#852 Support formatting echo messages with error codes. No linters set the `code` key yet

5 files changed, 63 insertions, 32 deletions

diff --git a/autoload/ale/cursor.vim b/autoload/ale/cursor.vim
index c7c74c9b..7b848623 100644
--- a/autoload/ale/cursor.vim
+++ b/autoload/ale/cursor.vim
@@ -5,22 +5,27 @@ let s:cursor_timer = -1
 let s:last_pos = [0, 0, 0]
 
 " Return a formatted message according to g:ale_echo_msg_format variable
-function! s:GetMessage(linter, type, text) abort
+function! s:GetMessage(item) abort
     let l:msg = g:ale_echo_msg_format
     let l:severity = g:ale_echo_msg_warning_str
+    let l:code = get(a:item, 'code', '')
+    let l:code_repl = !empty(l:code) ? '\=submatch(1) . l:code . submatch(2)' : ''
 
-    if a:type is# 'E'
+    if a:item.type is# 'E'
         let l:severity = g:ale_echo_msg_error_str
-    elseif a:type is# 'I'
+    elseif a:item.type is# 'I'
         let l:severity = g:ale_echo_msg_info_str
     endif
 
-    " Replace handlers if they exist
-    for [l:k, l:v] in items({'linter': a:linter, 'severity': l:severity})
-        let l:msg = substitute(l:msg, '\V%' . l:k . '%', l:v, '')
-    endfor
+    " Replace special markers with certain information.
+    " \=l:variable is used to avoid escaping issues.
+    let l:msg = substitute(l:msg, '\V%severity%', '\=l:severity', 'g')
+    let l:msg = substitute(l:msg, '\V%linter%', '\=a:item.linter_name', 'g')
+    let l:msg = substitute(l:msg, '\v\%([^\%]*)code([^\%]*)\%', l:code_repl, 'g')
+    " Replace %s with the text.
+    let l:msg = substitute(l:msg, '\V%s', '\=a:item.text', 'g')
 
-    return printf(l:msg, a:text)
+    return l:msg
 endfunction
 
 function! s:EchoWithShortMess(setting, message) abort
@@ -91,7 +96,7 @@ function! s:EchoImpl() abort
     let [l:info, l:loc] = s:FindItemAtCursor()
 
     if !empty(l:loc)
-        let l:msg = s:GetMessage(l:loc.linter_name, l:loc.type, l:loc.text)
+        let l:msg = s:GetMessage(l:loc)
         call ale#cursor#TruncatedEcho(l:msg)
         let l:info.echoed = 1
     elseif get(l:info, 'echoed')
diff --git a/doc/ale.txt b/doc/ale.txt
index 5638a2c8..3a43685d 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -643,20 +643,27 @@ g:ale_echo_msg_error_str                             *g:ale_echo_msg_error_str*
 g:ale_echo_msg_format                                   *g:ale_echo_msg_format*
 
   Type: |String|
-  Default: `'%s'`
+  Default: `'%code: %%s'`
 
   This variable defines a message format for echoed messages. The following
   sequences of characters will be replaced.
 
-    `%s`         - will be replaced with the text for the problem
-    `%linter%`   - will be replaced with the name of the linter
-    `%severity%` - will be replaced withe severity of the problem
+    `%s`           - replaced with the text for the problem
+    `%...code...% `- replaced with the error code
+    `%linter%`     - replaced with the name of the linter
+    `%severity%`   - replaced withe severity of the problem
 
   The strings for `%severity%` can be configured with the following options.
 
     |g:ale_echo_msg_error_str|   - Defaults to `'Error'`
     |g:ale_echo_msg_warning_str| - Defaults to `'Warning'`
 
+  `%code%` is replaced with the error code, and replaced with an empty string
+  when there is no error code. Any extra characters between the percent signs
+  will be printed when an error code is present. For example, a message like
+  `(error code): message` will be printed for `'%(code): %%s'` and simply the
+  message will be printed when there is no code.
+
   |g:ale_echo_cursor| needs to be set to 1 for messages to be displayed.
 
 
diff --git a/plugin/ale.vim b/plugin/ale.vim
index c67e1de7..26d3c43d 100644
--- a/plugin/ale.vim
+++ b/plugin/ale.vim
@@ -148,10 +148,8 @@ let g:ale_sign_offset = get(g:, 'ale_sign_offset', 1000000)
 " This flag can be set to 1 to keep sign gutter always open
 let g:ale_sign_column_always = get(g:, 'ale_sign_column_always', 0)
 
-" String format for the echoed message
-" A %s is mandatory
-" It can contain 2 handlers: %linter%, %severity%
-let g:ale_echo_msg_format = get(g:, 'ale_echo_msg_format', '%s')
+" A string format for the echoed message
+let g:ale_echo_msg_format = get(g:, 'ale_echo_msg_format', '%code: %%s')
 
 " Strings used for severity in the echoed message
 let g:ale_echo_msg_error_str = get(g:, 'ale_echo_msg_error_str', 'Error')
diff --git a/test/test_ale_info.vader b/test/test_ale_info.vader
index ceb65af6..30237a3c 100644
--- a/test/test_ale_info.vader
+++ b/test/test_ale_info.vader
@@ -21,7 +21,7 @@ Before:
   \  '',
   \  'let g:ale_echo_cursor = 1',
   \  'let g:ale_echo_msg_error_str = ''Error''',
-  \  'let g:ale_echo_msg_format = ''%s''',
+  \  'let g:ale_echo_msg_format = ''%code: %%s''',
   \  'let g:ale_echo_msg_warning_str = ''Warning''',
   \  'let g:ale_enabled = 1',
   \  'let g:ale_fix_on_save = 0',
diff --git a/test/test_cursor_warnings.vader b/test/test_cursor_warnings.vader
index 20ccb157..dbcbe66e 100644
--- a/test/test_cursor_warnings.vader
+++ b/test/test_cursor_warnings.vader
@@ -12,8 +12,9 @@ Before:
   \       'linter_name': 'eslint',
   \       'nr': -1,
   \       'type': 'E',
-  \       'text': 'Missing semicolon. (semi)',
-  \       'detail': "Every statement should end with a semicolon\nsecond line"
+  \       'code': 'semi',
+  \       'text': 'Missing semicolon.',
+  \       'detail': "Every statement should end with a semicolon\nsecond line",
   \     },
   \     {
   \       'lnum': 1,
@@ -33,7 +34,8 @@ Before:
   \       'linter_name': 'eslint',
   \       'nr': -1,
   \       'type': 'W',
-  \       'text': 'Infix operators must be spaced. (space-infix-ops)'
+  \       'code': 'space-infix-ops',
+  \       'text': 'Infix operators must be spaced.',
   \     },
   \     {
   \       'lnum': 2,
@@ -43,7 +45,8 @@ Before:
   \       'linter_name': 'eslint',
   \       'nr': -1,
   \       'type': 'E',
-  \       'text': 'Missing radix parameter (radix)'
+  \       'code': 'radix',
+  \       'text': 'Missing radix parameter',
   \     },
   \     {
   \       'lnum': 3,
@@ -53,7 +56,7 @@ Before:
   \       'linter_name': 'eslint',
   \       'nr': -1,
   \       'type': 'E',
-  \       'text': 'lowercase error'
+  \       'text': 'lowercase error',
   \     },
   \   ],
   \ },
@@ -103,19 +106,19 @@ Execute(Messages should be shown for the correct lines):
   call cursor(1, 1)
   call ale#cursor#EchoCursorWarning()
 
-  AssertEqual 'Missing semicolon. (semi)', GetLastMessage()
+  AssertEqual 'semi: Missing semicolon.', GetLastMessage()
 
 Execute(Messages should be shown for earlier columns):
   call cursor(2, 1)
   call ale#cursor#EchoCursorWarning()
 
-  AssertEqual 'Infix operators must be spaced. (space-infix-ops)', GetLastMessage()
+  AssertEqual 'space-infix-ops: Infix operators must be spaced.', GetLastMessage()
 
 Execute(Messages should be shown for later columns):
   call cursor(2, 16)
   call ale#cursor#EchoCursorWarning()
 
-  AssertEqual 'Missing radix parameter (radix)', GetLastMessage()
+  AssertEqual 'radix: Missing radix parameter', GetLastMessage()
 
 Execute(The message at the cursor should be shown when linting ends):
   call cursor(1, 1)
@@ -124,13 +127,13 @@ Execute(The message at the cursor should be shown when linting ends):
   \ g:ale_buffer_info[bufnr('%')].loclist,
   \)
 
-  AssertEqual 'Missing semicolon. (semi)', GetLastMessage()
+  AssertEqual 'semi: Missing semicolon.', GetLastMessage()
 
 Execute(The message at the cursor should be shown on InsertLeave):
   call cursor(2, 9)
   doautocmd InsertLeave
 
-  AssertEqual 'Infix operators must be spaced. (space-infix-ops)', GetLastMessage()
+  AssertEqual 'space-infix-ops: Infix operators must be spaced.', GetLastMessage()
 
 Execute(ALEDetail should print 'detail' attributes):
   call cursor(1, 1)
@@ -148,7 +151,7 @@ Execute(ALEDetail should print regular 'text' attributes):
     ALEDetail
   redir END
 
-  AssertEqual "\nInfix operators must be spaced. (space-infix-ops)", g:output
+  AssertEqual "\nInfix operators must be spaced.", g:output
 
 Execute(ALEDetail should not capitlise cursor messages):
   call cursor(3, 1)
@@ -163,7 +166,7 @@ Execute(The linter name should be formatted into the message correctly):
   call ale#cursor#EchoCursorWarning()
 
   AssertEqual
-  \ 'eslint: Infix operators must be spaced. (space-infix-ops)',
+  \ 'eslint: Infix operators must be spaced.',
   \ GetLastMessage()
 
 Execute(The severity should be formatted into the message correctly):
@@ -173,15 +176,33 @@ Execute(The severity should be formatted into the message correctly):
   call ale#cursor#EchoCursorWarning()
 
   AssertEqual
-  \ 'Warning: Infix operators must be spaced. (space-infix-ops)',
+  \ 'Warning: Infix operators must be spaced.',
   \ GetLastMessage()
 
   call cursor(1, 10)
   call ale#cursor#EchoCursorWarning()
 
-  AssertEqual 'Error: Missing semicolon. (semi)', GetLastMessage()
+  AssertEqual 'Error: Missing semicolon.', GetLastMessage()
 
   call cursor(1, 14)
   call ale#cursor#EchoCursorWarning()
 
   AssertEqual 'Info: Some information', GetLastMessage()
+
+Execute(The %code% and %ifcode% should show the code and some text):
+  let g:ale_echo_msg_format = '%(code) %%s'
+
+  call cursor(2, 9)
+  call ale#cursor#EchoCursorWarning()
+
+  AssertEqual
+  \ '(space-infix-ops) Infix operators must be spaced.',
+  \ GetLastMessage()
+
+Execute(The %code% and %ifcode% should be removed when there's no code):
+  let g:ale_echo_msg_format = '%(code) %%s'
+
+  call cursor(1, 14)
+  call ale#cursor#EchoCursorWarning()
+
+  AssertEqual 'Some information', GetLastMessage()