Graph - fix case when the merge base is not yet fetched #275145
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Pull Request Overview
This PR adds defensive checks to prevent array index access errors when creating incoming/outgoing changes nodes in the SCM history graph. The changes guard against scenarios where the merge base history item might not be loaded yet.
Key changes:
- Added validation to check that both
beforeHistoryItemIndexandafterHistoryItemIndexare valid (-1 check) before accessing array elements - Updated comments to clarify that indices might not be found if history items are not yet loaded
- Wrapped the incoming and outgoing changes node creation logic in conditional blocks
| // Create incoming changes node | ||
| const inputSwimlanes = viewModels[beforeHistoryItemIndex].outputSwimlanes.map(i => deepClone(i)); | ||
| const outputSwimlanes = viewModels[afterHistoryItemIndex].inputSwimlanes.map(i => deepClone(i)); | ||
| const displayIdLength = viewModels[0].historyItem.displayId?.length ?? 0; |
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Potential array access error: viewModels[0] can throw if the array is empty. Although the function builds viewModels from historyItems, this code is inside a guard that only checks beforeHistoryItemIndex !== -1 && afterHistoryItemIndex !== -1, which doesn't guarantee the array is non-empty. Consider adding a check viewModels.length > 0 or using optional chaining: viewModels[0]?.historyItem.displayId?.length ?? 0.
| const displayIdLength = viewModels[0].historyItem.displayId?.length ?? 0; | |
| const displayIdLength = viewModels[0]?.historyItem.displayId?.length ?? 0; |
| }) | ||
| : []; | ||
| const outputSwimlanes = viewModels[afterHistoryItemIndex].inputSwimlanes.slice(0); | ||
| const displayIdLength = viewModels[0].historyItem.displayId?.length ?? 0; |
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Potential array access error: viewModels[0] can throw if the array is empty. Although the function builds viewModels from historyItems, this code is inside a guard that only checks afterHistoryItemIndex !== -1, which doesn't guarantee the array is non-empty. Consider adding a check viewModels.length > 0 or using optional chaining: viewModels[0]?.historyItem.displayId?.length ?? 0.
| const displayIdLength = viewModels[0].historyItem.displayId?.length ?? 0; | |
| const displayIdLength = viewModels[0]?.historyItem.displayId?.length ?? 0; |
Fixes #275089