Echo string format (#76)

* Implement an option to configure the echoed message, #48

Via `g:ale_echo_msg_format` where:
- `%s` is the error message itself
- `%linter%` is the linter name
- `%severity` is the severity type

e.g
let g:ale_echo_msg_fomat = '[%linter%] [%severity%] %s'

* Add new options for defining the string used for errors in echoed
message

`g:ale_echo_msg_error_str` and `g:ale_echo_msg_warning_str`

* Change text output of some linters

Now that the echoed message can be customized, no need to add the type
to the text variable.

* Update README & documentation file

* Fix some typos
* Sort the table of options alphabetically (except echo_msg_x_str options)

* Added echo warning str option to the doc

7 files changed, 99 insertions, 11 deletions

diff --git a/README.md b/README.md
index a628e9e3..d142f400 100644
--- a/README.md
+++ b/README.md
@@ -76,20 +76,23 @@ vimrc file for all given linters is as follows:
 
 | Option | Description | Default |
 | ------ | ----------- | ------- |
-| `g:ale_linters` | a dictionary of linters to whitelist | _not set_ |
-| `g:ale_lint_on_text_changed` | lint while typing  | `1` |
+| `g:ale_echo_cursor` | echo errors when the cursor is over them | `1` |
+| `g:ale_echo_msg_format` | string format to use for the echoed message | `'%s'` |
+| `g:ale_echo_msg_error_str` | string used for error severity in echoed message | `'Error'` |
+| `g:ale_echo_msg_warning_str` | string used for warning severity in echoed message | `'Warning'` |
 | `g:ale_lint_delay` | milliseconds to wait before linting | `200` |
+| `g:ale_linters` | a dictionary of linters to whitelist | _not set_ |
 | `g:ale_lint_on_enter` | lint when opening a file  | `1` |
 | `g:ale_lint_on_save` | lint when saving a file  | `0` |
+| `g:ale_lint_on_text_changed` | lint while typing  | `1` |
 | `g:ale_set_loclist` | set the loclist with errors | `1` |
 | `g:ale_set_signs` | set gutter signs with error markers | `has('signs')` |
 | `g:ale_sign_column_always` | always show the sign gutter | `0` |
 | `g:ale_sign_error` | the text to use for errors in the gutter | `'>>'` |
-| `g:ale_sign_warning` | the text to use for warnings in the gutter | `'--'` |
 | `g:ale_sign_offset` | an offset for sign ids | `1000000` |
-| `g:ale_echo_cursor` | echo errors when the cursor is over them | `1` |
+| `g:ale_sign_warning` | the text to use for warnings in the gutter | `'--'` |
+| `g:ale_statusline_format` | string format to use in statusline flag | `['%d error(s)', '%d warning(s)', 'OK']` |
 | `g:ale_warn_about_trailing_whitespace` | enable trailing whitespace warnings for some linters | `1` |
-| `g:ale_statusline_format` | String format to use in statusline flag | `['%d error(s)', '%d warning(s)', 'OK']` |
 
 ### Selecting Particular Linters
 
@@ -155,6 +158,30 @@ let g:ale_statusline_format = ['⨉ %d', '⚠ %d', '⬥ ok']
 ![Statusline with issues](img/issues.png)
 ![Statusline with no issues](img/no_issues.png)
 
+
+### Customize echoed message
+
+There are 3 global options that allow customizing the echoed message.
+
+- `g:ale_echo_msg_format` where:
+  * `%s` is the error message itself
+  * `%linter%` is the linter name
+  * `%severity` is the severity type
+- `g:ale_echo_msg_error_str` is the string used for error severity.
+- `g:ale_echo_msg_warning_str` is the string used for warning severity.
+
+So for example this:
+
+```vim
+let g:ale_echo_msg_error_str = 'E'
+let g:ale_echo_msg_error_str = 'W'
+let g:ale_echo_msg_fomat = '[%linter%] %s [%severity%]'
+```
+
+Will give you:
+
+![Echoed message](img/echo.png)
+
 ## Installation
 
 To install this plugin, you should use one of the following methods.
diff --git a/ale_linters/coffee/coffeelint.vim b/ale_linters/coffee/coffeelint.vim
index aba29c4a..972fa25d 100644
--- a/ale_linters/coffee/coffeelint.vim
+++ b/ale_linters/coffee/coffeelint.vim
@@ -27,7 +27,7 @@ function! ale_linters#coffee#coffeelint#Handle(buffer, lines)
         let line = l:match[1] + 0
         let column = 1
         let type = l:match[3] ==# 'error' ? 'E' : 'W'
-        let text = l:match[3] . ': ' . l:match[4]
+        let text = l:match[4]
 
         " vcol is needed to indicate that the column is a character
         call add(output, {
diff --git a/ale_linters/yaml/yamllint.vim b/ale_linters/yaml/yamllint.vim
index cb7ca4b9..92a4313d 100644
--- a/ale_linters/yaml/yamllint.vim
+++ b/ale_linters/yaml/yamllint.vim
@@ -23,7 +23,7 @@ function! ale_linters#yaml#yamllint#Handle(buffer, lines)
         let line = match[1] + 0
         let col = match[2] + 0
         let type = match[3]
-        let text = printf('[%s]%s', type, match[4])
+        let text = match[4]
 
         " vcol is Needed to indicate that the column is a character.
         call add(output, {
diff --git a/doc/ale.txt b/doc/ale.txt
index bdd2b801..ec2e8028 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -1,7 +1,7 @@
-*ale.txt*  For Vim version 8.0.  Last change: 2016 October 7
+*ale.txt*  For Vim version 8.0.  Last change: 2016 October 10
 *ale*
 
-ALE - Asychronous Lint Engine
+ALE - Asynchronous Lint Engine
 
 ===============================================================================
 CONTENTS                                                         *ale-contents*
@@ -157,7 +157,7 @@ g:ale_set_signs                                               *g:ale_set_signs*
 
   When this option is set to `1`, the |sign| column will be populated with
   signs marking where errors and warnings appear in the file. The
-  'ALEErrorSign' and 'ALEWarningSign' highlight groups will be used to provide
+  `ALEErrorSign` and `ALEWarningSign` highlight groups will be used to provide
   highlighting for the signs. The text used for signs can be customised with
   the |g:ale_sign_error| and |g:ale_sign_warning| options.
 
@@ -216,6 +216,39 @@ g:ale_echo_cursor                                           *g:ale_echo_cursor*
   error at a column nearest to the cursor when the cursor is resting on a line
   which contains a warning or error. This option can be set to `0` to disable
   this behaviour.
+  The format of the message can be customizable in |g:ale_echo_msg_format|.
+
+
+g:ale_echo_msg_format                                    *g:ale_echo_msg_format*
+
+  Type: |String|
+  Default: `%s`
+
+  This variable defines the format of the echoed message. The `%s` is the
+  error message itself, and it can contain the following handlers:
+  - `%linter%` for linter's name
+  - `%severity%` for the type of severity
+  Note |`g:ale_echo_cursor`| should be setted to 1
+
+
+g:ale_echo_msg_error_str                              *g:ale_echo_msg_error_str*
+
+  Type: |String|
+  Default: `Error`
+
+  The string used for error severity in the echoed message.
+  Note |`g:ale_echo_cursor`| should be setted to 1
+  Note |`g:ale_echo_msg_format`| should contain the `%severity%` handler
+
+
+g:ale_echo_msg_warning_str                          *g:ale_echo_msg_warning_str*
+
+  Type: |String|
+  Default: `Warning`
+
+  The string used for warning severity in the echoed message.
+  Note |`g:ale_echo_cursor`| should be setted to 1
+  Note |`g:ale_echo_msg_format`| should contain the `%severity%` handler
 
 
 g:ale_warn_about_trailing_whitespace     *g:ale_warn_about_trailing_whitespace*
diff --git a/img/echo.png b/img/echo.png
new file mode 100644
index 00000000..671a66b2
--- /dev/null
+++ b/img/echo.png
diff --git a/plugin/ale/aaflags.vim b/plugin/ale/aaflags.vim
index 10d82128..f18dcc43 100644
--- a/plugin/ale/aaflags.vim
+++ b/plugin/ale/aaflags.vim
@@ -48,3 +48,12 @@ let g:ale_sign_column_always = get(g:, 'ale_sign_column_always', 0)
 let g:ale_statusline_format = get(g:, 'ale_statusline_format', 
 \   ['%d error(s)', '%d warning(s)', 'OK']
 \)
+
+" 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')
+
+" Strings used for severity in the echoed message
+let g:ale_echo_msg_error_str = get(g:, 'ale_echo_msg_error_str', 'Error')
+let g:ale_echo_msg_warning_str = get(g:, 'ale_echo_msg_warning_str', 'Warning')
diff --git a/plugin/ale/cursor.vim b/plugin/ale/cursor.vim
index e0751a8c..24f1f183 100644
--- a/plugin/ale/cursor.vim
+++ b/plugin/ale/cursor.vim
@@ -7,6 +7,23 @@ endif
 
 let g:loaded_ale_cursor = 1
 
+" Return a formatted message according to g:ale_echo_msg_format variable
+function! s:GetMessage(linter, type, text) abort
+    let msg = g:ale_echo_msg_format
+    let type = a:type ==# 'E'
+    \   ? g:ale_echo_msg_error_str
+    \   : g:ale_echo_msg_warning_str
+    " Capitalize the 1st character
+    let text = toupper(a:text[0]) . a:text[1:-1]
+
+    " Replace handlers if they exist
+    for [k, v] in items({'linter': a:linter, 'severity': type})
+        let msg = substitute(msg, '\V%' . k . '%', v, '')
+    endfor
+
+    return printf(msg, text)
+endfunction
+
 " This function will perform a binary search to find a message from the
 " loclist to echo when the cursor moves.
 function! s:BinarySearch(loclist, line, column)
@@ -81,7 +98,9 @@ function! ale#cursor#EchoCursorWarning(...)
     let index = s:BinarySearch(loclist, pos[1], pos[2])
 
     if index >= 0
-        call ale#cursor#TruncatedEcho(loclist[index]['text'])
+        let l = loclist[index]
+        let msg = s:GetMessage(l.linter_name, l.type, l.text)
+        call ale#cursor#TruncatedEcho(msg)
     else
         echo
     endif