsc stream" debug info
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34921](facebook#34921))
* BuiltInCallSite should have padding-left
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34922](facebook#34922))
* Show the Suspense boundary name in the rect if there's no overlap
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34918](facebook#34918))
* Don't attach filtered IO to grandparent Suspense
([eps1lon](https://github.com/eps1lon) in
[facebook#34916](facebook#34916))
* Infer name from stack if it's the generic "lazy" name
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34907](facebook#34907))
* Use same Suspense naming heuristics when reconnecting
([eps1lon](https://github.com/eps1lon) in
[facebook#34898](facebook#34898))
* Assign a different color and label based on environment
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34893](facebook#34893))
* Compute environment names for the timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34892](facebook#34892))
* Don't highlight the root rect if no roots has unique suspenders
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34885](facebook#34885))
* Highlight the rect when the corresponding timeline bean is hovered
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34881](facebook#34881))
* Repeat the "name" if there's no short description in groups
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34894](facebook#34894))
* Tweak the rects design and create multi-environment color scheme
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34880](facebook#34880))
* Adjust the rects size by one pixel smaller
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34876](facebook#34876))
* Remove steps title from scrubber
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34878](facebook#34878))
* Include some sub-pixel precision in rects
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34873](facebook#34873))
* Don't pluralize if already plural
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34870](facebook#34870))
* Don't try to load anonymous or empty urls
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34869](facebook#34869))
* Add inspection button to Suspense tab
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34867](facebook#34867))
* Don't select on hover ([sebmarkbage](https://github.com/sebmarkbage)
in [facebook#34860](facebook#34860))
* Don't highlight on timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34861](facebook#34861))
* The bridge event types should only be defined in one direction
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34859](facebook#34859))
* Attempt at a better "unique suspender" text
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34854](facebook#34854))
* Track whether a boundary is currently suspended and make transparent
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34853](facebook#34853))
* Don't hide overflow rectangles
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34852](facebook#34852))
* Measure text nodes ([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34851](facebook#34851))
* Don't measure fallbacks when suspended
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34850](facebook#34850))
* Filter out built-in stack frames
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34828](facebook#34828))
* Exclude Suspense boundaries in hidden Activity
([eps1lon](https://github.com/eps1lon) in
[facebook#34756](facebook#34756))
* Group consecutive suspended by rows by the same name
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34830](facebook#34830))
* Preserve the original index when sorting suspended by
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34829](facebook#34829))
* Don't show the root as being non-compliant
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34827](facebook#34827))
* Ignore suspense boundaries, without visual representation, in the
timeline ([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34824](facebook#34824))
* Explicitly say which id to scroll to and only once
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34823](facebook#34823))
* devtools: fix ellipsis truncation for key values
([sophiebits](https://github.com/sophiebits) in
[facebook#34796](facebook#34796))
* fix(devtools): remove duplicated "Display density" field in General
settings ([Anatole-Godard](https://github.com/Anatole-Godard) in
[facebook#34792](facebook#34792))
* Gate SuspenseTab ([hoxyq](https://github.com/hoxyq) in
[facebook#34754](facebook#34754))
* Release `<ViewTransition />` to Canary
([eps1lon](https://github.com/eps1lon) in
[facebook#34712](facebook#34712))

DiffTrain build for [3cde211](facebook@3cde211)
github-actions bot pushed a commit to code/lib-react that referenced this pull request Oct 24, 2025
@pull
React DevTools 7.0.0 -> 7.0.1 (facebook#34926)
5901f42 
Full list of changes:

* Text layout fixes for stack traces with badges
([eps1lon](https://github.com/eps1lon) in
[facebook#34925](facebook#34925))
* chore: read from build/COMMIT_SHA fle as fallback for commit hash
([hoxyq](https://github.com/hoxyq) in
[facebook#34915](facebook#34915))
* fix: dont ship source maps for css in prod builds
([hoxyq](https://github.com/hoxyq) in
[facebook#34913](facebook#34913))
* Lower case "rsc stream" debug info
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34921](facebook#34921))
* BuiltInCallSite should have padding-left
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34922](facebook#34922))
* Show the Suspense boundary name in the rect if there's no overlap
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34918](facebook#34918))
* Don't attach filtered IO to grandparent Suspense
([eps1lon](https://github.com/eps1lon) in
[facebook#34916](facebook#34916))
* Infer name from stack if it's the generic "lazy" name
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34907](facebook#34907))
* Use same Suspense naming heuristics when reconnecting
([eps1lon](https://github.com/eps1lon) in
[facebook#34898](facebook#34898))
* Assign a different color and label based on environment
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34893](facebook#34893))
* Compute environment names for the timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34892](facebook#34892))
* Don't highlight the root rect if no roots has unique suspenders
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34885](facebook#34885))
* Highlight the rect when the corresponding timeline bean is hovered
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34881](facebook#34881))
* Repeat the "name" if there's no short description in groups
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34894](facebook#34894))
* Tweak the rects design and create multi-environment color scheme
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34880](facebook#34880))
* Adjust the rects size by one pixel smaller
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34876](facebook#34876))
* Remove steps title from scrubber
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34878](facebook#34878))
* Include some sub-pixel precision in rects
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34873](facebook#34873))
* Don't pluralize if already plural
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34870](facebook#34870))
* Don't try to load anonymous or empty urls
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34869](facebook#34869))
* Add inspection button to Suspense tab
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34867](facebook#34867))
* Don't select on hover ([sebmarkbage](https://github.com/sebmarkbage)
in [facebook#34860](facebook#34860))
* Don't highlight on timeline
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34861](facebook#34861))
* The bridge event types should only be defined in one direction
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34859](facebook#34859))
* Attempt at a better "unique suspender" text
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34854](facebook#34854))
* Track whether a boundary is currently suspended and make transparent
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34853](facebook#34853))
* Don't hide overflow rectangles
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34852](facebook#34852))
* Measure text nodes ([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34851](facebook#34851))
* Don't measure fallbacks when suspended
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34850](facebook#34850))
* Filter out built-in stack frames
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34828](facebook#34828))
* Exclude Suspense boundaries in hidden Activity
([eps1lon](https://github.com/eps1lon) in
[facebook#34756](facebook#34756))
* Group consecutive suspended by rows by the same name
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34830](facebook#34830))
* Preserve the original index when sorting suspended by
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34829](facebook#34829))
* Don't show the root as being non-compliant
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34827](facebook#34827))
* Ignore suspense boundaries, without visual representation, in the
timeline ([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34824](facebook#34824))
* Explicitly say which id to scroll to and only once
([sebmarkbage](https://github.com/sebmarkbage) in
[facebook#34823](facebook#34823))
* devtools: fix ellipsis truncation for key values
([sophiebits](https://github.com/sophiebits) in
[facebook#34796](facebook#34796))
* fix(devtools): remove duplicated "Display density" field in General
settings ([Anatole-Godard](https://github.com/Anatole-Godard) in
[facebook#34792](facebook#34792))
* Gate SuspenseTab ([hoxyq](https://github.com/hoxyq) in
[facebook#34754](facebook#34754))
* Release `<ViewTransition />` to Canary
([eps1lon](https://github.com/eps1lon) in
[facebook#34712](facebook#34712))

DiffTrain build for [3cde211](facebook@3cde211)
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@sebmarkbage @eps1lon