1 files changed, 78 insertions, 0 deletions
diff --git a/runtime/indent/go.vim b/runtime/indent/go.vim
new file mode 100644
index 0000000000..412ac871c4
--- /dev/null
+++ b/runtime/indent/go.vim
@@ -0,0 +1,78 @@
+" Vim indent file
+" Language:	Go
+" Maintainer:	David Barnett (https://github.com/google/vim-ft-go)
+" Last Change:	2014 Aug 16
+"
+" TODO:
+" - function invocations split across lines
+" - general line splits (line ends in an operator)
+
+if exists('b:did_indent')
+  finish
+endif
+let b:did_indent = 1
+
+" C indentation is too far off useful, mainly due to Go's := operator.
+" Let's just define our own.
+setlocal nolisp
+setlocal autoindent
+setlocal indentexpr=GoIndent(v:lnum)
+setlocal indentkeys+=<:>,0=},0=)
+
+if exists('*GoIndent')
+  finish
+endif
+
+" The shiftwidth() function is relatively new.
+" Don't require it to exist.
+if exists('*shiftwidth')
+  function s:sw() abort
+    return shiftwidth()
+  endfunction
+else
+  function s:sw() abort
+    return &shiftwidth
+  endfunction
+endif
+
+function! GoIndent(lnum)
+  let l:prevlnum = prevnonblank(a:lnum-1)
+  if l:prevlnum == 0
+    " top of file
+    return 0
+  endif
+
+  " grab the previous and current line, stripping comments.
+  let l:prevl = substitute(getline(l:prevlnum), '//.*$', '', '')
+  let l:thisl = substitute(getline(a:lnum), '//.*$', '', '')
+  let l:previ = indent(l:prevlnum)
+
+  let l:ind = l:previ
+
+  if l:prevl =~ '[({]\s*$'
+    " previous line opened a block
+    let l:ind += s:sw()
+  endif
+  if l:prevl =~# '^\s*\(case .*\|default\):$'
+    " previous line is part of a switch statement
+    let l:ind += s:sw()
+  endif
+  " TODO: handle if the previous line is a label.
+
+  if l:thisl =~ '^\s*[)}]'
+    " this line closed a block
+    let l:ind -= s:sw()
+  endif
+
+  " Colons are tricky.
+  " We want to outdent if it's part of a switch ("case foo:" or "default:").
+  " We ignore trying to deal with jump labels because (a) they're rare, and
+  " (b) they're hard to disambiguate from a composite literal key.
+  if l:thisl =~# '^\s*\(case .*\|default\):$'
+    let l:ind -= s:sw()
+  endif
+
+  return l:ind
+endfunction
+
+" vim: sw=2 sts=2 et