barrett/diffs.nvim
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 13
diffs.nvim/spec/parser_spec.lua
Barrett Ruth cc5a368838
Some checks are pending
luarocks / quality (push) Waiting to run
Details
luarocks / publish (push) Blocked by required conditions
Details
fix(highlight): support combined diff format for unmerged files (#106) 
## Problem

Fugitive shows combined diffs (`@@@` headers, 2-character prefixes like
`++`, ` +`, `+ `) for unmerged (`UU`) files. The parser and highlight
pipeline assumed unified diff format (`@@`, 1-char prefix), causing:

- Prefix concealment only hiding 1 of 2 prefix chars
- Missing background colors on ` +` and `+ ` lines (first char is space
→ misclassified as context)
- No treesitter highlights (extra prefix char poisoned code arrays)
- `U` file header not recognized by parser (missing from filename
pattern)

## Solution

Detect prefix width from leading `@` count in hunk headers (`@@` → 1,
`@@@` → 2). Propagate `prefix_width` through the pipeline:

- **Parser**: new `prefix_width` field on `diffs.Hunk`, `U` added to
filename pattern, combined diff range extraction
- **Highlight**: prefix stripping, `col_offset`, concealment width, and
line classification all use `prefix_width`
- **Intra-line**: skipped for combined diffs (`prefix_width > 1`) since
2-char prefix semantics don't produce meaningful change groups
2026-02-09 19:30:13 -05:00

561 lines
16 KiB
Lua
Raw Permalink Blame History

require('spec.helpers')
local parser = require('diffs.parser')
describe('parser', function()
describe('parse_buffer', function()
local function create_buffer(lines)
local bufnr = vim.api.nvim_create_buf(false, true)
vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
return bufnr
end
local function delete_buffer(bufnr)
if vim.api.nvim_buf_is_valid(bufnr) then
vim.api.nvim_buf_delete(bufnr, { force = true })
end
end
it('returns empty table for empty buffer', function()
local bufnr = create_buffer({})
local hunks = parser.parse_buffer(bufnr)
assert.are.same({}, hunks)
delete_buffer(bufnr)
end)
it('returns empty table for buffer with no hunks', function()
local bufnr = create_buffer({
'Head: main',
'Help: g?',
'',
'Unstaged (1)',
'M lua/test.lua',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.same({}, hunks)
delete_buffer(bufnr)
end)
it('detects single hunk with lua file', function()
local bufnr = create_buffer({
'Unstaged (1)',
'M lua/test.lua',
'@@ -1,3 +1,4 @@',
' local M = {}',
'+local new = true',
' return M',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('lua/test.lua', hunks[1].filename)
assert.are.equal('lua', hunks[1].ft)
assert.are.equal('lua', hunks[1].lang)
assert.are.equal(3, hunks[1].start_line)
assert.are.equal(3, #hunks[1].lines)
delete_buffer(bufnr)
end)
it('detects multiple hunks in same file', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -1,2 +1,2 @@',
' local M = {}',
'-local old = false',
'+local new = true',
'@@ -10,2 +10,3 @@',
' function M.foo()',
'+ print("hello")',
' end',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(2, #hunks)
assert.are.equal(2, hunks[1].start_line)
assert.are.equal(6, hunks[2].start_line)
delete_buffer(bufnr)
end)
it('detects hunks across multiple files', function()
local orig_get_lang = vim.treesitter.language.get_lang
local orig_inspect = vim.treesitter.language.inspect
vim.treesitter.language.get_lang = function(ft)
local result = orig_get_lang(ft)
if result then
return result
end
if ft == 'python' then
return 'python'
end
return nil
end
vim.treesitter.language.inspect = function(lang)
if lang == 'python' then
return {}
end
return orig_inspect(lang)
end
local bufnr = create_buffer({
'M lua/foo.lua',
'@@ -1,1 +1,2 @@',
' local M = {}',
'+local x = 1',
'M src/bar.py',
'@@ -1,1 +1,2 @@',
' def hello():',
'+ pass',
})
local hunks = parser.parse_buffer(bufnr)
vim.treesitter.language.get_lang = orig_get_lang
vim.treesitter.language.inspect = orig_inspect
assert.are.equal(2, #hunks)
assert.are.equal('lua/foo.lua', hunks[1].filename)
assert.are.equal('lua', hunks[1].lang)
assert.are.equal('src/bar.py', hunks[2].filename)
assert.are.equal('python', hunks[2].lang)
delete_buffer(bufnr)
end)
it('extracts header context', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -10,3 +10,4 @@ function M.hello()',
' local msg = "hi"',
'+print(msg)',
' end',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('function M.hello()', hunks[1].header_context)
assert.is_not_nil(hunks[1].header_context_col)
delete_buffer(bufnr)
end)
it('handles header without context', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -1,2 +1,3 @@',
' local M = {}',
'+local x = 1',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.is_nil(hunks[1].header_context)
delete_buffer(bufnr)
end)
it('handles all git status prefixes', function()
local prefixes = { 'M', 'A', 'D', 'R', 'C', '?', '!' }
for _, prefix in ipairs(prefixes) do
local bufnr = create_buffer({
prefix .. ' test.lua',
'@@ -1,1 +1,2 @@',
' local x = 1',
'+local y = 2',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks, 'Failed for prefix: ' .. prefix)
delete_buffer(bufnr)
end
end)
it('stops hunk at blank line', function()
local bufnr = create_buffer({
'M test.lua',
'@@ -1,2 +1,3 @@',
' local x = 1',
'+local y = 2',
'',
'Some other content',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(2, #hunks[1].lines)
delete_buffer(bufnr)
end)
it('emits hunk with ft when no ts parser available', function()
local bufnr = create_buffer({
'M test.xyz_no_parser',
'@@ -1,1 +1,2 @@',
' some content',
'+more content',
})
vim.filetype.add({ extension = { xyz_no_parser = 'xyz_no_parser_ft' } })
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('xyz_no_parser_ft', hunks[1].ft)
assert.is_nil(hunks[1].lang)
assert.are.equal(2, #hunks[1].lines)
delete_buffer(bufnr)
end)
it('stops hunk at next file header', function()
local bufnr = create_buffer({
'M test.lua',
'@@ -1,2 +1,3 @@',
' local x = 1',
'+local y = 2',
'M other.lua',
'@@ -1,1 +1,1 @@',
' local z = 3',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(2, #hunks)
assert.are.equal(2, #hunks[1].lines)
assert.are.equal(1, #hunks[2].lines)
delete_buffer(bufnr)
end)
it('attaches header_lines to first hunk only', function()
local bufnr = create_buffer({
'diff --git a/parser.lua b/parser.lua',
'index 3e8afa0..018159c 100644',
'--- a/parser.lua',
'+++ b/parser.lua',
'@@ -1,2 +1,3 @@',
' local M = {}',
'+local x = 1',
'@@ -10,2 +11,3 @@',
' function M.foo()',
'+ return true',
' end',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(2, #hunks)
assert.is_not_nil(hunks[1].header_start_line)
assert.is_not_nil(hunks[1].header_lines)
assert.are.equal(1, hunks[1].header_start_line)
assert.is_nil(hunks[2].header_start_line)
assert.is_nil(hunks[2].header_lines)
delete_buffer(bufnr)
end)
it('header_lines contains only diff metadata, not hunk content', function()
local bufnr = create_buffer({
'diff --git a/parser.lua b/parser.lua',
'index 3e8afa0..018159c 100644',
'--- a/parser.lua',
'+++ b/parser.lua',
'@@ -1,2 +1,3 @@',
' local M = {}',
'+local x = 1',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(4, #hunks[1].header_lines)
assert.are.equal('diff --git a/parser.lua b/parser.lua', hunks[1].header_lines[1])
assert.are.equal('index 3e8afa0..018159c 100644', hunks[1].header_lines[2])
assert.are.equal('--- a/parser.lua', hunks[1].header_lines[3])
assert.are.equal('+++ b/parser.lua', hunks[1].header_lines[4])
delete_buffer(bufnr)
end)
it('handles fugitive status format with diff headers', function()
local bufnr = create_buffer({
'Head: main',
'Push: origin/main',
'',
'Unstaged (1)',
'M parser.lua',
'diff --git a/parser.lua b/parser.lua',
'index 3e8afa0..018159c 100644',
'--- a/parser.lua',
'+++ b/parser.lua',
'@@ -1,2 +1,3 @@',
' local M = {}',
'+local x = 1',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(6, hunks[1].header_start_line)
assert.are.equal(4, #hunks[1].header_lines)
assert.are.equal('diff --git a/parser.lua b/parser.lua', hunks[1].header_lines[1])
delete_buffer(bufnr)
end)
it('emits hunk for files with unknown filetype', function()
local bufnr = create_buffer({
'M config.obscuretype',
'@@ -1,2 +1,3 @@',
' setting1 = value1',
'-setting2 = value2',
'+setting2 = MODIFIED',
'+setting4 = newvalue',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('config.obscuretype', hunks[1].filename)
assert.is_nil(hunks[1].ft)
assert.is_nil(hunks[1].lang)
assert.are.equal(4, #hunks[1].lines)
delete_buffer(bufnr)
end)
it('uses filetype from existing buffer when available', function()
local repo_root = '/tmp/test-repo'
local file_path = repo_root .. '/build'
local file_buf = vim.api.nvim_create_buf(false, true)
vim.api.nvim_buf_set_name(file_buf, file_path)
vim.api.nvim_set_option_value('filetype', 'bash', { buf = file_buf })
local diff_buf = create_buffer({
'M build',
'@@ -1,2 +1,3 @@',
' echo "hello"',
'+set -e',
' echo "done"',
})
vim.api.nvim_buf_set_var(diff_buf, 'diffs_repo_root', repo_root)
local hunks = parser.parse_buffer(diff_buf)
assert.are.equal(1, #hunks)
assert.are.equal('build', hunks[1].filename)
assert.are.equal('bash', hunks[1].ft)
delete_buffer(file_buf)
delete_buffer(diff_buf)
end)
it('uses filetype from existing buffer via git_dir', function()
local git_dir = '/tmp/test-repo/.git'
local repo_root = '/tmp/test-repo'
local file_path = repo_root .. '/script'
local file_buf = vim.api.nvim_create_buf(false, true)
vim.api.nvim_buf_set_name(file_buf, file_path)
vim.api.nvim_set_option_value('filetype', 'python', { buf = file_buf })
local diff_buf = create_buffer({
'M script',
'@@ -1,2 +1,3 @@',
' def main():',
'+ print("hi")',
' pass',
})
vim.api.nvim_buf_set_var(diff_buf, 'git_dir', git_dir)
local hunks = parser.parse_buffer(diff_buf)
assert.are.equal(1, #hunks)
assert.are.equal('script', hunks[1].filename)
assert.are.equal('python', hunks[1].ft)
delete_buffer(file_buf)
delete_buffer(diff_buf)
end)
it('detects filetype from file content shebang without open buffer', function()
local repo_root = '/tmp/diffs-test-shebang'
vim.fn.mkdir(repo_root, 'p')
local file_path = repo_root .. '/build'
local f = io.open(file_path, 'w')
f:write('#!/bin/bash\n')
f:write('set -e\n')
f:write('echo "hello"\n')
f:close()
local diff_buf = create_buffer({
'M build',
'@@ -1,2 +1,3 @@',
' #!/bin/bash',
'+set -e',
' echo "hello"',
})
vim.api.nvim_buf_set_var(diff_buf, 'diffs_repo_root', repo_root)
local hunks = parser.parse_buffer(diff_buf)
assert.are.equal(1, #hunks)
assert.are.equal('build', hunks[1].filename)
assert.are.equal('sh', hunks[1].ft)
delete_buffer(diff_buf)
os.remove(file_path)
vim.fn.delete(repo_root, 'rf')
end)
it('extracts file line numbers from @@ header', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -1,3 +1,4 @@',
' local M = {}',
'+local new = true',
' return M',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(1, hunks[1].file_old_start)
assert.are.equal(3, hunks[1].file_old_count)
assert.are.equal(1, hunks[1].file_new_start)
assert.are.equal(4, hunks[1].file_new_count)
delete_buffer(bufnr)
end)
it('defaults count to 1 when omitted in @@ header', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -1 +1 @@',
' local M = {}',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(1, hunks[1].file_old_start)
assert.are.equal(1, hunks[1].file_old_count)
assert.are.equal(1, hunks[1].file_new_start)
assert.are.equal(1, hunks[1].file_new_count)
delete_buffer(bufnr)
end)
it('recognizes U prefix for unmerged files', function()
local bufnr = create_buffer({
'U merge_me.lua',
'@@@ -1,3 -1,5 +1,9 @@@',
' local M = {}',
'++<<<<<<< HEAD',
' + return 1',
'++=======',
'+ return 2',
'++>>>>>>> feature',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('merge_me.lua', hunks[1].filename)
assert.are.equal('lua', hunks[1].ft)
delete_buffer(bufnr)
end)
it('sets prefix_width 2 from @@@ combined diff header', function()
local bufnr = create_buffer({
'U test.lua',
'@@@ -1,3 -1,5 +1,9 @@@',
' local M = {}',
'++<<<<<<< HEAD',
' + return 1',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(2, hunks[1].prefix_width)
delete_buffer(bufnr)
end)
it('sets prefix_width 1 for standard @@ unified diff', function()
local bufnr = create_buffer({
'M test.lua',
'@@ -1,2 +1,3 @@',
' local x = 1',
'+local y = 2',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(1, hunks[1].prefix_width)
delete_buffer(bufnr)
end)
it('collects all combined diff line types as hunk content', function()
local bufnr = create_buffer({
'U test.lua',
'@@@ -1,3 -1,3 +1,5 @@@',
' local M = {}',
'++<<<<<<< HEAD',
' + return 1',
'+ local x = 2',
' end',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(5, #hunks[1].lines)
assert.are.equal(' local M = {}', hunks[1].lines[1])
assert.are.equal('++<<<<<<< HEAD', hunks[1].lines[2])
assert.are.equal(' + return 1', hunks[1].lines[3])
assert.are.equal('+ local x = 2', hunks[1].lines[4])
assert.are.equal(' end', hunks[1].lines[5])
delete_buffer(bufnr)
end)
it('extracts new range from combined diff header', function()
local bufnr = create_buffer({
'U test.lua',
'@@@ -1,3 -1,5 +1,9 @@@',
' local M = {}',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal(1, hunks[1].file_new_start)
assert.are.equal(9, hunks[1].file_new_count)
assert.is_nil(hunks[1].file_old_start)
delete_buffer(bufnr)
end)
it('extracts header context from combined diff header', function()
local bufnr = create_buffer({
'U test.lua',
'@@@ -1,3 -1,5 +1,9 @@@ function M.greet()',
' local M = {}',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('function M.greet()', hunks[1].header_context)
delete_buffer(bufnr)
end)
it('resets prefix_width when switching from combined to unified diff', function()
local bufnr = create_buffer({
'U merge.lua',
'@@@ -1,1 -1,1 +1,3 @@@',
' local M = {}',
'++<<<<<<< HEAD',
'M other.lua',
'@@ -1,1 +1,2 @@',
' local x = 1',
'+local y = 2',
})
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(2, #hunks)
assert.are.equal(2, hunks[1].prefix_width)
assert.are.equal(1, hunks[2].prefix_width)
delete_buffer(bufnr)
end)
it('stores repo_root on hunk when available', function()
local bufnr = create_buffer({
'M lua/test.lua',
'@@ -1,3 +1,4 @@',
' local M = {}',
'+local new = true',
' return M',
})
vim.api.nvim_buf_set_var(bufnr, 'diffs_repo_root', '/tmp/test-repo')
local hunks = parser.parse_buffer(bufnr)
assert.are.equal(1, #hunks)
assert.are.equal('/tmp/test-repo', hunks[1].repo_root)
delete_buffer(bufnr)
end)
end)
end)
Reference in a new issue View git blame Copy permalink