* feat(vcs): IDEA's diff algorithm and change colouring in the diff viewer
Port IntelliJ's text comparison to TypeScript (src/features/vcs/comparison):
Myers/patience LCS with unique-element discarding, ByLine (smart matching
that skips unimportant lines, chunk optimizer, second-step correction),
ByWord (word chunks, punctuation matching, whitespace policies, line block
splitting) and ComparisonManager's compareLinesInner / processBlocks. The
port runs IntelliJ's own LineComparisonUtilTest, WordComparisonUtilTest and
SplitComparisonUtilTest cases (459 runs), converted to ideaCases.json.
MergeView chunks now come straight from these line fragments, with the
inner word fragments as chunk changes, instead of @codemirror/merge's
presentable diff. Revert and >> / << replace lines as
DiffUtil.applyModification does.
Colour changes as IDEA does: modified (blue), inserted (green) and deleted
(grey) by chunk type, a lighter line background for chunks whose words were
compared, each word fragment in its own type at full line height, a thin
bar for a fragment empty on one side, and the colours carried into the
gutters and the divider bands. New --diff-modified / --diff-inserted /
--diff-deleted theme tokens, imported from .icls DIFF_* attributes.
Add a Playwright suite over a generated git repository of diff cases,
including 10,000-line files, in every viewer mode.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
* fix(vcs): preserve unified revert boundaries and bound large diffs
---------
Co-authored-by: Claude Opus 5.5 <[email protected]>
Co-authored-by: l0ng-ai <[email protected]>
The side-by-side diff gets two independent options. Synchronize Scrolling (toolbar lock, also in the settings menu, on by default) scrolls both panes together; Align Changes (settings menu, off by default) pads the panes so changes line up. With Align Changes off, the panes keep their own heights and a divider of curved bands joins each change, with arrows to apply it; scrolling one pane moves the other through the matching change (anchored at a third of the height), including caret moves and the wheel over the divider. Scroll mapping and the divider look up changes by binary search, so large files with thousands of changes scroll smoothly.
Claude-Session: https://claude.ai/code/session_01Dq6jQQn8ZhRfkkyj3PRutA
Co-authored-by: jaw52 <[email protected]>
Read-only revision panes inherited the workbench's user-select: none and had no tab stop, so text couldn't be selected with the mouse or keyboard or copied. The viewer content now allows text selection and read-only panes take focus; editing stays blocked.
Once focusable, these panes picked up CodeMirror's dark-theme focused selection colour, which outranked the viewer's rule and made selected text unreadable in light themes; the viewer's selection rule now matches that specificity.
Co-authored-by: dvictor357 <[email protected]>
In long files several distant edits could collapse into one large replacement that highlighted unchanged lines, and multi-line changes showed per-line stripes.
Lines are now matched before character-level changes. The line diff is anchored on lines that occur once on both sides (patience-style), with a bounded diff only between anchors, so 50k-line files with distant edits keep separate chunks. Whole inserted or deleted lines render as continuous blocks; paired modified lines keep the line background plus word-level highlights, also inside multi-line chunks. Line decorations are built for the visible range only.
Co-authored-by: zzxzz12345 <[email protected]>
Claude-Session: https://claude.ai/code/session_01VUYsdXA2nkF5v6zsC93dpn
Dimas Victorтаdvictor357
胡翀таzzxzz12345