fix: prevent race conditions when applying multiple diffs in parallel

[uinstinct]

Description

Wait for the previous edit tool to create its diff in the IDE before the next edit tool.
This caused race conditions because the code required the text editor to be active for the diff to be streamed into the proper file.

resolves CON-5048

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• [] The relevant tests, if any, have been updated or created

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Summary by cubic

Prevent race conditions when multiple edit tools apply diffs at the same time by targeting the correct file editor. Each diff now streams to the right file without relying on the active editor.

• Bug Fixes
  • Require filepath in ApplyToFilePayload.
  • Open and use the specific editor via openEditorAndRevealRange; stop relying on activeTextEditor.
  • Pass filepath through instantApplyDiff to apply diffs to the correct file (CON-5048).

^{Written for commit 4d4211f. Summary will update on new commits.}

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[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="gui/src/redux/thunks/handleApplyStateUpdate.ts">

<violation number="1" location="gui/src/redux/thunks/handleApplyStateUpdate.ts:172">
P1: Concurrent apply thunks can deadlock: the wait loop counts the current not-started apply state, so two simultaneous calls both wait forever and never call applyToFile.</violation>
</file>

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[RomneyDa]

Is there a more deterministic approach we could take to queuing these diffs?

My concern is that 1000 ms is kind of long so in the case a diff stopped streaming just after it checks (1000 ms till next check) and then someone starts clicking around it would suddenly start streaming and feel glitchy?

[uinstinct]

Is there a more deterministic approach we could take to queuing these diffs?

My concern is that 1000 ms is kind of long so in the case a diff stopped streaming just after it checks (1000 ms till next check) and then someone starts clicking around it would suddenly start streaming and feel glitchy?

True. It need not be 1000 ms. I added that as an approximate - but most diffs resolve faster. Will put 100 ms instead.

[RomneyDa]

@uinstinct I think we should consider more predictable routes to applying the diffs in order, there are other issues with this approach e.g. selectApplyStatesInProgress could potentially detect some stale apply states which were ignored in a previous session etc and then it would never apply the diff

Let's avoid polling if possible and implement some kind of predictable queue.

[uinstinct]

@uinstinct I think we should consider more predictable routes to applying the diffs in order, there are other issues with this approach e.g. selectApplyStatesInProgress could potentially detect some stale apply states which were ignored in a previous session etc and then it would never apply the diff

Let's avoid polling if possible and implement some kind of predictable queue.

implemented a new method to rely on getting the filepath's editor without opening activeTextEditor

[cubic-dev-ai]

1 issue found across 5 files (changes from recent commits).

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="extensions/vscode/src/diff/vertical/manager.ts">

<violation number="1" location="extensions/vscode/src/diff/vertical/manager.ts:308">
P2: instantApplyDiff now assumes `filepath` is already a URI string; passing a filesystem path breaks handler creation and map lookups because `Uri.parse` and `fileUriToCodeLens` keys won’t match the editor’s file:// URI.</violation>
</file>

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