From 653bb1be874cb43892e629d2363d905b1ec77ea2 Mon Sep 17 00:00:00 2001
From: Daniel Hahler <github@thequod.de>
Date: Sat, 24 Feb 2018 18:19:25 +0100
Subject: [PATCH] statusline: improve error handling/reporting (#1873)

---
 autoload/neomake/statusline.vim | 13 ++++++++++---
 tests/statusline.vader          |  8 +++++---
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/autoload/neomake/statusline.vim b/autoload/neomake/statusline.vim
index 91cb52c0c0..09e9bba23a 100644
--- a/autoload/neomake/statusline.vim
+++ b/autoload/neomake/statusline.vim
@@ -151,8 +151,7 @@ function! s:formatter._substitute(m) abort
         return self.args[a:m]
     endif
     if !has_key(self, a:m)
-        call neomake#utils#ErrorMessage(printf(
-                    \ 'Unknown statusline format: {{%s}}.', a:m))
+        let self.errors += [printf('Unknown statusline format: {{%s}}.', a:m)]
         return '{{'.a:m.'}}'
     endif
     try
@@ -168,7 +167,15 @@ function! s:formatter.format(f, args) abort
         return a:f
     endif
     let self.args = a:args
-    return substitute(a:f, '{{\(.\{-}\)}}', '\=self._substitute(submatch(1))', 'g')
+    let self.errors = []
+    let r = substitute(a:f, '{{\(.\{-}\)}}', '\=self._substitute(submatch(1))', 'g')
+    if !empty(self.errors)
+        call neomake#utils#ErrorMessage(printf(
+                    \ 'Error%s when formatting %s: %s',
+                    \ len(self.errors) > 1 ? 's' : '',
+                    \ string(a:f), join(self.errors, ', ')))
+    endif
+    return r
 endfunction
 
 
diff --git a/tests/statusline.vader b/tests/statusline.vader
index 5975ce997e..73cbf779b0 100644
--- a/tests/statusline.vader
+++ b/tests/statusline.vader
@@ -66,7 +66,7 @@ Execute (neomake#statusline#get_status):
   AssertEqual neomake#statusline#get_status(bufnr, {'format_loclist_unknown': '{{running_job_names}}'}), ''
   " {{running_jobs}} is only available with 'format_running' (internally).
   AssertEqual neomake#statusline#get_status(bufnr, {'format_loclist_unknown': '{{running_jobs}}'}), '{{running_jobs}}'
-  AssertNeomakeMessage 'Unknown statusline format: {{running_jobs}}.', 0
+  AssertNeomakeMessage "Error when formatting '{{running_jobs}}': Unknown statusline format: {{running_jobs}}.", 0
 
   call neomake#Make({'enabled_makers': [g:sleep_maker]})
   if neomake#has_async_support()
@@ -80,7 +80,7 @@ Execute (neomake#statusline#get_status):
     Assert neomake#statusline#get_status(bufnr, {'format_running': '{{running_jobs}}'}) =~# '\m^{''', '{{running_jobs}} is replaced in format_running'
 
     call neomake#statusline#get_status(bufnr(''), {'format_running': 'Neomake: {{does_not_exist}}'})
-    AssertNeomakeMessage 'Unknown statusline format: {{does_not_exist}}.', 0
+    AssertNeomakeMessage "Error when formatting 'Neomake: {{does_not_exist}}': Unknown statusline format: {{does_not_exist}}.", 0
     NeomakeTestsWaitForFinishedJobs
   else
     AssertEqual neomake#statusline#get_status(bufnr, {'format_running': '...'}), '%#NeomakeStatusGood#✓'
@@ -89,7 +89,9 @@ Execute (neomake#statusline#get_status):
   endif
 
   call neomake#statusline#get_status(bufnr(''), {'format_loclist_ok': 'Neomake: {{does_not_exist}}'})
-  AssertNeomakeMessage 'Unknown statusline format: {{does_not_exist}}.', 0
+  AssertNeomakeMessage "Error when formatting 'Neomake: {{does_not_exist}}': Unknown statusline format: {{does_not_exist}}.", 0
+  call neomake#statusline#get_status(bufnr(''), {'format_loclist_ok': '{{foo}} {{bar}}'})
+  AssertNeomakeMessage "Errors when formatting '{{foo}} {{bar}}': Unknown statusline format: {{foo}}., Unknown statusline format: {{bar}}.", 0
 
   AssertEqual neomake#statusline#get_status(bufnr, {}), '%#NeomakeStatusGood#✓'
   AssertEqual neomake#statusline#get(bufnr, {}), '%#NeomakeStatusGood#✓'