## Problem
Repeatedly toggling `=` in fugitive left green gutter
(`number_hl_group`)
extmarks on lines between sections. When fugitive collapses a diff
section,
Neovim compresses extmarks from deleted lines onto the next surviving
line
(the `M ...` file entry). Two issues prevented cleanup:
1. `carry_forward_highlighted` returned `{}` (truthy in Lua) when zero
hunks
matched, so `pending_clear` stayed `false` and the compressed extmarks
were never cleared.
2. The `nvim_buf_clear_namespace` call in `on_buf`'s `pending_clear`
path was
removed in 2feb8a8, so even when `pending_clear` was `true` the extmarks
survived.
## Solution
Return `nil` from `carry_forward_highlighted` when no hunks were carried
forward (`next(highlighted) == nil`), so `pending_clear` is correctly
set to
`true`. Restore `nvim_buf_clear_namespace` in `on_buf`'s `pending_clear`
block. Add `process_pending_clear` test helper and spec coverage.
## Problem
Toggling large diffs via fugitive's `=` caused the top of the buffer to
re-render and glitch. `ensure_cache` always created a new cache entry
with
`pending_clear=true` and `highlighted={}`, forcing `on_win` to clear and
re-highlight every visible hunk — including stable ones above the toggle
point that never changed.
## Solution
On reparse, compare old and new hunk lists using a prefix + suffix
matching
strategy. Hunks that match (same filename, line count, and sampled
content)
carry forward their `highlighted` state so `on_win` skips them.
Comparison
is O(1) per hunk. Only runs when the old entry had
`pending_clear=false`;
`invalidate_cache`/`ColorScheme` paths still force full re-highlight.
Closes#131
## Problem
Regressions #119 and #120 showed the test suite had no coverage of the
decoration provider cache pipeline, no end-to-end pipeline tests from
buffer content to extmarks, and no Neogit-specific integration tests.
## Solution
Adds three new spec files (28 new tests, 316 total):
- `spec/decoration_provider_spec.lua` — indirect cache pipeline tests
via `_test` table: `ensure_cache` population, content fingerprint guard,
`pending_clear` semantics, BufWipeout cleanup
- `spec/integration_spec.lua` — full pipeline: diff buffer → `attach` →
extmarks; verifies `DiffsAdd`/`DiffsDelete` on correct lines, treesitter
captures, multi-hunk coverage
- `spec/neogit_integration_spec.lua` — `neogit_disable_hunk_highlight`
behavior, NeogitStatus/NeogitDiffView attach and cache population,
parser neogit filename patterns
Depends on #133.
Closes#122
