debug: add :GoDebugTestFunc

Closes fatih#2931

autoload/go/debug.vim

@@ -689,6 +689,15 @@ function! s:handleRPCResult(resp) abort
   endtry
 endfunction
 
+function! go#debug#TestFunc(...) abort
+  let l:test = go#util#TestName()
+  if l:test is ''
+    call go#util#Warn("vim-go: [debug] no test found immediate to cursor")
+    return
+  endif
+  call call('go#debug#Start', extend(['test', '.', '-test.run', printf('%s$', l:testname)], a:000))
+endfunction
+
 " Start the debug mode. The first argument is the package name to compile and
 " debug, anything else will be passed to the running program.
 function! go#debug#Start(mode, ...) abort
@@ -770,9 +779,9 @@ endfunction
 
 " s:package returns the import path of package name of a :GoDebug(Start|Test)
 " call as a list so that the package can be appended to a command list using
-" extend(). args is expected to be a (potentially empty_ list. The first
+" extend(). args is expected to be a (potentially empty) list. The first
 " element in args (if there are any) is expected to be a package path. An
-" emnpty list is returned when either args is an empty list or the import path
+" empty list is returned when either args is an empty list or the import path
 " cannot be determined.
 function! s:package(args)
   if len(a:args) == 0

autoload/go/test.vim

@@ -106,23 +106,11 @@ endfunction
 " Testfunc runs a single test that surrounds the current cursor position.
 " Arguments are passed to the `go test` command.
 function! go#test#Func(bang, ...) abort
-  " search flags legend (used only)
-  " 'b' search backward instead of forward
-  " 'c' accept a match at the cursor position
-  " 'n' do Not move the cursor
-  " 'W' don't wrap around the end of the file
-  "
-  " for the full list
-  " :help search
-  let test = search('func \(Test\|Example\)', "bcnW")
-
-  if test == 0
-    echo "vim-go: [test] no test found immediate to cursor"
+  let l:test = go#util#TestName()
+  if l:test is ''
+    call go#util#EchoWarning("[test] no test found immediate to cursor")
     return
-  end
-
-  let line = getline(test)
-  let name = split(split(line, " ")[1], "(")[0]
+  endif
   let args = [a:bang, 0, "-run", name . "$"]
 
   if a:0

autoload/go/util.vim

@@ -704,10 +704,28 @@ function! go#util#Chdir(dir) abort
   if !exists('*chdir')
     let l:olddir = getcwd()
     let cd = exists('*haslocaldir') && haslocaldir() ? 'lcd ' : 'cd '
-    execute cd . fnameescape(a:dir)
-    return l:olddir
-  endif
-  return chdir(a:dir)
+    execute cd . fnameescape(a:dir) return l:olddir endif return chdir(a:dir)
+  endfunction
+
+" go#util#TestName returns the name of the test function that preceeds the
+" cursor.
+function go#util#TestName() abort
+  " search flags legend (used only)
+  " 'b' search backward instead of forward
+  " 'c' accept a match at the cursor position
+  " 'n' do Not move the cursor
+  " 'W' don't wrap around the end of the file
+  "
+  " for the full list
+  " :help search
+  let l:line = search('func \(Test\|Example\)', "bcnW")
+
+  if l:line == 0
+    return ''
+  end
+
+  let l:decl = getline(l:line)
+  return split(split(l:decl, " ")[1], "(")[0]
 endfunction
 
 " restore Vi compatibility settings

doc/vim-go.txt

@@ -2321,6 +2321,14 @@ The rest of the commands and mappings become available after executing
     Use `-test.flag` to pass flags to `go test` when debugging a test; for
     example `-test.v` or `-test.run TestFoo`
 
+                                                            *:GoDebugTestFunc*
+:GoDebugTestFunc [expand]
+
+    Behaves the same as |:GoDebugTest| and implicitly adds `-test.run` to run
+    the nearest test or example function (i.e the nearest function declaration
+    that matches `func Test` or `func Example`) at or previous to the cursor.
+    Search will not wrap around when at the top of the file.
+
                                                              *:GoDebugRestart*
 :GoDebugRestart
 

ftplugin/go/commands.vim

@@ -107,6 +107,7 @@ command! -nargs=0 GoFillStruct call go#fillstruct#FillStruct()
 if !exists(':GoDebugStart')
   command! -nargs=* -complete=customlist,go#package#Complete GoDebugStart call go#debug#Start('debug', <f-args>)
   command! -nargs=* -complete=customlist,go#package#Complete GoDebugTest  call go#debug#Start('test', <f-args>)
+  command! -nargs=* GoDebugTestFunc  call go#debug#TestFunc(<f-args>)
   command! -nargs=1 GoDebugAttach call go#debug#Start('attach', <f-args>)
   command! -nargs=? GoDebugBreakpoint call go#debug#Breakpoint(<f-args>)
 endif