editor: Fix prepaint recursion when updating stale sizes #42896
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
cla-bot
bot
added
the
cla-signed
smitbarmase
changed the title
JosephTLyons
added a commit
that referenced
this pull request
Nov 19, 2025
)" This reverts commit 79be5cb.
mikayla-maki
pushed a commit
that referenced
this pull request
Nov 20, 2025
The bug is in the `place_near` logic, specifically the `!row_block_types.contains_key(&(row - 1))` check. The problem isn’t really that condition itself, but it’s that it relies on `row_block_types`, which does not take into account that upon block resizes, subsequent block start row moves up/down. Since `place_near` depends on this incorrect map, it ends up causing incorrect resize syncs to the block map, which then triggers more bad recursive calls. The reason it worked till now in most of the cases is that recursive resizes eventually lead to stabilizing it. Before `place_near`, we never touched `row_block_types` during the first prepaint pass because we knew it was based on outdated heights. Once all heights are finalized, using it is fine. The fix is to make sure `row_block_types` is accurate from the very first prepaint pass by keeping an offset whenever a block shrinks or expands. Now ideally it should take only one subsequent prepaint. But due to shrinking, new custom/diagnostics blocks might come into the view from below, which needs further prepaint calls for resolving. Right now, tests pass after 2 subsequent prepaint calls. Just to be safe, we have set it to 5. <img width="500" alt="image" src="https://github.com/user-attachments/assets/da3d32ff-5972-46d9-8597-b438e162552b" /> Release Notes: - Fix issue where sometimes Zed used to experience freeze while working with inline diagnostics.
11happy
pushed a commit
to 11happy/zed
that referenced
this pull request
Dec 1, 2025
…ies#42896) The bug is in the `place_near` logic, specifically the `!row_block_types.contains_key(&(row - 1))` check. The problem isn’t really that condition itself, but it’s that it relies on `row_block_types`, which does not take into account that upon block resizes, subsequent block start row moves up/down. Since `place_near` depends on this incorrect map, it ends up causing incorrect resize syncs to the block map, which then triggers more bad recursive calls. The reason it worked till now in most of the cases is that recursive resizes eventually lead to stabilizing it. Before `place_near`, we never touched `row_block_types` during the first prepaint pass because we knew it was based on outdated heights. Once all heights are finalized, using it is fine. The fix is to make sure `row_block_types` is accurate from the very first prepaint pass by keeping an offset whenever a block shrinks or expands. Now ideally it should take only one subsequent prepaint. But due to shrinking, new custom/diagnostics blocks might come into the view from below, which needs further prepaint calls for resolving. Right now, tests pass after 2 subsequent prepaint calls. Just to be safe, we have set it to 5. <img width="500" alt="image" src="https://github.com/user-attachments/assets/da3d32ff-5972-46d9-8597-b438e162552b" /> Release Notes: - Fix issue where sometimes Zed used to experience freeze while working with inline diagnostics.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The bug is in the
place_nearlogic, specifically the!row_block_types.contains_key(&(row - 1))check. The problem isn’t really that condition itself, but it’s that it relies onrow_block_types, which does not take into account that upon block resizes, subsequent block start row moves up/down. Sinceplace_neardepends on this incorrect map, it ends up causing incorrect resize syncs to the block map, which then triggers more bad recursive calls. The reason it worked till now in most of the cases is that recursive resizes eventually lead to stabilizing it.Before
place_near, we never touchedrow_block_typesduring the first prepaint pass because we knew it was based on outdated heights. Once all heights are finalized, using it is fine.The fix is to make sure
row_block_typesis accurate from the very first prepaint pass by keeping an offset whenever a block shrinks or expands. Now ideally it should take only one subsequent prepaint. But due to shrinking, new custom/diagnostics blocks might come into the view from below, which needs further prepaint calls for resolving. Right now, tests pass after 2 subsequent prepaint calls. Just to be safe, we have set it to 5.Release Notes: