From cae4f72aa1290c353aa8d0898cac0781ef2ee538 Mon Sep 17 00:00:00 2001
From: Andy Stewart <boss@airbladesoftware.com>
Date: Fri, 13 May 2016 14:14:41 +0100
Subject: [PATCH] Abort functions at first error.

---
 autoload/gitgutter.vim           | 30 +++++++++----------
 autoload/gitgutter/async.vim     | 22 +++++++-------
 autoload/gitgutter/debug.vim     |  4 +--
 autoload/gitgutter/diff.vim      | 36 +++++++++++------------
 autoload/gitgutter/highlight.vim | 16 +++++-----
 autoload/gitgutter/hunk.vim      | 26 ++++++++---------
 autoload/gitgutter/sign.vim      | 18 ++++++------
 autoload/gitgutter/utility.vim   | 50 ++++++++++++++++----------------
 plugin/gitgutter.vim             |  2 +-
 9 files changed, 102 insertions(+), 102 deletions(-)

diff --git a/autoload/gitgutter.vim b/autoload/gitgutter.vim
index ced323a..d47ef7c 100644
--- a/autoload/gitgutter.vim
+++ b/autoload/gitgutter.vim
@@ -2,7 +2,7 @@ let s:nomodeline = (v:version > 703 || (v:version == 703 && has('patch442'))) ?
 
 " Primary functions {{{
 
-function! gitgutter#all()
+function! gitgutter#all() abort
   for buffer_id in tabpagebuflist()
     let file = expand('#' . buffer_id . ':p')
     if !empty(file)
@@ -13,7 +13,7 @@ endfunction
 
 " bufnr: (integer) the buffer to process.
 " realtime: (boolean) when truthy, do a realtime diff; otherwise do a disk-based diff.
-function! gitgutter#process_buffer(bufnr, realtime)
+function! gitgutter#process_buffer(bufnr, realtime) abort
   call gitgutter#utility#set_buffer(a:bufnr)
   if gitgutter#utility#is_active()
     if g:gitgutter_sign_column_always
@@ -37,7 +37,7 @@ function! gitgutter#process_buffer(bufnr, realtime)
 endfunction
 
 
-function! gitgutter#handle_diff(diff)
+function! gitgutter#handle_diff(diff) abort
   call gitgutter#debug#log(a:diff)
 
   call setbufvar(gitgutter#utility#bufnr(), 'gitgutter_tracked', 1)
@@ -58,7 +58,7 @@ function! gitgutter#handle_diff(diff)
   call gitgutter#utility#save_last_seen_change()
 endfunction
 
-function! gitgutter#disable()
+function! gitgutter#disable() abort
   " get list of all buffers (across all tabs)
   let buflist = []
   for i in range(tabpagenr('$'))
@@ -78,12 +78,12 @@ function! gitgutter#disable()
   let g:gitgutter_enabled = 0
 endfunction
 
-function! gitgutter#enable()
+function! gitgutter#enable() abort
   let g:gitgutter_enabled = 1
   call gitgutter#all()
 endfunction
 
-function! gitgutter#toggle()
+function! gitgutter#toggle() abort
   if g:gitgutter_enabled
     call gitgutter#disable()
   else
@@ -95,7 +95,7 @@ endfunction
 
 " Line highlights {{{
 
-function! gitgutter#line_highlights_disable()
+function! gitgutter#line_highlights_disable() abort
   let g:gitgutter_highlight_lines = 0
   call gitgutter#highlight#define_sign_line_highlights()
 
@@ -107,7 +107,7 @@ function! gitgutter#line_highlights_disable()
   redraw!
 endfunction
 
-function! gitgutter#line_highlights_enable()
+function! gitgutter#line_highlights_enable() abort
   let old_highlight_lines = g:gitgutter_highlight_lines
 
   let g:gitgutter_highlight_lines = 1
@@ -120,7 +120,7 @@ function! gitgutter#line_highlights_enable()
   redraw!
 endfunction
 
-function! gitgutter#line_highlights_toggle()
+function! gitgutter#line_highlights_toggle() abort
   if g:gitgutter_highlight_lines
     call gitgutter#line_highlights_disable()
   else
@@ -132,7 +132,7 @@ endfunction
 
 " Signs {{{
 
-function! gitgutter#signs_enable()
+function! gitgutter#signs_enable() abort
   let old_signs = g:gitgutter_signs
 
   let g:gitgutter_signs = 1
@@ -143,7 +143,7 @@ function! gitgutter#signs_enable()
   endif
 endfunction
 
-function! gitgutter#signs_disable()
+function! gitgutter#signs_disable() abort
   let g:gitgutter_signs = 0
   call gitgutter#highlight#define_sign_text_highlights()
 
@@ -153,7 +153,7 @@ function! gitgutter#signs_disable()
   endif
 endfunction
 
-function! gitgutter#signs_toggle()
+function! gitgutter#signs_toggle() abort
   if g:gitgutter_signs
     call gitgutter#signs_disable()
   else
@@ -165,7 +165,7 @@ endfunction
 
 " Hunks {{{
 
-function! gitgutter#stage_hunk()
+function! gitgutter#stage_hunk() abort
   if gitgutter#utility#is_active()
     " Ensure the working copy of the file is up to date.
     " It doesn't make sense to stage a hunk otherwise.
@@ -187,7 +187,7 @@ function! gitgutter#stage_hunk()
   endif
 endfunction
 
-function! gitgutter#undo_hunk()
+function! gitgutter#undo_hunk() abort
   if gitgutter#utility#is_active()
     " Ensure the working copy of the file is up to date.
     " It doesn't make sense to stage a hunk otherwise.
@@ -209,7 +209,7 @@ function! gitgutter#undo_hunk()
   endif
 endfunction
 
-function! gitgutter#preview_hunk()
+function! gitgutter#preview_hunk() abort
   if gitgutter#utility#is_active()
     " Ensure the working copy of the file is up to date.
     " It doesn't make sense to stage a hunk otherwise.
diff --git a/autoload/gitgutter/async.vim b/autoload/gitgutter/async.vim
index 1e4f932..443039c 100644
--- a/autoload/gitgutter/async.vim
+++ b/autoload/gitgutter/async.vim
@@ -5,7 +5,7 @@ function! gitgutter#async#available()
   return s:available
 endfunction
 
-function! gitgutter#async#execute(cmd)
+function! gitgutter#async#execute(cmd) abort
   let bufnr = gitgutter#utility#bufnr()
 
   if has('nvim')
@@ -40,7 +40,7 @@ function! gitgutter#async#execute(cmd)
 endfunction
 
 
-function! gitgutter#async#handle_diff_job_nvim(job_id, data, event)
+function! gitgutter#async#handle_diff_job_nvim(job_id, data, event) abort
   call gitgutter#debug#log('job_id: '.a:job_id.', event: '.a:event.', buffer: '.self.buffer)
 
   let current_buffer = gitgutter#utility#bufnr()
@@ -70,13 +70,13 @@ endfunction
 
 
 " Channel is in NL mode.
-function! gitgutter#async#handle_diff_job_vim(channel, line)
+function! gitgutter#async#handle_diff_job_vim(channel, line) abort
   call gitgutter#debug#log('channel: '.a:channel.', line: '.a:line)
 
   call s:accumulate_job_output(s:channel_id(a:channel), a:line)
 endfunction
 
-function! gitgutter#async#handle_diff_job_vim_close(channel)
+function! gitgutter#async#handle_diff_job_vim_close(channel) abort
   call gitgutter#debug#log('channel: '.a:channel)
 
   let channel_id = s:channel_id(a:channel)
@@ -91,7 +91,7 @@ function! gitgutter#async#handle_diff_job_vim_close(channel)
 endfunction
 
 
-function! s:channel_id(channel)
+function! s:channel_id(channel) abort
   " This seems to be the only way to get info about the channel once closed.
   return matchstr(a:channel, '\d\+')
 endfunction
@@ -122,7 +122,7 @@ endfunction
 " vim:
 "        id: channel's id
 "        arg: buffer number
-function! s:job_started(id, ...)
+function! s:job_started(id, ...) abort
   if a:0  " vim
     let s:jobs[a:id] = {'output': [], 'buffer': a:1}
   else    " nvim
@@ -130,16 +130,16 @@ function! s:job_started(id, ...)
   endif
 endfunction
 
-function! s:is_job_started(id)
+function! s:is_job_started(id) abort
   return has_key(s:jobs, a:id)
 endfunction
 
-function! s:accumulate_job_output(id, line)
+function! s:accumulate_job_output(id, line) abort
   call add(s:jobs[a:id].output, a:line)
 endfunction
 
 " Returns a string
-function! s:job_output(id)
+function! s:job_output(id) abort
   if has_key(s:jobs, a:id)
     return gitgutter#utility#stringify(s:jobs[a:id].output)
   else
@@ -147,11 +147,11 @@ function! s:job_output(id)
   endif
 endfunction
 
-function! s:job_buffer(id)
+function! s:job_buffer(id) abort
   return s:jobs[a:id].buffer
 endfunction
 
-function! s:job_finished(id)
+function! s:job_finished(id) abort
   if has_key(s:jobs, a:id)
     unlet s:jobs[a:id]
   endif
diff --git a/autoload/gitgutter/debug.vim b/autoload/gitgutter/debug.vim
index a731f0c..ad96a90 100644
--- a/autoload/gitgutter/debug.vim
+++ b/autoload/gitgutter/debug.vim
@@ -77,7 +77,7 @@ function! gitgutter#debug#output(text)
 endfunction
 
 " assumes optional args are calling function's optional args
-function! gitgutter#debug#log(message, ...)
+function! gitgutter#debug#log(message, ...) abort
   if g:gitgutter_log
     if s:new_log_session && gitgutter#async#available()
       if exists('*ch_logfile')
@@ -107,7 +107,7 @@ function! gitgutter#debug#log(message, ...)
   endif
 endfunction
 
-function! s:format_for_log(data)
+function! s:format_for_log(data) abort
   if type(a:data) == 1
     return join(split(a:data,'\n'),"\n")
   elseif type(a:data) == 3
diff --git a/autoload/gitgutter/diff.vim b/autoload/gitgutter/diff.vim
index 002f059..894be30 100644
--- a/autoload/gitgutter/diff.vim
+++ b/autoload/gitgutter/diff.vim
@@ -52,7 +52,7 @@ let s:temp_buffer = tempname()
 " 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)
+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; fish doesn't want them.
   let cmd = s:fish ? '' : '('
@@ -141,7 +141,7 @@ function! gitgutter#diff#run_diff(realtime, preserve_full_diff)
   endif
 endfunction
 
-function! gitgutter#diff#parse_diff(diff)
+function! gitgutter#diff#parse_diff(diff) abort
   let hunks = []
   for line in split(a:diff, '\n')
     let hunk_info = gitgutter#diff#parse_hunk(line)
@@ -152,7 +152,7 @@ function! gitgutter#diff#parse_diff(diff)
   return hunks
 endfunction
 
-function! gitgutter#diff#parse_hunk(line)
+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])
@@ -165,7 +165,7 @@ function! gitgutter#diff#parse_hunk(line)
   end
 endfunction
 
-function! gitgutter#diff#process_hunks(hunks)
+function! gitgutter#diff#process_hunks(hunks) abort
   call gitgutter#hunk#reset()
   let modified_lines = []
   for hunk in a:hunks
@@ -175,7 +175,7 @@ function! gitgutter#diff#process_hunks(hunks)
 endfunction
 
 " Returns [ [<line_number (number)>, <name (string)>], ...]
-function! gitgutter#diff#process_hunk(hunk)
+function! gitgutter#diff#process_hunk(hunk) abort
   let modifications = []
   let from_line  = a:hunk[0]
   let from_count = a:hunk[1]
@@ -208,27 +208,27 @@ function! gitgutter#diff#process_hunk(hunk)
   return modifications
 endfunction
 
-function! gitgutter#diff#is_added(from_count, to_count)
+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)
+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)
+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)
+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)
+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)
+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
@@ -237,7 +237,7 @@ function! gitgutter#diff#process_added(modifications, from_count, to_count, to_l
   endwhile
 endfunction
 
-function! gitgutter#diff#process_removed(modifications, from_count, to_count, to_line)
+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
@@ -245,7 +245,7 @@ function! gitgutter#diff#process_removed(modifications, from_count, to_count, to
   endif
 endfunction
 
-function! gitgutter#diff#process_modified(modifications, from_count, to_count, to_line)
+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
@@ -254,7 +254,7 @@ function! gitgutter#diff#process_modified(modifications, from_count, to_count, t
   endwhile
 endfunction
 
-function! gitgutter#diff#process_modified_and_added(modifications, from_count, to_count, to_line)
+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
@@ -268,7 +268,7 @@ function! gitgutter#diff#process_modified_and_added(modifications, from_count, t
   endwhile
 endfunction
 
-function! gitgutter#diff#process_modified_and_removed(modifications, from_count, to_count, to_line)
+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
@@ -282,7 +282,7 @@ endfunction
 "
 " diff - the full diff for the buffer
 " type - stage | undo | preview
-function! gitgutter#diff#generate_diff_for_hunk(diff, type)
+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'
@@ -296,7 +296,7 @@ endfunction
 "
 " 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)
+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')
@@ -323,7 +323,7 @@ endfunction
 " 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)
+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')
diff --git a/autoload/gitgutter/highlight.vim b/autoload/gitgutter/highlight.vim
index 616ac61..e3b774b 100644
--- a/autoload/gitgutter/highlight.vim
+++ b/autoload/gitgutter/highlight.vim
@@ -1,4 +1,4 @@
-function! gitgutter#highlight#define_sign_column_highlight()
+function! gitgutter#highlight#define_sign_column_highlight() abort
   if g:gitgutter_override_sign_column_highlight
     highlight! link SignColumn LineNr
   else
@@ -6,7 +6,7 @@ function! gitgutter#highlight#define_sign_column_highlight()
   endif
 endfunction
 
-function! gitgutter#highlight#define_highlights()
+function! gitgutter#highlight#define_highlights() abort
   let [guibg, ctermbg] = gitgutter#highlight#get_background_colors('SignColumn')
 
   " Highlights used by the signs.
@@ -34,7 +34,7 @@ function! gitgutter#highlight#define_highlights()
   highlight default link GitGutterChangeDeleteLine GitGutterChangeLine
 endfunction
 
-function! gitgutter#highlight#define_signs()
+function! gitgutter#highlight#define_signs() abort
   sign define GitGutterLineAdded
   sign define GitGutterLineModified
   sign define GitGutterLineRemoved
@@ -47,7 +47,7 @@ function! gitgutter#highlight#define_signs()
   call gitgutter#highlight#define_sign_line_highlights()
 endfunction
 
-function! gitgutter#highlight#define_sign_text()
+function! gitgutter#highlight#define_sign_text() abort
   execute "sign define GitGutterLineAdded            text=" . g:gitgutter_sign_added
   execute "sign define GitGutterLineModified         text=" . g:gitgutter_sign_modified
   execute "sign define GitGutterLineRemoved          text=" . g:gitgutter_sign_removed
@@ -55,7 +55,7 @@ function! gitgutter#highlight#define_sign_text()
   execute "sign define GitGutterLineModifiedRemoved  text=" . g:gitgutter_sign_modified_removed
 endfunction
 
-function! gitgutter#highlight#define_sign_text_highlights()
+function! gitgutter#highlight#define_sign_text_highlights() abort
   " Once a sign's text attribute has been defined, it cannot be undefined or
   " set to an empty value.  So to make signs' text disappear (when toggling
   " off or disabling) we make them invisible by setting their foreground colours
@@ -75,7 +75,7 @@ function! gitgutter#highlight#define_sign_text_highlights()
   endif
 endfunction
 
-function! gitgutter#highlight#define_sign_line_highlights()
+function! gitgutter#highlight#define_sign_line_highlights() abort
   if g:gitgutter_highlight_lines
     sign define GitGutterLineAdded            linehl=GitGutterAddLine
     sign define GitGutterLineModified         linehl=GitGutterChangeLine
@@ -91,7 +91,7 @@ function! gitgutter#highlight#define_sign_line_highlights()
   endif
 endfunction
 
-function! gitgutter#highlight#get_background_colors(group)
+function! gitgutter#highlight#get_background_colors(group) abort
   redir => highlight
   silent execute 'silent highlight ' . a:group
   redir END
@@ -106,7 +106,7 @@ function! gitgutter#highlight#get_background_colors(group)
   return [guibg, ctermbg]
 endfunction
 
-function! gitgutter#highlight#match_highlight(highlight, pattern)
+function! gitgutter#highlight#match_highlight(highlight, pattern) abort
   let matches = matchlist(a:highlight, a:pattern)
   if len(matches) == 0
     return 'NONE'
diff --git a/autoload/gitgutter/hunk.vim b/autoload/gitgutter/hunk.vim
index 24a9a78..13afb94 100644
--- a/autoload/gitgutter/hunk.vim
+++ b/autoload/gitgutter/hunk.vim
@@ -2,35 +2,35 @@
 let s:summary = [0, 0, 0]
 let s:hunks = []
 
-function! gitgutter#hunk#set_hunks(hunks)
+function! gitgutter#hunk#set_hunks(hunks) abort
   let s:hunks = a:hunks
 endfunction
 
-function! gitgutter#hunk#hunks()
+function! gitgutter#hunk#hunks() abort
   return s:hunks
 endfunction
 
-function! gitgutter#hunk#summary()
+function! gitgutter#hunk#summary() abort
   return s:summary
 endfunction
 
-function! gitgutter#hunk#reset()
+function! gitgutter#hunk#reset() abort
   let s:summary = [0, 0, 0]
 endfunction
 
-function! gitgutter#hunk#increment_lines_added(count)
+function! gitgutter#hunk#increment_lines_added(count) abort
   let s:summary[0] += a:count
 endfunction
 
-function! gitgutter#hunk#increment_lines_modified(count)
+function! gitgutter#hunk#increment_lines_modified(count) abort
   let s:summary[1] += a:count
 endfunction
 
-function! gitgutter#hunk#increment_lines_removed(count)
+function! gitgutter#hunk#increment_lines_removed(count) abort
   let s:summary[2] += a:count
 endfunction
 
-function! gitgutter#hunk#next_hunk(count)
+function! gitgutter#hunk#next_hunk(count) abort
   if gitgutter#utility#is_active()
     let current_line = line('.')
     let hunk_count = 0
@@ -47,7 +47,7 @@ function! gitgutter#hunk#next_hunk(count)
   endif
 endfunction
 
-function! gitgutter#hunk#prev_hunk(count)
+function! gitgutter#hunk#prev_hunk(count) abort
   if gitgutter#utility#is_active()
     let current_line = line('.')
     let hunk_count = 0
@@ -67,7 +67,7 @@ endfunction
 
 " Returns the hunk the cursor is currently in or an empty list if the cursor
 " isn't in a hunk.
-function! gitgutter#hunk#current_hunk()
+function! gitgutter#hunk#current_hunk() abort
   let current_hunk = []
 
   for hunk in s:hunks
@@ -80,7 +80,7 @@ function! gitgutter#hunk#current_hunk()
   return current_hunk
 endfunction
 
-function! gitgutter#hunk#cursor_in_hunk(hunk)
+function! gitgutter#hunk#cursor_in_hunk(hunk) abort
   let current_line = line('.')
 
   if current_line == 1 && a:hunk[2] == 0
@@ -96,7 +96,7 @@ endfunction
 
 " Returns the number of lines the current hunk is offset from where it would
 " be if any changes above it in the file didn't exist.
-function! gitgutter#hunk#line_adjustment_for_current_hunk()
+function! gitgutter#hunk#line_adjustment_for_current_hunk() abort
   let adj = 0
   for hunk in s:hunks
     if gitgutter#hunk#cursor_in_hunk(hunk)
@@ -108,7 +108,7 @@ function! gitgutter#hunk#line_adjustment_for_current_hunk()
   return adj
 endfunction
 
-function! gitgutter#hunk#text_object(inner)
+function! gitgutter#hunk#text_object(inner) abort
   let hunk = gitgutter#hunk#current_hunk()
 
   if empty(hunk)
diff --git a/autoload/gitgutter/sign.vim b/autoload/gitgutter/sign.vim
index e520c50..6bd5efa 100644
--- a/autoload/gitgutter/sign.vim
+++ b/autoload/gitgutter/sign.vim
@@ -11,7 +11,7 @@ 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()
+function! gitgutter#sign#clear_signs() abort
   let bufnr = gitgutter#utility#bufnr()
   call gitgutter#sign#find_current_signs()
 
@@ -25,7 +25,7 @@ endfunction
 "
 " modified_lines: list of [<line_number (number)>, <name (string)>]
 " where name = 'added|removed|modified|modified_removed'
-function! gitgutter#sign#update_signs(modified_lines)
+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]')
@@ -45,7 +45,7 @@ function! gitgutter#sign#update_signs(modified_lines)
 endfunction
 
 
-function! gitgutter#sign#add_dummy_sign()
+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
@@ -53,7 +53,7 @@ function! gitgutter#sign#add_dummy_sign()
   endif
 endfunction
 
-function! gitgutter#sign#remove_dummy_sign(force)
+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
@@ -67,7 +67,7 @@ endfunction
 "
 
 
-function! gitgutter#sign#find_current_signs()
+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),...]
@@ -109,7 +109,7 @@ 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)
+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
@@ -126,7 +126,7 @@ function! gitgutter#sign#obsolete_gitgutter_signs_to_remove(new_gitgutter_signs_
 endfunction
 
 
-function! gitgutter#sign#remove_signs(sign_ids, all_signs)
+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')
@@ -142,7 +142,7 @@ function! gitgutter#sign#remove_signs(sign_ids, all_signs)
 endfunction
 
 
-function! gitgutter#sign#upsert_new_gitgutter_signs(modified_lines)
+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')
@@ -166,7 +166,7 @@ function! gitgutter#sign#upsert_new_gitgutter_signs(modified_lines)
 endfunction
 
 
-function! gitgutter#sign#next_sign_id()
+function! gitgutter#sign#next_sign_id() abort
   let next_id = s:next_sign_id
   let s:next_sign_id += 1
   return next_id
diff --git a/autoload/gitgutter/utility.vim b/autoload/gitgutter/utility.vim
index 32856d5..6e0c886 100644
--- a/autoload/gitgutter/utility.vim
+++ b/autoload/gitgutter/utility.vim
@@ -3,14 +3,14 @@ let s:using_xolox_shell = -1
 let s:exit_code = 0
 let s:fish = &shell =~# 'fish'
 
-function! gitgutter#utility#warn(message)
+function! gitgutter#utility#warn(message) abort
   echohl WarningMsg
   echo 'vim-gitgutter: ' . a:message
   echohl None
   let v:warningmsg = a:message
 endfunction
 
-function! gitgutter#utility#warn_once(message, key)
+function! gitgutter#utility#warn_once(message, key) abort
   if empty(getbufvar(s:bufnr, a:key))
     call setbufvar(s:bufnr, a:key, '1')
     echohl WarningMsg
@@ -22,7 +22,7 @@ endfunction
 
 " Returns truthy when the buffer's file should be processed; and falsey when it shouldn't.
 " This function does not and should not make any system calls.
-function! gitgutter#utility#is_active()
+function! gitgutter#utility#is_active() abort
   return g:gitgutter_enabled &&
         \ !pumvisible() &&
         \ gitgutter#utility#is_file_buffer() &&
@@ -30,11 +30,11 @@ function! gitgutter#utility#is_active()
         \ gitgutter#utility#not_git_dir()
 endfunction
 
-function! gitgutter#utility#not_git_dir()
+function! gitgutter#utility#not_git_dir() abort
   return gitgutter#utility#full_path_to_directory_of_file() !~ '[/\\]\.git\($\|[/\\]\)'
 endfunction
 
-function! gitgutter#utility#is_file_buffer()
+function! gitgutter#utility#is_file_buffer() abort
   return empty(getbufvar(s:bufnr, '&buftype'))
 endfunction
 
@@ -45,7 +45,7 @@ endfunction
 "
 " See:
 " https://github.com/tpope/vim-fugitive/blob/8f0b8edfbd246c0026b7a2388e1d883d579ac7f6/plugin/fugitive.vim#L29-L37
-function! gitgutter#utility#shellescape(arg)
+function! gitgutter#utility#shellescape(arg) abort
   if a:arg =~ '^[A-Za-z0-9_/.-]\+$'
     return a:arg
   elseif &shell =~# 'cmd' || gitgutter#utility#using_xolox_shell()
@@ -55,7 +55,7 @@ function! gitgutter#utility#shellescape(arg)
   endif
 endfunction
 
-function! gitgutter#utility#set_buffer(bufnr)
+function! gitgutter#utility#set_buffer(bufnr) abort
   let s:bufnr = a:bufnr
   let s:file = resolve(bufname(a:bufnr))
 endfunction
@@ -68,43 +68,43 @@ function! gitgutter#utility#file()
   return s:file
 endfunction
 
-function! gitgutter#utility#filename()
+function! gitgutter#utility#filename() abort
   return fnamemodify(s:file, ':t')
 endfunction
 
-function! gitgutter#utility#extension()
+function! gitgutter#utility#extension() abort
   return fnamemodify(s:file, ':e')
 endfunction
 
-function! gitgutter#utility#full_path_to_directory_of_file()
+function! gitgutter#utility#full_path_to_directory_of_file() abort
   return fnamemodify(s:file, ':p:h')
 endfunction
 
-function! gitgutter#utility#directory_of_file()
+function! gitgutter#utility#directory_of_file() abort
   return fnamemodify(s:file, ':h')
 endfunction
 
-function! gitgutter#utility#exists_file()
+function! gitgutter#utility#exists_file() abort
   return filereadable(s:file)
 endfunction
 
-function! gitgutter#utility#has_unsaved_changes()
+function! gitgutter#utility#has_unsaved_changes() abort
   return getbufvar(s:bufnr, "&mod")
 endfunction
 
-function! gitgutter#utility#has_fresh_changes()
+function! gitgutter#utility#has_fresh_changes() abort
   return getbufvar(s:bufnr, 'changedtick') != getbufvar(s:bufnr, 'gitgutter_last_tick')
 endfunction
 
-function! gitgutter#utility#save_last_seen_change()
+function! gitgutter#utility#save_last_seen_change() abort
   call setbufvar(s:bufnr, 'gitgutter_last_tick', getbufvar(s:bufnr, 'changedtick'))
 endfunction
 
-function! gitgutter#utility#shell_error()
+function! gitgutter#utility#shell_error() abort
   return gitgutter#utility#using_xolox_shell() ? s:exit_code : v:shell_error
 endfunction
 
-function! gitgutter#utility#using_xolox_shell()
+function! gitgutter#utility#using_xolox_shell() abort
   if s:using_xolox_shell == -1
     if !g:gitgutter_avoid_cmd_prompt_on_windows
       let s:using_xolox_shell = 0
@@ -119,7 +119,7 @@ function! gitgutter#utility#using_xolox_shell()
   return s:using_xolox_shell
 endfunction
 
-function! gitgutter#utility#system(cmd, ...)
+function! gitgutter#utility#system(cmd, ...) abort
   call gitgutter#debug#log(a:cmd, a:000)
 
   if gitgutter#utility#using_xolox_shell()
@@ -136,7 +136,7 @@ function! gitgutter#utility#system(cmd, ...)
   return output
 endfunction
 
-function! gitgutter#utility#file_relative_to_repo_root()
+function! gitgutter#utility#file_relative_to_repo_root() abort
   let file_path_relative_to_repo_root = getbufvar(s:bufnr, 'gitgutter_repo_relative_path')
   if empty(file_path_relative_to_repo_root)
     let dir_path_relative_to_repo_root = gitgutter#utility#system(gitgutter#utility#command_in_directory_of_file('git rev-parse --show-prefix'))
@@ -147,11 +147,11 @@ function! gitgutter#utility#file_relative_to_repo_root()
   return file_path_relative_to_repo_root
 endfunction
 
-function! gitgutter#utility#command_in_directory_of_file(cmd)
+function! gitgutter#utility#command_in_directory_of_file(cmd) abort
   return 'cd '.gitgutter#utility#shellescape(gitgutter#utility#directory_of_file()) . (s:fish ? '; and ' : ' && ') . a:cmd
 endfunction
 
-function! gitgutter#utility#highlight_name_for_change(text)
+function! gitgutter#utility#highlight_name_for_change(text) abort
   if a:text ==# 'added'
     return 'GitGutterLineAdded'
   elseif a:text ==# 'removed'
@@ -165,20 +165,20 @@ function! gitgutter#utility#highlight_name_for_change(text)
   endif
 endfunction
 
-function! gitgutter#utility#strip_trailing_new_line(line)
+function! gitgutter#utility#strip_trailing_new_line(line) abort
   return substitute(a:line, '\n$', '', '')
 endfunction
 
-function! gitgutter#utility#git_version()
+function! gitgutter#utility#git_version() abort
   return matchstr(system('git --version'), '[0-9.]\+')
 endfunction
 
 " True for git v1.7.2+.
-function! gitgutter#utility#git_supports_command_line_config_override()
+function! gitgutter#utility#git_supports_command_line_config_override() abort
   let [major, minor, patch; _] = split(gitgutter#utility#git_version(), '\.')
   return major > 1 || (major == 1 && minor > 7) || (minor == 7 && patch > 1)
 endfunction
 
-function! gitgutter#utility#stringify(list)
+function! gitgutter#utility#stringify(list) abort
   return join(a:list, "\n")."\n"
 endfunction
diff --git a/plugin/gitgutter.vim b/plugin/gitgutter.vim
index 608f73f..db7ac44 100644
--- a/plugin/gitgutter.vim
+++ b/plugin/gitgutter.vim
@@ -17,7 +17,7 @@ if !exists("*gettabvar")
   let g:gitgutter_eager = 0
 endif
 
-function! s:set(var, default)
+function! s:set(var, default) abort
   if !exists(a:var)
     if type(a:default)
       execute 'let' a:var '=' string(a:default)