add go build for build errors (#180)

* add go build for build errors

* Add go build to doc and README

* Improvement for Go build

Go build works on package level, so copy over the other files
that belong to the same package to the temp folder as well.

* revert back to simple go build

* change gobuild script var name

README.md

@@ -61,7 +61,7 @@ name. That seems to be the fairest way to arrange this table.
 | Elixir | [credo](https://github.com/rrrene/credo) |
 | Elm | [elm-make](https://github.com/elm-lang/elm-make) |
 | Fortran | [gcc](https://gcc.gnu.org/) |
-| Go | [gofmt -e](https://golang.org/cmd/gofmt/), [go vet](https://golang.org/cmd/vet/), [golint](https://godoc.org/github.com/golang/lint) |
+| Go | [gofmt -e](https://golang.org/cmd/gofmt/), [go vet](https://golang.org/cmd/vet/), [golint](https://godoc.org/github.com/golang/lint), [go build](https://golang.org/cmd/go/) |
 | Haskell | [ghc](https://www.haskell.org/ghc/), [hlint](https://hackage.haskell.org/package/hlint) |
 | HTML | [HTMLHint](http://htmlhint.com/), [tidy](http://www.html-tidy.org/) |
 | JavaScript | [eslint](http://eslint.org/), [jscs](http://jscs.info/), [jshint](http://jshint.com/), [FlowType](https://flowtype.org/) |

ale_linters/go/gobuild.vim

@@ -0,0 +1,17 @@
+" Author: dzhou121 <dzhou121@gmail.com>
+" Description: go build for Go files
+
+function! s:FindGobuildScript() abort
+    return g:ale#util#stdin_wrapper . ' .go go build'
+endfunction
+
+let g:ale#util#gobuild_script =
+\   get(g:, 'ale_go_gobuild_script', s:FindGobuildScript())
+
+call ale#linter#Define('go', {
+\   'name': 'go build',
+\   'output_stream': 'stderr',
+\   'executable': 'go',
+\   'command': g:ale#util#gobuild_script,
+\   'callback': 'ale#handlers#HandleUnixFormatAsError',
+\})

doc/ale.txt

@@ -73,7 +73,7 @@ The following languages and tools are supported.
 * Elixir: 'credo'
 * Elm: 'elm-make'
 * Fortran: 'gcc'
-* Go: 'gofmt -e', 'go vet', 'golint'
+* Go: 'gofmt -e', 'go vet', 'golint', 'go build'
 * Haskell: 'ghc', 'hlint'
 * HTML: 'HTMLHint', 'tidy'
 * JavaScript: 'eslint', 'jscs', 'jshint', 'flow'