vim-patch:9.1.0967: SpotBugs compiler setup can be further improved

Problem:  SpotBugs compiler can be further improved
Solution: Introduce event-driven primitives for SpotBugs
          (Aliaksei Budavei)

closes: vim/vim#16258

https://github.com/vim/vim/commit/2e252474c4df5018b9819d86ebb70bf3b1b1a1af

Co-authored-by: Aliaksei Budavei <0x000c70@gmail.com>

4 files changed, 170 insertions, 8 deletions

diff --git a/runtime/compiler/spotbugs.vim b/runtime/compiler/spotbugs.vim
index 10d164b6af..8ed45f8ee0 100644
--- a/runtime/compiler/spotbugs.vim
+++ b/runtime/compiler/spotbugs.vim
@@ -1,7 +1,7 @@
 " Vim compiler file
 " Compiler:     Spotbugs (Java static checker; needs javac compiled classes)
-" Maintainer:   @konfekt and @zzzyxwvut
-" Last Change:  2024 Dec 14
+" Maintainers:  @konfekt and @zzzyxwvut
+" Last Change:  2024 Dec 20
 
 if exists('g:current_compiler') || bufname() !~# '\.java\=$' || wordcount().chars < 9
   finish
diff --git a/runtime/doc/quickfix.txt b/runtime/doc/quickfix.txt
index e56de9c1b4..7aeb494437 100644
--- a/runtime/doc/quickfix.txt
+++ b/runtime/doc/quickfix.txt
@@ -1410,6 +1410,70 @@ of |:make|, and assigning its |Funcref| to the selected key.  For example:
 			\ function('GenericPostCompilerCommand'),
 	\ }
 
+When "PostCompilerAction" is available, "PostCompilerActionExecutor" is also
+supported.  Its value must be a Funcref pointing to a function that always
+declares a single parameter of type string and decides whether |:execute| can
+be dispatched on its argument, containing a pending post-compiler action,
+after ascertaining the current status of |:cc| (or |:ll|): >vim
+
+	function! GenericPostCompilerActionExecutor(action) abort
+		try
+			cc
+		catch /\<E42:/
+			execute a:action
+		endtry
+	endfunction
+
+Complementary, some or all of the available "Pre*Action"s (or "*Pre*Command"s)
+may run `:doautocmd java_spotbugs_post User` in their implementations before
+|:make| (or its equivalent) to define a once-only |ShellCmdPost| `:autocmd`
+that will arrange for "PostCompilerActionExecutor" to be invoked; and then run
+`:doautocmd java_spotbugs_post ShellCmdPost` to consume this event: >vim
+
+	function! GenericPreCompilerCommand(arguments) abort
+		if !exists('g:spotbugs_compilation_done')
+			doautocmd java_spotbugs_post User
+			execute 'make ' . a:arguments
+			" only run doautocmd when :make was synchronous
+			" see note below
+			doautocmd java_spotbugs_post ShellCmdPost " XXX: (a)
+			let g:spotbugs_compilation_done = 1
+		else
+			cc
+		endif
+	endfunction
+
+	function! GenericPreCompilerTestCommand(arguments) abort
+		if !exists('g:spotbugs_test_compilation_done')
+			doautocmd java_spotbugs_post User
+			execute 'make ' . a:arguments
+			" only run doautocmd when :make was synchronous
+			" see note below
+			doautocmd java_spotbugs_post ShellCmdPost " XXX: (b)
+			let g:spotbugs_test_compilation_done = 1
+		else
+			cc
+		endif
+	endfunction
+
+	let g:spotbugs_properties = {
+		\ 'compiler':		'maven',
+		\ 'DefaultPreCompilerCommand':
+			\ function('GenericPreCompilerCommand'),
+		\ 'DefaultPreCompilerTestCommand':
+			\ function('GenericPreCompilerTestCommand'),
+		\ 'PostCompilerActionExecutor':
+			\ function('GenericPostCompilerActionExecutor'),
+	\ }
+
+If a command equivalent of `:make` is capable of asynchronous execution and
+consuming `ShellCmdPost` events, `:doautocmd java_spotbugs_post ShellCmdPost`
+must be removed from such "*Action" (or "*Command") implementations (i.e. the
+lines `(a)` and `(b)` in the listed examples) to retain a sequential order for
+non-blocking execution, and any notification (see below) must be suppressed.
+A `ShellCmdPost` `:autocmd` can be associated with any |:augroup| by assigning
+its name to the "augroupForPostCompilerAction" key.
+
 When default actions are not suited to a desired workflow, proceed by writing
 arbitrary functions yourself and matching their Funcrefs to the supported
 keys: "PreCompilerAction", "PreCompilerTestAction", and "PostCompilerAction".
diff --git a/runtime/ftplugin/java.vim b/runtime/ftplugin/java.vim
index 0fa773335d..cfd25bce6c 100644
--- a/runtime/ftplugin/java.vim
+++ b/runtime/ftplugin/java.vim
@@ -3,7 +3,7 @@
 " Maintainer:		Aliaksei Budavei <0x000c70 AT gmail DOT com>
 " Former Maintainer:	Dan Sharp
 " Repository:		https://github.com/zzzyxwvut/java-vim.git
-" Last Change:		2024 Dec 16
+" Last Change:		2024 Dec 25
 "			2024 Jan 14 by Vim Project (browsefilter)
 "			2024 May 23 by Riley Bruins <ribru17@gmail.com> ('commentstring')
 
@@ -113,7 +113,7 @@ if (!empty(get(g:, 'spotbugs_properties', {})) ||
     endfunction
 
     " Work around ":bar"s and ":autocmd"s.
-    function! s:ExecuteActionOnce(cleanup_cmd, action_cmd) abort
+    function! JavaFileTypeExecuteActionOnce(cleanup_cmd, action_cmd) abort
 	try
 	    execute a:cleanup_cmd
 	finally
@@ -285,7 +285,7 @@ if (!empty(get(g:, 'spotbugs_properties', {})) ||
 	for s:action in s:actions
 	    if has_key(s:action, 'once')
 		execute printf('autocmd java_spotbugs %s <buffer> ' .
-			\ 'call s:ExecuteActionOnce(%s, %s)',
+			\ 'call JavaFileTypeExecuteActionOnce(%s, %s)',
 		    \ s:action.event,
 		    \ string(printf('autocmd! java_spotbugs %s <buffer>',
 			\ s:action.event)),
@@ -297,7 +297,41 @@ if (!empty(get(g:, 'spotbugs_properties', {})) ||
 	    endif
 	endfor
 
-	unlet! s:action s:actions s:idx s:dispatcher
+	if s:SpotBugsHasProperty('PostCompilerActionExecutor') &&
+		\ (s:request == 7 || s:request == 6 ||
+		\ s:request == 5 || s:request == 4)
+	    let s:augroup = s:SpotBugsGetProperty(
+		\ 'augroupForPostCompilerAction',
+		\ 'java_spotbugs_post')
+	    let s:augroup = !empty(s:augroup) ? s:augroup : 'java_spotbugs_post'
+
+	    for s:candidate in ['java_spotbugs_post', s:augroup]
+		if !exists("#" . s:candidate)
+		    execute printf('augroup %s | augroup END', s:candidate)
+		endif
+	    endfor
+
+	    silent! autocmd! java_spotbugs_post User <buffer>
+
+	    " Define a User ":autocmd" to define a once-only ShellCmdPost
+	    " ":autocmd" that will invoke "PostCompilerActionExecutor" and let
+	    " it decide whether to proceed with ":compiler spotbugs" etc.; and
+	    " seek explicit synchronisation with ":doautocmd ShellCmdPost" by
+	    " omitting "nested" for "java_spotbugs_post" and "java_spotbugs".
+	    execute printf('autocmd java_spotbugs_post User <buffer> ' .
+				\ 'call JavaFileTypeExecuteActionOnce(%s, %s)',
+		\ string(printf('autocmd! %s ShellCmdPost <buffer>', s:augroup)),
+		\ string(printf('autocmd %s ShellCmdPost <buffer> ' .
+				\ 'call JavaFileTypeExecuteActionOnce(%s, %s)',
+		    \ s:augroup,
+		    \ string(printf('autocmd! %s ShellCmdPost <buffer>', s:augroup)),
+		    \ string(printf('call call(%s, [%s])',
+			\ string(s:SpotBugsGetProperties().PostCompilerActionExecutor),
+			\ string(printf('compiler spotbugs | call call(%s, [])',
+			    \ string(s:SpotBugsGetProperties().PostCompilerAction))))))))
+	endif
+
+	unlet! s:candidate s:augroup s:action s:actions s:idx s:dispatcher
     endif
 
     delfunction s:SpotBugsGetProperties
@@ -310,9 +344,11 @@ function! JavaFileTypeCleanUp() abort
     setlocal suffixes< suffixesadd< formatoptions< comments< commentstring< path< includeexpr<
     unlet! b:browsefilter
 
-    " The concatenated removals may be misparsed as a User autocmd.
+    " The concatenated ":autocmd" removals may be misparsed as an ":autocmd".
+    " A _once-only_ ShellCmdPost ":autocmd" is always a call-site definition.
     silent! autocmd! java_spotbugs User <buffer>
     silent! autocmd! java_spotbugs Syntax <buffer>
+    silent! autocmd! java_spotbugs_post User <buffer>
 endfunction
 
 " Undo the stuff we changed.
diff --git a/test/old/testdir/test_compiler.vim b/test/old/testdir/test_compiler.vim
index e6d5e57824..f9e7bf042d 100644
--- a/test/old/testdir/test_compiler.vim
+++ b/test/old/testdir/test_compiler.vim
@@ -399,12 +399,22 @@ func Test_compiler_spotbugs_properties()
   endfunc
   defer execute('delfunction g:SpotBugsPostCommand')
 
+  func! g:SpotBugsPostCompilerActionExecutor(action) abort
+    try
+      " XXX: Notify the spotbugs compiler about success or failure.
+      cc
+    catch /\<E42:/
+      execute a:action
+    endtry
+  endfunc
+  defer execute('delfunction g:SpotBugsPostCompilerActionExecutor')
+
   " TEST INTEGRATION WITH A SUPPORTED COMPILER PLUGIN.
   if filereadable($VIMRUNTIME .. '/compiler/maven.vim')
     if !executable('mvn')
       if has('win32')
         " This is what ":help executable()" suggests.
-        call writefile([], 'Xspotbugs/mvn.exe')
+        call writefile([], 'Xspotbugs/mvn.cmd')
       else
         let $PATH = 'Xspotbugs:' .. $PATH
         call writefile([], 'Xspotbugs/mvn')
@@ -590,6 +600,8 @@ func Test_compiler_spotbugs_properties()
         \ 'DefaultPreCompilerTestCommand': function('g:SpotBugsPreTestCommand'),
         \ 'DefaultPreCompilerCommand': function('g:SpotBugsPreCommand'),
         \ 'DefaultPostCompilerCommand': function('g:SpotBugsPostCommand'),
+        \ 'PostCompilerActionExecutor': function('g:SpotBugsPostCompilerActionExecutor'),
+        \ 'augroupForPostCompilerAction': 'java_spotbugs_test',
         \ 'sourceDirPath': ['Xspotbugs/src'],
         \ 'classDirPath': ['Xspotbugs/src'],
         \ 'testSourceDirPath': ['tests'],
@@ -636,6 +648,56 @@ func Test_compiler_spotbugs_properties()
       call assert_match('^spotbugs\s', &l:makeprg)
     endif
 
+    setlocal makeprg=
+    let s:spotbugs_results.preActionDone = 0
+    let s:spotbugs_results.preTestActionOtherDone = 0
+    let s:spotbugs_results.preTestLocalActionDone = 0
+    let s:spotbugs_results.postActionDone = 0
+    let s:spotbugs_results.preCommandArguments = ''
+    let s:spotbugs_results.preTestCommandArguments = ''
+    let s:spotbugs_results.postCommandArguments = ''
+
+    " When "PostCompilerActionExecutor", "Pre*Action" and/or "Pre*TestAction",
+    " and "Post*Action" are available, "#java_spotbugs_post" must be defined.
+    call assert_true(exists('#java_spotbugs_post'))
+    call assert_true(exists('#java_spotbugs_post#User'))
+    call assert_false(exists('#java_spotbugs_post#ShellCmdPost'))
+    call assert_false(exists('#java_spotbugs_test#ShellCmdPost'))
+
+    " Re-link a Funcref on the fly.
+    func! g:SpotBugsPreTestCommand(arguments) abort
+      let s:spotbugs_results.preTestActionOtherDone = 1
+      let s:spotbugs_results.preTestCommandArguments = a:arguments
+      " Define a once-only ":autocmd" for "#java_spotbugs_test#ShellCmdPost".
+      doautocmd java_spotbugs_post User
+      " XXX: Do NOT use ":cc" to notify the spotbugs compiler about success or
+      " failure, and assume the transfer of control to a ShellCmdPost command.
+    endfunc
+
+    doautocmd java_spotbugs User
+    " No match: "test_file !~# 'Xspotbugs/src'".
+    call assert_false(s:spotbugs_results.preActionDone)
+    call assert_true(empty(s:spotbugs_results.preCommandArguments))
+    " A match: "test_file =~# 'tests'".
+    call assert_true(s:spotbugs_results.preTestActionOtherDone)
+    call assert_equal('test-compile', s:spotbugs_results.preTestCommandArguments)
+    " For a pre-match, no post-action (without ":cc") UNLESS a ShellCmdPost
+    " event is consumed whose command will invoke "PostCompilerActionExecutor"
+    " and the latter will accept a post-compiler action argument.
+    call assert_false(s:spotbugs_results.postActionDone)
+    call assert_true(exists('#java_spotbugs_test#ShellCmdPost'))
+    doautocmd ShellCmdPost
+    call assert_false(exists('#java_spotbugs_test#ShellCmdPost'))
+    call assert_true(s:spotbugs_results.postActionDone)
+    call assert_equal('%:S', s:spotbugs_results.postCommandArguments)
+
+    " With a match, confirm that ":compiler spotbugs" has run.
+    if has('win32')
+      call assert_match('^spotbugs\.bat\s', &l:makeprg)
+    else
+      call assert_match('^spotbugs\s', &l:makeprg)
+    endif
+
     bwipeout
     setlocal makeprg=
   endif