Add coffee_indent_keep_current (#98)

Readme.md

@@ -380,6 +380,23 @@ This is the full list of configuration variables available, with example
 settings and default values. Use these in your vimrc to control the default
 behavior.
 
+#### coffee\_indent\_keep\_current
+
+By default, the indent function matches the indent of the previous line if it
+doesn't find a reason to indent or outdent. To change this behavior so it
+instead keeps the [current indent of the cursor][98], use
+
+    let coffee_indent_keep_current = 1
+
+[98]: https://github.com/kchmck/vim-coffee-script/pull/98
+
+*Default*: `unlet coffee_indent_keep_current`
+
+Note that if you change this after a coffee file has been loaded, you'll have to
+reload the indent script for the change to take effect:
+
+    unlet b:did_indent | runtime indent/coffee.vim
+
 #### coffee\_compiler
 
 Path to the `coffee` executable used by the `Coffee` commands:

indent/coffee.vim

@@ -15,6 +15,14 @@ setlocal indentexpr=GetCoffeeIndent(v:lnum)
 " indented or outdented.
 setlocal indentkeys+=0],0),0.,=else,=when,=catch,=finally
 
+" If no indenting or outdenting is needed, either keep the indent of the cursor
+" or match the indent of the previous line.
+if exists('g:coffee_indent_keep_current')
+  let s:DEFAULT_LEVEL = '-1'
+else
+  let s:DEFAULT_LEVEL = 'previndent'
+endif
+
 " Only define the function once.
 if exists('*GetCoffeeIndent')
   finish
@@ -345,7 +353,6 @@ function! GetCoffeeIndent(curlinenum)
     endif
   endif
 
-  " If no indent or outdent is needed, keep the indent level of the previous
-  " line.
-  return previndent
+  " No indenting or outdenting is needed so use the default policy.
+  exec 'return' s:DEFAULT_LEVEL
 endfunction