Merge pull request rhysd#118 from jreybert/git_diff

Add git_diff behavior

Author: rhysd

Diff for: autoload/clang_format.vim

@@ -139,6 +139,14 @@ function! clang_format#is_invalid() abort
         let s:version = v
     endif
 
+    if g:clang_format#auto_format_git_diff &&
+                \ !exists('s:git_available')
+        if !executable(g:clang_format#git)
+            return 1
+        endif
+        let s:git_available = 1
+    endif
+
     return 0
 endfunction
 
@@ -184,6 +192,7 @@ let g:clang_format#extra_args = s:getg('clang_format#extra_args', "")
 if type(g:clang_format#extra_args) == type([])
     let g:clang_format#extra_args = join(g:clang_format#extra_args, " ")
 endif
+let g:clang_format#git = s:getg('clang_format#git', 'git')
 
 let g:clang_format#code_style = s:getg('clang_format#code_style', 'google')
 let g:clang_format#style_options = s:getg('clang_format#style_options', {})
@@ -193,6 +202,8 @@ let g:clang_format#detect_style_file = s:getg('clang_format#detect_style_file',
 let g:clang_format#enable_fallback_style = s:getg('clang_format#enable_fallback_style', 1)
 
 let g:clang_format#auto_format = s:getg('clang_format#auto_format', 0)
+let g:clang_format#auto_format_git_diff = s:getg('clang_format#auto_format_git_diff', 0)
+let g:clang_format#auto_format_git_diff_fallback = s:getg('clang_format#auto_format_git_diff_fallback', 'file')
 let g:clang_format#auto_format_on_insert_leave = s:getg('clang_format#auto_format_on_insert_leave', 0)
 let g:clang_format#auto_formatexpr = s:getg('clang_format#auto_formatexpr', 0)
 let g:clang_format#auto_filetypes = s:getg( 'clang_format#auto_filetypes',
@@ -206,8 +217,13 @@ function! s:detect_style_file() abort
     return findfile('.clang-format', dirname.';') != '' || findfile('_clang-format', dirname.';') != ''
 endfunction
 
-function! clang_format#format(line1, line2) abort
-    let args = printf(' -lines=%d:%d', a:line1, a:line2)
+" clang_format#format_ranges is were the magic happends.
+" ranges is a list of pairs, like [[start1,end1],[start2,end2]...]
+function! clang_format#format_ranges(ranges) abort
+    let args = ''
+    for range in a:ranges
+        let args .= printf(' -lines=%d:%d', range[0], range[1])
+    endfor
     if ! (g:clang_format#detect_style_file && s:detect_style_file())
         if g:clang_format#enable_fallback_style
             let args .= ' ' . s:shellescape(printf('-style=%s', s:make_style_options())) . ' '
@@ -226,14 +242,18 @@ function! clang_format#format(line1, line2) abort
     let source = join(getline(1, '$'), "\n")
     return s:system(clang_format, source)
 endfunction
+
+function! clang_format#format(line1, line2) abort
+    return clang_format#format_ranges([[line1, line2]])
+endfunction
 " }}}
 
 " replace buffer {{{
-function! clang_format#replace(line1, line2, ...) abort
+function! clang_format#replace_ranges(ranges, ...) abort
     call s:verify_command()
 
     let pos_save = a:0 >= 1 ? a:1 : getpos('.')
-    let formatted = clang_format#format(a:line1, a:line2)
+    let formatted = clang_format#format_ranges(a:ranges)
     if !s:success(formatted)
         call s:error_message(formatted)
         return
@@ -250,6 +270,10 @@ function! clang_format#replace(line1, line2, ...) abort
     call winrestview(winview)
     call setpos('.', pos_save)
 endfunction
+
+function! clang_format#replace(line1, line2, ...) abort
+    call call(function("clang_format#replace_ranges"), [[line1, line2]], a:000)
+endfunction
 " }}}
 
 " auto formatting on insert leave {{{
@@ -294,6 +318,91 @@ endfunction
 function! clang_format#disable_auto_format() abort
     let g:clang_format#auto_format = 0
 endfunction
+
+" s:strip: helper function to strip a string
+function! s:strip(string)
+    return substitute(a:string, '^\s*\(.\{-}\)\s*\r\=\n\=$', '\1', '')
+endfunction
+
+" clang_format#get_git_diff
+" a:file must be an absolute path to the file to be processed
+" this function compares the current buffer content against the
+" git index content of the file.
+" this function returns a list of pair of ranges if the file is tracked
+" and has changes, an empty list otherwise
+function! clang_format#get_git_diff(cur_file)
+    let file_path = isdirectory(a:cur_file) ? a:cur_file :
+                \ fnamemodify(a:cur_file, ":h")
+    let top_dir=s:strip(system(
+                \ g:clang_format#git." -C ".shellescape(file_path).
+                \ " rev-parse --show-toplevel"))
+    if v:shell_error != 0
+        return []
+    endif
+    let cur_file = s:strip(s:system(
+                \ g:clang_format#git." -C ".shellescape(top_dir).
+                \ " ls-files --error-unmatch ".shellescape(a:cur_file)))
+    if v:shell_error != 0
+        return []
+    endif
+    let source = join(getline(1, '$'), "\n")
+    " git show :file shows the staged content of the file:
+    "  - content in index if any (staged but not commmited)
+    "  - else content in HEAD
+    " this solution also solves the problem for 'git mv'ed file:
+    "  - if the current buffer has been renamed by simple mv (without git
+    "    add), the file is considered as untracked
+    "  - if the renamed file has been git added or git mv, git show :file
+    "    will show the expected content.
+    " this barbarian command does the following:
+    "  - diff --*-group-* options will return ranges (start,end) for each
+    "    diff chunk
+    "  - <(git show :file) is a process substitution, using /dev/fd/<n> as
+    "    temporary file for the output
+    "  - - is stdin, which is current buffer content in variable 'source'
+    let diff_cmd =
+            \ 'diff <('.g:clang_format#git.' show :'.shellescape(cur_file).') - '.
+            \ '--old-group-format="" --unchanged-group-format="" '.
+            \ '--new-group-format="%dF-%dL%c''\\012''" '.
+            \ '--changed-group-format="%dF-%dL%c''\\012''"'
+    let ranges = s:system(diff_cmd, source)
+    if !(v:shell_error == 0 || v:shell_error == 1)
+        throw printf("clang-format: git diff failed `%s` for ranges %s",
+                    \ diff_cmd, ranges)
+    endif
+    let ranges = split(ranges, '\n')
+    " ranges is now a list of pairs [[start1, end1],[start2,end2]...]
+    let ranges = map(ranges, "split(v:val, '-')")
+    return ranges
+endfunction
+
+" this function will try to format only buffer lines diffing from git index
+" content.
+" If the file is untracked (not in a git repo or not tracked in a git repo),
+" it returns 1.
+" If the format succeeds, it returns 0.
+function! clang_format#do_auto_format_git_diff()
+    let cur_file = expand("%:p")
+    let ranges = clang_format#get_git_diff(cur_file)
+    if !empty(ranges)
+        call clang_format#replace_ranges(ranges)
+        return 0
+    else
+        return 1
+    endif
+endfunction
+
+function! clang_format#do_auto_format()
+    if g:clang_format#auto_format_git_diff
+        let ret = clang_format#do_auto_format_git_diff()
+        if ret == 0 ||
+           \ g:clang_format#auto_format_git_diff_fallback != 'file'
+            return
+        endif
+    endif
+    call clang_format#replace_ranges([[1, line('$')]])
+endfunction
+
 " }}}
 let &cpo = s:save_cpo
 unlet s:save_cpo

Diff for: doc/clang-format.txt

@@ -128,6 +128,11 @@ g:clang_format#command                                  *g:clang_format#command*
     Name of clang-format command.
     The default value is "clang-format".
 
+g:clang_format#git                                          *g:clang_format#git*
+
+    Name of the git command.
+    The default value is "git".
+
 g:clang_format#code_style                            *g:clang_format#code_style*
 
     Base coding style for formatting.  Available coding styles are "llvm",
@@ -187,6 +192,25 @@ g:clang_format#auto_format                          *g:clang_format#auto_format*
     buffer on saving the buffer.  Formatting is executed at |BufWritePre| event.
     The default value is 0.
 
+g:clang_format#auto_format_git_diff        *g:clang_format#auto_format_git_diff*
+
+    When this value is 1, and when g:clang_format#auto_format is 1, the auto
+    format only formats modified lines is the file is tracked in git.
+    If the file is not tracked, or even not in a git project, fallback
+    behavior depends on |g:clang_format#auto_format_git_diff_fallback|.
+    WARNING: this option should not be used with
+    |g:clang_format#auto_format_on_insert_leave|.
+    The default value is 0.
+
+g:clang_format#auto_format_git_diff_fallback
+                                  *g:clang_format#auto_format_git_diff_fallback*
+
+    Fallback behavior when |g:clang_format#auto_format_git_diff| is 1 and the
+    current file is not tracked. The value can be:
+    - 'file': the whole file is formatted (which is the default
+      |g:clang_format#auto_format| behavior).
+    - 'pass': the file is not formatted.
+
 g:clang_format#auto_format_on_insert_leave
                                     *g:clang_format#auto_format_on_insert_leave*
 

Diff for: plugin/clang_format.vim

@@ -22,7 +22,7 @@ augroup plugin-clang-format-auto-format
         \ if index(g:clang_format#auto_filetypes, &ft) >= 0 &&
         \     g:clang_format#auto_format &&
         \     !clang_format#is_invalid() |
-        \     call clang_format#replace(1, line('$')) |
+        \     call clang_format#do_auto_format() |
         \ endif
     autocmd FileType *
         \ if index(g:clang_format#auto_filetypes, &ft) >= 0 &&