vimrc/sources_non_forked/vim-gitgutter/autoload/gitgutter/diff.vim
2018-02-04 12:35:08 +01:00

348 lines
12 KiB
VimL

if exists('g:gitgutter_grep_command')
let s:grep_available = 1
let s:grep_command = g:gitgutter_grep_command
else
let s:grep_available = executable('grep')
if s:grep_available
let s:grep_command = 'grep'
if $GREP_OPTIONS =~# '--color=always'
let s:grep_command .= ' --color=never'
endif
endif
endif
let s:hunk_re = '^@@ -\(\d\+\),\?\(\d*\) +\(\d\+\),\?\(\d*\) @@'
let s:c_flag = gitgutter#utility#git_supports_command_line_config_override()
let s:temp_index = tempname()
let s:temp_buffer = tempname()
" Returns a diff of the buffer.
"
" The way to get the diff depends on whether the buffer is saved or unsaved.
"
" * Saved: the buffer contents is the same as the file on disk in the working
" tree so we simply do:
"
" git diff myfile
"
" * Unsaved: the buffer contents is not the same as the file on disk so we
" need to pass two instances of the file to git-diff:
"
" git diff myfileA myfileB
"
" The first instance is the file in the index which we obtain with:
"
" git show :myfile > myfileA
"
" The second instance is the buffer contents. Ideally we would pass this to
" git-diff on stdin via the second argument to vim's system() function.
" Unfortunately git-diff does not do CRLF conversion for input received on
" stdin, and git-show never performs CRLF conversion, so repos with CRLF
" conversion report that every line is modified due to mismatching EOLs.
"
" Instead, we write the buffer contents to a temporary file - myfileB in this
" example. Note the file extension must be preserved for the CRLF
" conversion to work.
"
" Before diffing a buffer for the first time, we check whether git knows about
" the file:
"
" git ls-files --error-unmatch myfile
"
" After running the diff we pass it through grep where available to reduce
" subsequent processing by the plugin. If grep is not available the plugin
" does the filtering instead.
function! gitgutter#diff#run_diff(realtime, preserve_full_diff) abort
" Wrap compound commands in parentheses to make Windows happy.
" bash doesn't mind the parentheses.
let cmd = '('
let bufnr = gitgutter#utility#bufnr()
let tracked = gitgutter#utility#getbufvar(bufnr, 'tracked', 0) " i.e. tracked by git
if !tracked
" Don't bother trying to realtime-diff an untracked file.
" NOTE: perhaps we should pull this guard up to the caller?
if a:realtime
throw 'diff failed'
else
let cmd .= g:gitgutter_git_executable.' ls-files --error-unmatch '.gitgutter#utility#shellescape(gitgutter#utility#filename()).' && ('
endif
endif
if a:realtime
let blob_name = g:gitgutter_diff_base.':'.gitgutter#utility#shellescape(gitgutter#utility#file_relative_to_repo_root())
let blob_file = s:temp_index
let buff_file = s:temp_buffer
let extension = gitgutter#utility#extension()
if !empty(extension)
let blob_file .= '.'.extension
let buff_file .= '.'.extension
endif
let cmd .= g:gitgutter_git_executable.' show '.blob_name.' > '.blob_file.' && '
" Writing the whole buffer resets the '[ and '] marks and also the
" 'modified' flag (if &cpoptions includes '+'). These are unwanted
" side-effects so we save and restore the values ourselves.
let modified = getbufvar(bufnr, "&mod")
let op_mark_start = getpos("'[")
let op_mark_end = getpos("']")
let current_buffer = bufnr('')
execute 'buffer '.bufnr
execute 'keepalt noautocmd silent write!' buff_file
execute 'buffer '.current_buffer
call setbufvar(bufnr, "&mod", modified)
call setpos("'[", op_mark_start)
call setpos("']", op_mark_end)
endif
let cmd .= g:gitgutter_git_executable
if s:c_flag
let cmd .= ' -c "diff.autorefreshindex=0"'
let cmd .= ' -c "diff.noprefix=false"'
endif
let cmd .= ' diff --no-ext-diff --no-color -U0 '.g:gitgutter_diff_args.' '
if a:realtime
let cmd .= ' -- '.blob_file.' '.buff_file
else
let cmd .= g:gitgutter_diff_base.' -- '.gitgutter#utility#shellescape(gitgutter#utility#filename())
endif
if !a:preserve_full_diff && s:grep_available
let cmd .= ' | '.s:grep_command.' '.gitgutter#utility#shellescape('^@@ ')
endif
if (!a:preserve_full_diff && s:grep_available) || a:realtime
" grep exits with 1 when no matches are found; diff exits with 1 when
" differences are found. However we want to treat non-matches and
" differences as non-erroneous behaviour; so we OR the command with one
" which always exits with success (0).
let cmd .= ' || exit 0'
endif
let cmd .= ')'
if !tracked
let cmd .= ')'
endif
let cmd = gitgutter#utility#command_in_directory_of_file(cmd)
if g:gitgutter_async && gitgutter#async#available() && !a:preserve_full_diff
call gitgutter#async#execute(cmd)
return 'async'
else
let diff = gitgutter#utility#system(cmd)
if gitgutter#utility#shell_error()
" A shell error indicates the file is not tracked by git (unless something bizarre is going on).
throw 'diff failed'
endif
return diff
endif
endfunction
function! gitgutter#diff#parse_diff(diff) abort
let hunks = []
for line in split(a:diff, '\n')
let hunk_info = gitgutter#diff#parse_hunk(line)
if len(hunk_info) == 4
call add(hunks, hunk_info)
endif
endfor
return hunks
endfunction
function! gitgutter#diff#parse_hunk(line) abort
let matches = matchlist(a:line, s:hunk_re)
if len(matches) > 0
let from_line = str2nr(matches[1])
let from_count = (matches[2] == '') ? 1 : str2nr(matches[2])
let to_line = str2nr(matches[3])
let to_count = (matches[4] == '') ? 1 : str2nr(matches[4])
return [from_line, from_count, to_line, to_count]
else
return []
end
endfunction
function! gitgutter#diff#process_hunks(hunks) abort
let modified_lines = []
for hunk in a:hunks
call extend(modified_lines, gitgutter#diff#process_hunk(hunk))
endfor
return modified_lines
endfunction
" Returns [ [<line_number (number)>, <name (string)>], ...]
function! gitgutter#diff#process_hunk(hunk) abort
let modifications = []
let from_line = a:hunk[0]
let from_count = a:hunk[1]
let to_line = a:hunk[2]
let to_count = a:hunk[3]
if gitgutter#diff#is_added(from_count, to_count)
call gitgutter#diff#process_added(modifications, from_count, to_count, to_line)
call gitgutter#hunk#increment_lines_added(to_count)
elseif gitgutter#diff#is_removed(from_count, to_count)
call gitgutter#diff#process_removed(modifications, from_count, to_count, to_line)
call gitgutter#hunk#increment_lines_removed(from_count)
elseif gitgutter#diff#is_modified(from_count, to_count)
call gitgutter#diff#process_modified(modifications, from_count, to_count, to_line)
call gitgutter#hunk#increment_lines_modified(to_count)
elseif gitgutter#diff#is_modified_and_added(from_count, to_count)
call gitgutter#diff#process_modified_and_added(modifications, from_count, to_count, to_line)
call gitgutter#hunk#increment_lines_added(to_count - from_count)
call gitgutter#hunk#increment_lines_modified(from_count)
elseif gitgutter#diff#is_modified_and_removed(from_count, to_count)
call gitgutter#diff#process_modified_and_removed(modifications, from_count, to_count, to_line)
call gitgutter#hunk#increment_lines_modified(to_count)
call gitgutter#hunk#increment_lines_removed(from_count - to_count)
endif
return modifications
endfunction
function! gitgutter#diff#is_added(from_count, to_count) abort
return a:from_count == 0 && a:to_count > 0
endfunction
function! gitgutter#diff#is_removed(from_count, to_count) abort
return a:from_count > 0 && a:to_count == 0
endfunction
function! gitgutter#diff#is_modified(from_count, to_count) abort
return a:from_count > 0 && a:to_count > 0 && a:from_count == a:to_count
endfunction
function! gitgutter#diff#is_modified_and_added(from_count, to_count) abort
return a:from_count > 0 && a:to_count > 0 && a:from_count < a:to_count
endfunction
function! gitgutter#diff#is_modified_and_removed(from_count, to_count) abort
return a:from_count > 0 && a:to_count > 0 && a:from_count > a:to_count
endfunction
function! gitgutter#diff#process_added(modifications, from_count, to_count, to_line) abort
let offset = 0
while offset < a:to_count
let line_number = a:to_line + offset
call add(a:modifications, [line_number, 'added'])
let offset += 1
endwhile
endfunction
function! gitgutter#diff#process_removed(modifications, from_count, to_count, to_line) abort
if a:to_line == 0
call add(a:modifications, [1, 'removed_first_line'])
else
call add(a:modifications, [a:to_line, 'removed'])
endif
endfunction
function! gitgutter#diff#process_modified(modifications, from_count, to_count, to_line) abort
let offset = 0
while offset < a:to_count
let line_number = a:to_line + offset
call add(a:modifications, [line_number, 'modified'])
let offset += 1
endwhile
endfunction
function! gitgutter#diff#process_modified_and_added(modifications, from_count, to_count, to_line) abort
let offset = 0
while offset < a:from_count
let line_number = a:to_line + offset
call add(a:modifications, [line_number, 'modified'])
let offset += 1
endwhile
while offset < a:to_count
let line_number = a:to_line + offset
call add(a:modifications, [line_number, 'added'])
let offset += 1
endwhile
endfunction
function! gitgutter#diff#process_modified_and_removed(modifications, from_count, to_count, to_line) abort
let offset = 0
while offset < a:to_count
let line_number = a:to_line + offset
call add(a:modifications, [line_number, 'modified'])
let offset += 1
endwhile
let a:modifications[-1] = [a:to_line + offset - 1, 'modified_removed']
endfunction
" Generates a zero-context diff for the current hunk.
"
" diff - the full diff for the buffer
" type - stage | undo | preview
function! gitgutter#diff#generate_diff_for_hunk(diff, type) abort
let diff_for_hunk = gitgutter#diff#discard_hunks(a:diff, a:type == 'stage' || a:type == 'undo')
if a:type == 'stage' || a:type == 'undo'
let diff_for_hunk = gitgutter#diff#adjust_hunk_summary(diff_for_hunk, a:type == 'stage')
endif
return diff_for_hunk
endfunction
" Returns the diff with all hunks discarded except the current.
"
" diff - the diff to process
" keep_header - truthy to keep the diff header and hunk summary, falsy to discard it
function! gitgutter#diff#discard_hunks(diff, keep_header) abort
let modified_diff = []
let keep_line = a:keep_header
for line in split(a:diff, '\n')
let hunk_info = gitgutter#diff#parse_hunk(line)
if len(hunk_info) == 4 " start of new hunk
let keep_line = gitgutter#hunk#cursor_in_hunk(hunk_info)
endif
if keep_line
call add(modified_diff, line)
endif
endfor
if a:keep_header
return gitgutter#utility#stringify(modified_diff)
else
" Discard hunk summary too.
return gitgutter#utility#stringify(modified_diff[1:])
endif
endfunction
" Adjust hunk summary (from's / to's line number) to ignore changes above/before this one.
"
" diff_for_hunk - a diff containing only the hunk of interest
" staging - truthy if the hunk is to be staged, falsy if it is to be undone
"
" TODO: push this down to #discard_hunks?
function! gitgutter#diff#adjust_hunk_summary(diff_for_hunk, staging) abort
let line_adjustment = gitgutter#hunk#line_adjustment_for_current_hunk()
let adj_diff = []
for line in split(a:diff_for_hunk, '\n')
if match(line, s:hunk_re) != -1
if a:staging
" increment 'to' line number
let line = substitute(line, '+\@<=\(\d\+\)', '\=submatch(1)+line_adjustment', '')
else
" decrement 'from' line number
let line = substitute(line, '-\@<=\(\d\+\)', '\=submatch(1)-line_adjustment', '')
endif
endif
call add(adj_diff, line)
endfor
return gitgutter#utility#stringify(adj_diff)
endfunction