1 files changed, 173 insertions, 0 deletions
diff --git a/vim/bundle/vim-gitgutter/autoload/gitgutter/sign.vim b/vim/bundle/vim-gitgutter/autoload/gitgutter/sign.vim
new file mode 100644
index 0000000..6bd5efa
--- /dev/null
+++ b/vim/bundle/vim-gitgutter/autoload/gitgutter/sign.vim
@@ -0,0 +1,173 @@
+" Vim doesn't namespace sign ids so every plugin shares the same
+" namespace.  Sign ids are simply integers so to avoid clashes with other
+" signs we guess at a clear run.
+"
+" Note also we currently never reset s:next_sign_id.
+let s:first_sign_id = 3000
+let s:next_sign_id  = s:first_sign_id
+let s:dummy_sign_id = s:first_sign_id - 1
+" Remove-all-signs optimisation requires Vim 7.3.596+.
+let s:supports_star = v:version > 703 || (v:version == 703 && has("patch596"))
+
+
+" Removes gitgutter's signs (excluding dummy sign) from the buffer being processed.
+function! gitgutter#sign#clear_signs() abort
+  let bufnr = gitgutter#utility#bufnr()
+  call gitgutter#sign#find_current_signs()
+
+  let sign_ids = map(values(getbufvar(bufnr, 'gitgutter_gitgutter_signs')), 'v:val.id')
+  call gitgutter#sign#remove_signs(sign_ids, 1)
+  call setbufvar(bufnr, 'gitgutter_gitgutter_signs', {})
+endfunction
+
+
+" Updates gitgutter's signs in the buffer being processed.
+"
+" modified_lines: list of [<line_number (number)>, <name (string)>]
+" where name = 'added|removed|modified|modified_removed'
+function! gitgutter#sign#update_signs(modified_lines) abort
+  call gitgutter#sign#find_current_signs()
+
+  let new_gitgutter_signs_line_numbers = map(copy(a:modified_lines), 'v:val[0]')
+  let obsolete_signs = gitgutter#sign#obsolete_gitgutter_signs_to_remove(new_gitgutter_signs_line_numbers)
+
+  let flicker_possible = s:remove_all_old_signs && !empty(a:modified_lines)
+  if flicker_possible
+    call gitgutter#sign#add_dummy_sign()
+  endif
+
+  call gitgutter#sign#remove_signs(obsolete_signs, s:remove_all_old_signs)
+  call gitgutter#sign#upsert_new_gitgutter_signs(a:modified_lines)
+
+  if flicker_possible
+    call gitgutter#sign#remove_dummy_sign(0)
+  endif
+endfunction
+
+
+function! gitgutter#sign#add_dummy_sign() abort
+  let bufnr = gitgutter#utility#bufnr()
+  if !getbufvar(bufnr, 'gitgutter_dummy_sign')
+    execute "sign place" s:dummy_sign_id "line=" . 9999 "name=GitGutterDummy buffer=" . bufnr
+    call setbufvar(bufnr, 'gitgutter_dummy_sign', 1)
+  endif
+endfunction
+
+function! gitgutter#sign#remove_dummy_sign(force) abort
+  let bufnr = gitgutter#utility#bufnr()
+  if getbufvar(bufnr, 'gitgutter_dummy_sign') && (a:force || !g:gitgutter_sign_column_always)
+    execute "sign unplace" s:dummy_sign_id "buffer=" . bufnr
+    call setbufvar(bufnr, 'gitgutter_dummy_sign', 0)
+  endif
+endfunction
+
+
+"
+" Internal functions
+"
+
+
+function! gitgutter#sign#find_current_signs() abort
+  let bufnr = gitgutter#utility#bufnr()
+  let gitgutter_signs = {}  " <line_number (string)>: {'id': <id (number)>, 'name': <name (string)>}
+  let other_signs = []      " [<line_number (number),...]
+  let dummy_sign_placed = 0
+
+  redir => signs
+    silent execute "sign place buffer=" . bufnr
+  redir END
+
+  for sign_line in filter(split(signs, '\n')[2:], 'v:val =~# "="')
+    " Typical sign line:  line=88 id=1234 name=GitGutterLineAdded
+    " We assume splitting is faster than a regexp.
+    let components  = split(sign_line)
+    let name        = split(components[2], '=')[1]
+    if name =~# 'GitGutterDummy'
+      let dummy_sign_placed = 1
+    else
+      let line_number = str2nr(split(components[0], '=')[1])
+      if name =~# 'GitGutter'
+        let id = str2nr(split(components[1], '=')[1])
+        " Remove orphaned signs (signs placed on lines which have been deleted).
+        " (When a line is deleted its sign lingers.  Subsequent lines' signs'
+        " line numbers are decremented appropriately.)
+        if has_key(gitgutter_signs, line_number)
+          execute "sign unplace" gitgutter_signs[line_number].id
+        endif
+        let gitgutter_signs[line_number] = {'id': id, 'name': name}
+      else
+        call add(other_signs, line_number)
+      endif
+    end
+  endfor
+
+  call setbufvar(bufnr, 'gitgutter_dummy_sign', dummy_sign_placed)
+  call setbufvar(bufnr, 'gitgutter_gitgutter_signs', gitgutter_signs)
+  call setbufvar(bufnr, 'gitgutter_other_signs', other_signs)
+endfunction
+
+
+" Returns a list of [<id (number)>, ...]
+" Sets `s:remove_all_old_signs` as a side-effect.
+function! gitgutter#sign#obsolete_gitgutter_signs_to_remove(new_gitgutter_signs_line_numbers) abort
+  let bufnr = gitgutter#utility#bufnr()
+  let signs_to_remove = []  " list of [<id (number)>, ...]
+  let remove_all_signs = 1
+  let old_gitgutter_signs = getbufvar(bufnr, 'gitgutter_gitgutter_signs')
+  for line_number in keys(old_gitgutter_signs)
+    if index(a:new_gitgutter_signs_line_numbers, str2nr(line_number)) == -1
+      call add(signs_to_remove, old_gitgutter_signs[line_number].id)
+    else
+      let remove_all_signs = 0
+    endif
+  endfor
+  let s:remove_all_old_signs = remove_all_signs
+  return signs_to_remove
+endfunction
+
+
+function! gitgutter#sign#remove_signs(sign_ids, all_signs) abort
+  let bufnr = gitgutter#utility#bufnr()
+  if a:all_signs && s:supports_star && empty(getbufvar(bufnr, 'gitgutter_other_signs'))
+    let dummy_sign_present = getbufvar(bufnr, 'gitgutter_dummy_sign')
+    execute "sign unplace * buffer=" . bufnr
+    if dummy_sign_present
+      execute "sign place" s:dummy_sign_id "line=" . 9999 "name=GitGutterDummy buffer=" . bufnr
+    endif
+  else
+    for id in a:sign_ids
+      execute "sign unplace" id
+    endfor
+  endif
+endfunction
+
+
+function! gitgutter#sign#upsert_new_gitgutter_signs(modified_lines) abort
+  let bufnr = gitgutter#utility#bufnr()
+  let other_signs         = getbufvar(bufnr, 'gitgutter_other_signs')
+  let old_gitgutter_signs = getbufvar(bufnr, 'gitgutter_gitgutter_signs')
+
+  for line in a:modified_lines
+    let line_number = line[0]  " <number>
+    if index(other_signs, line_number) == -1  " don't clobber others' signs
+      let name = gitgutter#utility#highlight_name_for_change(line[1])
+      if !has_key(old_gitgutter_signs, line_number)  " insert
+        let id = gitgutter#sign#next_sign_id()
+        execute "sign place" id "line=" . line_number "name=" . name "buffer=" . bufnr
+      else  " update if sign has changed
+        let old_sign = old_gitgutter_signs[line_number]
+        if old_sign.name !=# name
+          execute "sign place" old_sign.id "name=" . name "buffer=" . bufnr
+        end
+      endif
+    endif
+  endfor
+  " At this point b:gitgutter_gitgutter_signs is out of date.
+endfunction
+
+
+function! gitgutter#sign#next_sign_id() abort
+  let next_id = s:next_sign_id
+  let s:next_sign_id += 1
+  return next_id
+endfunction