Problem: diff: using diff anchors with hidden buffers fails silently
Solution: Give specific error message for diff anchors when using hidden
buffers (Yee Cheng Chin).
Diff anchors currently will fail to parse if a buffer used for diff'ing
is hidden. Previously it would just fail as the code assumes it would
not happen normally, but this is actually possible to do if `closeoff`
and `hideoff` are not set in diffopt. Git's default diff tool "vimdiff3"
also takes advantage of this.
This fix this properly would require the `{address}` parser to be
smarter about whether a particular address relies on window position or
not (e.g. the `'.` address requires an active window, but `'a` or `1234`
do not). Since hidden diff buffers seem relatively niche, just provide a
better error message / documentation for now. This could be improved
later if there's a demand for it.
related: vim/vim#17615closes: vim/vim#17904cad3b2421d
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: Crash when using inline diff mode
(Ilya Grigoriev)
Solution: Set tp_diffbuf to NULL when skipping a diff block
(Yee Cheng Chin).
Fix an array out of bounds crash when using diffopt+=inline:char when 4
or more buffers are being diff'ed. This happens when one of the blocks
is empty. The inline highlight logic skips using that buffer's block,
but when another buffer is used later and calls diff_read() to merge the
diff blocks together, it could erroneously consider the empty block's
diff info which has not been initialized, leaving to diff numbers that
are invalid. Later on the diff num is used without bounds checking which
leads to the crash.
Fix this by making sure to unset tp_diffbuf to NULL when we skip a
block, so diff_read() will not consider this buffer to be used within
inline diff. Also, add more bounds checking just to be safe.
closes: vim/vim#17805c8b99e2d13
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: not possible to anchor specific lines in diff mode
Solution: Add support for the anchoring lines in diff mode using the
'diffanchor' option (Yee Cheng Chin).
Adds support for anchoring specific lines to each other while viewing a
diff. While lines are anchored, they are guaranteed to be aligned to
each other in a diff view, allowing the user to control and inform the
diff algorithm what the desired alignment is. Internally, this is done
by splitting up the buffer at each anchor and run the diff algorithm on
each split section separately, and then merge the results back for a
logically consistent diff result.
To do this, add a new "diffanchors" option that takes a list of
`{address}`, and a new "diffopt" option value "anchor". Each address
specified will be an anchor, and the user can choose to use any type of
address, including marks, line numbers, or pattern search. Anchors are
sorted by line number in each file, and it's possible to have multiple
anchors on the same line (this is useful when doing multi-buffer diff).
Update documentation to provide examples.
This is similar to Git diff's `--anchored` flag. Other diff tools like
Meld/Araxis Merge also have similar features (called "synchronization
points" or "synchronization links"). We are not using Git/Xdiff's
`--anchored` implementation here because it has a very limited API
(it requires usage of the Patience algorithm, and can only anchor
unique lines that are the same across both files).
Because the user could anchor anywhere, diff anchors could result in
adjacent diff blocks (one block is directly touching another without a
gap), if there is a change right above the anchor point. We don't want
to merge these diff blocks because we want to line up the change at the
anchor. Adjacent diff blocks were first allowed when linematch was
added, but the existing code had a lot of branched paths where
line-matched diff blocks were handled differently. As a part of this
change, refactor them to have a more unified code path that is
generalized enough to handle adjacent diff blocks correctly and without
needing to carve in exceptions all over the place.
closes: vim/vim#176150d9160e11c
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: inconsistent range arg for :diffget/diffput
Solution: fix the range specification, place the cursor for :diffput and
:diffget consistently on the last line (Yee Cheng Chin)
Previously, `:<range>diffget` only allowed using 1 or above in the range
value, making it impossible to use the command for a diff block at the
beginning of the file. Fix the range specification so the user can now
use 0 to specify the space before the first line. This allows
`:0,$+1diffget` to work to retrieve all the changes from the other file
instead of missing the first diff block. Also do this for `:diffput`.
Also, make `:diffput` work more similar to `:diffget`. Make it so that
if the cursor is on the last line and a new line is inserted in the
other file, doing `:diffput` will select that diff block below the line,
just like `:diffget` would.
Also clean up the logic a little bit for edge cases and for handling
line matched diff blocks better.
closes: vim/vim#17579d75ab0cbf5
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: tests: Test_diff_fold_redraw() is insufficient
(after v9.1.1439, Christ van Willegen)
Solution: improve the test (Gary Johnson)
The original Test_diff_fold_redraw() function, added 2025-06-08 at patch
9.1.1439, had a bug and didn't do a very good job of testing the fold
behavior. This new version is simpler and more thorough.
The bug was that it checked the fold state of one window twice instead
of checking both windows.
closes: vim/vim#1749269565e3618
Co-authored-by: Gary Johnson <garyjohn@spocom.com>
Problem: Last diff folds not merged (after v8.1.1922)
Solution: loop over all windows in the current tabpage and update all
folds (Gary Johnson)
This commit fixes a bug where the last two folds of a diff are not
merged when the last difference between the two diff'd buffers is
resolved.
Normally, when two buffers are diff'd, folding is used to show only the
text that differs and to hide the text that is the same between the two
buffers. When a difference is resolved by making a block of text the
same in both buffers, the folds are updated to merge that block with the
folds above and below it into one closed fold.
That updating of the folds did not occur when the block of text was the
last diff block in the buffers.
The bug was introduced by this patch on August 24, 2019:
patch 8.1.1922: in diff mode global operations can be very slow
Problem: In diff mode global operations can be very slow.
Solution: Do not call diff_redraw() many times, call it once when
redrawing. And also don't update folds multiple times.
Unfortunately, folds were then not updated often enough.
The problem was fixed by adding a short loop to the ex_diffgetput()
function in diff.c to update all the folds in the current tab when the
last difference is removed.
A test for this was added to test_diffmode.vim. Two of the reference
screen dumps for another test in that file,
Test_diffget_diffput_linematch(), had to be changed to have all the
folds closed rather than to have the last diff block remain open.
closes: vim/vim#174573fa0d3514b
Co-authored-by: Gary Johnson <garyjohn@spocom.com>
Problem: inline word diff treats multibyte chars as word char
(after 9.1.1243)
Solution: treat all non-alphanumeric characters as non-word characters
(Yee Cheng Chin)
Previously inline word diff simply used Vim's definition of keyword to
determine what is a word, which leads to multi-byte character classes
such as emojis and CJK (Chinese/Japanese/Korean) characters all
classifying as word characters, leading to entire sentences being
grouped as a single word which does not provide meaningful information
in a diff highlight.
Fix this by treating all non-alphanumeric characters (with class number
above 2) as non-word characters, as there is usually no benefit in using
word diff on them. These include CJK characters, emojis, and also
subscript/superscript numbers. Meanwhile, multi-byte characters like
Cyrillic and Greek letters will still continue to considered as words.
Note that this is slightly inconsistent with how words are defined
elsewhere, as Vim usually considers any character with class >=2 to be
a "word".
related: vim/vim#16881 (diff inline highlight)
closes: vim/vim#170509aa120f7ad
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: Typos in code and docs related to 'diffopt' "inline:".
(after v9.1.1243)
Solution: Fix typos and slightly improve the docs.
(zeertzjq)
closes: vim/vim#169975a307c361c
Problem: Diff mode's inline highlighting is lackluster. It only
performs a line-by-line comparison, and calculates a single
shortest range within a line that could encompass all the
changes. In lines with multiple changes, or those that span
multiple lines, this approach tends to end up highlighting
much more than necessary.
Solution: Implement new inline highlighting modes by doing per-character
or per-word diff within the diff block, and highlight only the
relevant parts, add "inline:simple" to the defaults (which is
the old behaviour)
This change introduces a new diffopt option "inline:<type>". Setting to
"none" will disable all inline highlighting, "simple" (the default) will
use the old behavior, "char" / "word" will perform a character/word-wise
diff of the texts within each diff block and only highlight the
differences.
The new char/word inline diff only use the internal xdiff, and will
respect diff options such as algorithm choice, icase, and misc iwhite
options. indent-heuristics is always on to perform better sliding.
For character highlight, a post-process of the diff results is first
applied before we show the highlight. This is because a naive diff will
create a result with a lot of small diff chunks and gaps, due to the
repetitive nature of individual characters. The post-process is a
heuristic-based refinement that attempts to merge adjacent diff blocks
if they are separated by a short gap (1-3 characters), and can be
further tuned in the future for better results. This process results in
more characters than necessary being highlighted but overall less visual
noise.
For word highlight, always use first buffer's iskeyword definition.
Otherwise if each buffer has different iskeyword settings we would not
be able to group words properly.
The char/word diffing is always per-diff block, not per line, meaning
that changes that span multiple lines will show up correctly.
Added/removed newlines are not shown by default, but if the user has
'list' set (with "eol" listchar defined), the eol character will be be
highlighted correctly for the specific newline characters.
Also, add a new "DiffTextAdd" highlight group linked to "DiffText" by
default. It allows color schemes to use different colors for texts that
have been added within a line versus modified.
This doesn't interact with linematch perfectly currently. The linematch
feature splits up diff blocks into multiple smaller blocks for better
visual matching, which makes inline highlight less useful especially for
multi-line change (e.g. a line is broken into two lines). This could be
addressed in the future.
As a side change, this also removes the bounds checking introduced to
diff_read() as they were added to mask existing logic bugs that were
properly fixed in vim/vim#16768.
closes: vim/vim#168819943d4790e
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: Vim's diff block merging algorithm when doing a multi-file diff
is buggy when two different diff hunks overlap a single
existing diff block (after v9.1.0743)
Solution: fix a couple bugs in this logic:
1. Fix regression from v9.1.0743 where it's not correctly expanding the
2nd overlap correctly, where it always expands without taking into
account that this was always taken care of when the first overlap
happened. Instead, we should only grow the 2nd overlap if it overhangs
outside the existing diff block, and if we encounter a new overlapping
diff block (due to overlap chaining).
2. When we expand a diff block to match the hunk size on the orig side
(when handling the first overlap), we expand the same amount of lines
in the new side. This is not sound if there exists a second overlap
hunk that we haven't processed yet, and that hunk has different
number of lines in orig/new. Fix this by doing the corresponding
counter adjustment when handling 2nd/3rd/etc overlap by calculating
the difference in lines between orig and new side.
(Yee Cheng Chin)
closes: vim/vim#16768bc08ceb755
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
Problem: no sanitize check when running linematch
Solution: add sanitize check before applying the linematch algorithm,
similar to diff_find_change() (Jonathon)
closes: vim/vim#16446ca307efe48
Co-authored-by: Jonathon <jonathonwhite@protonmail.com>
Problem: topline might be changed in diff mode unexpectedly
(Jaehwang Jung)
Solution: do not re-calculate topline, when using line() func
in diff mode.
fixes: vim/vim#15812closes: vim/vim#1595005a40e07c2
Co-authored-by: Christian Brabandt <cb@256bit.org>
Problem: diff mode does not handle overlapping diffs correctly
Solution: correct the logic to handle overlapping blocks
(Yukihiro Nakadaira)
Vim merges overlapped diff blocks and it doesn't work expectedly
in some situation.
closes: vim/vim#1573506fe70c183
Co-authored-by: Yukihiro Nakadaira <yukihiro.nakadaira@gmail.com>
Problem: incorrect internal diff with an empty file
Solution: Set pointer to NULL, instead of using an empty line file
(Yukihiro Nakadaira)
When using internal diff, empty file is read as one empty line file.
So result differs from external diff.
closes: vim/vim#15719f1694b439b
Co-authored-by: Yukihiro Nakadaira <yukihiro.nakadaira@gmail.com>
Problem: Code style is not check in test scripts.
Solution: Add basic code style check for test files.
94722c5107
Use Test_test_files() from latest Vim.
Co-authored-by: Bram Moolenaar <Bram@vim.org>
Problem: plines_m_win() does not take into account it's "limit_winheight"
argument for filler lines below the last line of the buffer.
(after v9.1.0280)
Solution: Check window height when "limit_winheight" is TRUE.
(Luuk van Baal)
08b0f632c1
Problem: Wrong doc style for pandoc syntax description,
Test_diff_eob_halfpage() may fail depending on
screen size, using braces in highlight.c when
not necessary
Solution: Fix pandoc documentation, make sure the window
for the test has 7 lines, remove the braces.
a040019be6
Co-authored-by: Christian Brabandt <cb@256bit.org>
Problem: Logic to make sure cursor is in visible part of the screen after
scrolling the text with 'smoothscroll' is scattered, asymmetric
and contains bugs.
Solution: Adjust and create helper function for 'smoothscroll' cursor logic.
(Luuk van Baal)
9148ba8a46
Problem: Support for 'smoothscroll' in (half-)page scrolling
broke backward compatibility and can be made to work better.
(after v9.1.215)
Solution: Restore the previous cursor and end-of-buffer behavior for
half-page scrolling and improve 'smoothscroll' support.
(Luuk van Baal)
cb204e688e
Problem: Page-wise scrolling with Ctrl-F/Ctrl-B implements
it's own logic to change the topline and cursor.
In doing so, skipcol is not handled properly for
'smoothscroll', and virtual lines.
Solution: Re-use the logic from Ctrl-E/Ctrl-Y while staying
backward compatible as much as possible.
b9f5b95b7b
Problem: Wrong display or screenpos() result when toggling diff mode.
Solution: Reset w_skipcol when disabling 'wrap'. Reset w_leftcol when
enabling 'wrap' (zeertzjq).
fixes: vim/vim#14210closes: vim/vim#142119e7f1fc2f1
Problem: 'breakindentopt' "min" works incorrectly with 'signcolumn'.
Solution: Use win_col_off() and win_col_off2().
(zeertzjq)
closes: vim/vim#14014f0a9d65e0a
Problem: 'breakindent' is not drawn after diff filler lines.
Solution: Correct check for whether 'breakindent' should be drawn.
closes: vim/vim#13624588f20dece
Cherry-pick Test_diff_with_syntax() change from patch 9.0.1257.
Problem: Tests are flaky because of using a common file name.
Solution: Rename files and directories to be more unique.
61abe7d8f8
Cherry-pick Test_custom_complete_autoload() from patch 8.2.4584.
Cherry-pick test_delete.vim & test_edit.vim changes from patch 9.0.0323.
Cherry-pick test_edit.vim changes from patch 8.2.3637.
Co-authored-by: Bram Moolenaar <Bram@vim.org>
Problem: Cannot scroll up in diff mode with many filler lines and zero
'scrolloff'.
Solution: Invalidate w_cline_row before calling comp_botline().
closes: vim/vim#132560583491277
Problem: CTRL-A does not work properly with the cmdline popup menu.
Solution: Fix issues with CTRL-A. Add more tests for the cmdline popup
menu. Remove TermWait() before VeriryScreenDump(). Refactor the
cmdline popup code. (Yegappan Lakshmanan, closesvim/vim#9735)
560dff49c0
Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Problem: Test_xrestore sometimes fails.
Solution: Mark the test as flayky. Move marking test as flaky to the test
instead of listing them in runtest.
f08b0eb869
Co-authored-by: Bram Moolenaar <Bram@vim.org>
Problem: Scrolling too many lines when 'wrap' and 'diff' are set.
Solution: Only scroll by screenlines for 'diff' when 'wrap' is not set.
(closesvim/vim#12211)
38d867f041
Co-authored-by: Bram Moolenaar <Bram@vim.org>
