Merge pull request #2 from mboughaba/confirmation_feature

Implementation of Confirmation Feature

README.md

@@ -17,6 +17,7 @@ This plugin is capable of doing the following things for you:
 * Remove empty lines at the end of the file;
 
 By default the plugin does all of the above when you save a file, but this can be disabled to be able to execute clean-up on demand only.
+Additionally, The plugin can be configuration to request user confirmation before removing white-spaces.
 
 
 ## Instalation
@@ -72,9 +73,11 @@ This is fully tested and blazing fast but if you don't mind white-spaces in your
 Out of the box, this plugin will clean trailing white-space, fix mixed-indent and remove empty lines at the end of a file when the file is saved.
 In more technical details, there are two important functions `LessmessExecute` and `LessmessDisplayToggle`.
 
+
 ### Automagically remove all annoying white-spaces :heavy_check_mark:
 White-spaces removal `onsave` is enabled by default. Just save the buffer and the file is clean.
 
+
 ### Manually remove all annoying white-spaces
 First, to disable lessmess `onsave` make sure to include the configuration below in your `.vimrc`
 ```vim
@@ -85,13 +88,15 @@ To remove (on demand) trailing white-spaces, fix mixed-indent and remove newline
 LessmessExecute
 ```
 
+
 ### Simple white-spaces highlighting
 I personally don't see a need of white-space highlighting, if I know they will be removed when I save. Nevertheless, to toggle highlighting of hidden characters, use command below.
 ```vim
 LessmessDisplayToggle
 ```
 This is simply calling vim native toggle list, I highly believe that syntax highlighting for white-spaces is a bit overkill. So why not just use ViM built-in list.
 
+
 ### Configuration
 1. To Enable/disable Lessmess
 ```vim
@@ -114,18 +119,32 @@ aug end
 let g:disable_lessmess = 1
  ```
 
+
 ### Handy tool
 When **Lessmess is disabled**, white-spaces can be removed by calling `force` execute:
 ```vim
 LessmessForceExecute
 ```
 
+
 ### Checking plugin status
 To check status of the plugin one should call
 ```vim
 LessmessStatus
 ```
 
+
+# Advanced configuration
+1. Lessmess can be configured to request user's confirmation before removing white-space. To enable this feature following configuration need to be added to the user's `.vimrc`
+```vim
+let g:confirm_whitespace_removal = 1
+```
+**This feature is disabled by default.**
+
+Before execution, the plugin will ask something similar to: `White-spaces found in file, remove them? y/N: `, user then decides to apply `y` or skip `N` (default) white-space removal.
+Confirmation is done once per buffer, this means that the plugin will remember user's choice for a given buffer.
+
+
 ## Running tests
 check the setup in the test folder.
 ```shell

autoload/lessmess.vim

@@ -39,6 +39,17 @@ el
         let g:disable_lessmess = 0
     en
     "
+    " Plugin won't ask for confirmation unless configured to do so
+    " Once authorization is granted this will be the default for the current
+    " buffer
+    "
+    if !exists("g:confirm_whitespace_removal")
+        let g:confirm_whitespace_removal = 0
+    en
+    if !exists("b:confirmed_whitespace_removal")
+        let b:confirmed_whitespace_removal = 0
+    en
+    "
     "
     " Set the interval in which ViM will dirty check the file
     " this is triggered after idle
@@ -140,6 +151,34 @@ fun! s:isEditable()
     en
 endf
 
+"
+" Check if user confirms removal of whitespaces
+"
+fun! s:isRemovalConfirmed()
+    "
+    " If the user confirmed removal of whitespace for the current buffer
+    " we will remember his choice
+    "
+    if exists("b:confirmed_whitespace_removal") && b:confirmed_whitespace_removal
+        retu 1
+    en
+
+    "
+    " As user confirmation
+    "
+    let l:res = input('White-spaces found in file, remove them? y/N: ')
+    if l:res == 'y'
+        echomsg "OK! White-spaces will be removed for the current buffer"
+        let b:confirmed_whitespace_removal = 1
+        retu 1
+    el
+        let b:confirmed_whitespace_removal = 0
+        echomsg "Fine! White-space removal will be skipped for the current buffer"
+        retu 0
+    en
+    retu 0
+endf
+
 "
 " Dirty check
 "
@@ -186,18 +225,27 @@ fun! lessmess#LessmessExecute(force)
     try
         if a:force || s:contains_empty_lines || s:contains_trailing_whitespaces || s:contains_mixed_indent
 
-            "
             "
             " Do nothing if the user disabled the plugin for this specific
             " buffer
             if !a:force && exists("b:lessmess_disable_buffer")
                 retu
             en
-            " done.
+
+            "
+            " If configured, ask confirmation before removing white-spaces
+            if !a:force && g:confirm_whitespace_removal && !s:isRemovalConfirmed()
+                retu
+            en
+
+            " Let's remember where the cursor is
+            let l:save_cursor = getpos(".")
+
+            "
             " We should add it then only if there is something to be done?
             " Remove Empty lines at the end of file
             if a:force || s:contains_empty_lines > 0
-                :keepp %s#\($\n\s*\)\+\%$##e | norm!``
+                :keepp %s#\($\n\s*\)\+\%$##e
             en
 
             " Replace all sequences of white-space containing a
@@ -210,7 +258,7 @@ fun! lessmess#LessmessExecute(force)
                 "
                 "
                 " retab the whole file
-                sil retab | norm!``
+                sil retab
                 "
                 "
                 " restore paste option
@@ -219,9 +267,12 @@ fun! lessmess#LessmessExecute(force)
 
             " Remove Trailing white-space
             if a:force || s:contains_trailing_whitespaces > 0
-                :keepp %s/\s\+$//e | norm!``
+                :keepp %s/\s\+$//e
             en
         en
+
+        " Restore cursor position
+        cal setpos('.', l:save_cursor)
     cat
         echomsg 'lessmess: darn it'
         echomsg v:exception

doc/lessmess.txt

@@ -79,6 +79,10 @@ Lessmess is enabled by default.
 When plugin is disabled white-spaces removal can be forced using command:
 LessmessForceExecute
 
+To make the plugin ask for confirmation before removing white-spaces following
+configuration needs to be added
+let g:confirm_whitespace_removal = 1
+
 ==============================================================================
 3. Configuration~