Add ktfmt support. Fixes google#176.

Unfortunately, ktfmt doesn't yet support a --lines option to format a
range. See facebook/ktfmt#218 for the
feature request.

Author: flwyd

README.md

@@ -23,6 +23,7 @@ helpfiles in the `doc/` directory. The helpfiles are also available via
 * Java (google-java-format or clang-format)
 * JavaScript (clang-format or [prettier](https://prettier.io))
 * JSON (js-beautify)
+* Kotlin ([ktfmt](https://github.com/facebookincubator/ktfmt))
 * Proto (clang-format)
 * Python (Autopep8, Black, or YAPF)
 * Rust ([rustfmt](https://github.com/rust-lang/rustfmt))

autoload/codefmt/ktfmt.vim

@@ -0,0 +1,82 @@
+" Copyright 2017 Google Inc. All rights reserved.
+"
+" Licensed under the Apache License, Version 2.0 (the "License");
+" you may not use this file except in compliance with the License.
+" You may obtain a copy of the License at
+"
+"     http://www.apache.org/licenses/LICENSE-2.0
+"
+" Unless required by applicable law or agreed to in writing, software
+" distributed under the License is distributed on an "AS IS" BASIS,
+" WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+" See the License for the specific language governing permissions and
+" limitations under the License.
+
+
+let s:plugin = maktaba#plugin#Get('codefmt')
+
+""
+" @private
+" Formatter: ktfmt
+function! codefmt#ktfmt#GetFormatter() abort
+  let l:formatter = {
+      \ 'name': 'ktfmt',
+      \ 'setup_instructions': 'Install ktfmt ' .
+          \ "(https://github.com/facebookincubator/ktfmt).\n" .
+          \ 'Enable with "Glaive codefmt ktfmt_executable=' .
+          \ '"java -jar /path/to/ktfmt-<VERSION>-jar-with-dependencies.jar" ' .
+          \ 'in your .vimrc' }
+
+  function l:formatter.IsAvailable() abort
+    let l:exec = s:plugin.Flag('ktfmt_executable')
+    if executable(l:exec)
+      return 1
+    elseif !empty(l:exec) && l:exec isnot# 'ktfmt'
+      " The user has specified a custom formatter command. Hope it works.
+      return 1
+    else
+      return 0
+    endif
+  endfunction
+
+  function l:formatter.AppliesToBuffer() abort
+    return &filetype is# 'kotlin'
+  endfunction
+
+  ""
+  " Reformat the current buffer using ktfmt, only targeting {ranges}.
+  function l:formatter.FormatRange(startline, endline) abort
+    " Split the command on spaces, except when there's a proceeding \
+    let l:cmd = split(s:plugin.Flag('ktfmt_executable'), '\\\@<! ')
+    try
+      " TODO(tstone) Switch to using --lines once that arg is added, see
+      " https://github.com/facebookincubator/ktfmt/issues/218
+      call codefmt#formatterhelpers#AttemptFakeRangeFormatting(
+          \ a:startline, a:endline, l:cmd)
+    catch /ERROR(ShellError):/
+      " Parse all the errors and stick them in the quickfix list.
+      let l:errors = []
+      for l:line in split(v:exception, "\n")
+        let l:tokens = matchlist(l:line, '\C\v^<stdin>:(\d+):(\d+):\s*(.*)')
+        if !empty(l:tokens)
+          call add(l:errors, {
+              \ 'filename': @%,
+              \ 'lnum': l:tokens[1] + a:startline - 1,
+              \ 'col': l:tokens[2],
+              \ 'text': l:tokens[3]})
+        endif
+      endfor
+      if empty(l:errors)
+        " Couldn't parse ktfmt error format; display it all.
+        call maktaba#error#Shout('Error formatting range: %s', v:exception)
+      else
+        call setqflist(l:errors, 'r')
+        cc 1
+      endif
+    endtry
+  endfunction
+
+  return l:formatter
+endfunction
+
+

instant/flags.vim

@@ -102,6 +102,11 @@ call s:plugin.Flag('buildifier_executable', 'buildifier')
 " `java -jar /path/to/google-java`
 call s:plugin.Flag('google_java_executable', 'google-java-format')
 
+""
+" The path to the ktfmt executable.  Generally, this should have the form:
+" `java -jar /path/to/ktfmt-VERSION-jar-with-dependencies.jar`
+call s:plugin.Flag('ktfmt_executable', 'ktfmt')
+
 ""
 " Command line arguments to feed shfmt. Either a list or callable that
 " takes no args and returns a list with command line arguments. By default, uses

plugin/register.vim

@@ -65,6 +65,7 @@ call s:registry.AddExtension(codefmt#gofmt#GetFormatter())
 call s:registry.AddExtension(codefmt#googlejava#GetFormatter())
 call s:registry.AddExtension(codefmt#jsbeautify#GetFormatter())
 call s:registry.AddExtension(codefmt#prettier#GetFormatter())
+call s:registry.AddExtension(codefmt#ktfmt#GetFormatter())
 call s:registry.AddExtension(codefmt#luaformatterfiveone#GetFormatter())
 call s:registry.AddExtension(codefmt#nixpkgs_fmt#GetFormatter())
 call s:registry.AddExtension(codefmt#autopep8#GetFormatter())

vroom/ktfmt.vroom

@@ -0,0 +1,40 @@
+The built-in ktfmt formatter knows how to format Java BUILD files.  If you
+aren't familiar with basic codefmt usage yet, see main.vroom first.
+
+We'll set up codefmt and configure the vroom environment, then jump into some
+examples.
+
+  :source $VROOMDIR/setupvroom.vim
+
+  :let g:repeat_calls = []
+  :function FakeRepeat(...)<CR>
+  |  call add(g:repeat_calls, a:000)<CR>
+  :endfunction
+  :call maktaba#test#Override('repeat#set', 'FakeRepeat')
+
+  :call codefmt#SetWhetherToPerformIsAvailableChecksForTesting(0)
+
+
+The ktfmt formatter expects a ktfmt executable to be installed on your system.
+
+  % class Foo { public bar() : String { return "bar"; } }
+  :FormatCode ktfmt
+  ! ktfmt .*
+  $ class Foo {
+  $   public bar(): String {
+  $     return "bar"
+  $   }
+  $ }
+
+The name or path of the ktmft executable can be configured via the
+ktfmt_executable flag if the default of "ktmft" doesn't work.
+
+  :Glaive codefmt ktfmt_executable='java -jar /path/to/ktfmt.jar'
+  :FormatCode ktfmt
+  ! java -jar /path/to/ktfmt.jar .*
+  $ class Foo {
+  $   public bar(): String {
+  $     return "bar"
+  $   }
+  $ }
+  :Glaive codefmt ktfmt_executable='ktfmt'