less_conversion.rb in bootstrap-sass-3.1.0.2

- old
+ new

@@ -1,13 +1,11 @@
 require_relative 'char_string_scanner'
 
-# This module transforms LESS into SCSS.
-# It is implemented via lots of string manipulation: scanning back and forwards for regexps and doing substitions.
-# Since it does not parse the LESS into an AST, bits of it may assume LESS to be formatted a certain way, and only limited,
-# static analysis can be performed. This approach has so far been mostly enough to automatically convert most all of twbs/bootstrap.
-# There is some bootstrap-specific to make up for lack of certain features in Sass 3.2 (recursion, mixin namespacing)
-# and vice versa in LESS (vararg mixins).
+# This is the script used to automatically convert all of twbs/bootstrap LESS to Sass.
+#
+# Most differences are fixed by regexps and other forms of string substitution.
+# There are Bootstrap-specific workarounds for the lack of parent selectors, recursion, mixin namespaces, extend within @media, etc in Sass 3.2.
 class Converter
   module LessConversion
     # Some regexps for matching bits of SCSS:
     SELECTOR_CHAR               = '\[\]$\w\-{}#,.:&>@'
     # 1 selector (the part before the {)
@@ -52,10 +50,11 @@
     end
 
     def process_stylesheet_assets
       log_status 'Processing stylesheets...'
       files = read_files('less', bootstrap_less_files)
+      save_to = @save_to[:scss]
 
       log_status '  Converting LESS files to Scss:'
       files.each do |name, file|
         log_processing name
         # apply common conversions
@@ -80,13 +79,11 @@
             # see https://github.com/twbs/bootstrap-sass/issues/518
             file = replace_all file, '$ratio, $ratio-y', '$scale-args'
 
             file = convert_grid_mixins file
           when 'responsive-utilities.less'
-            file = apply_mixin_parent_selector(file, '&\.(visible|hidden)')
-            file = apply_mixin_parent_selector(file, '(?<!&)\.(visible|hidden)')
-            file = replace_rules(file, '  @media') { |r| unindent(r, 2) }
+            file = apply_mixin_parent_selector file, '\.(?:visible|hidden)'
           when 'variables.less'
             file = insert_default_vars(file)
             file = unindent <<-SCSS + file, 14
               // a flag to toggle asset pipeline / compass integration
               // defaults to true if twbs-font-path function is present (no function => twbs-font-path('') parsed as string == right side)
@@ -120,15 +117,18 @@
             # .bg-primary will not get patched automatically as it includes an additional rule. fudge for now
             file = replace_all(file, "  @include bg-variant($brand-primary);\n}", "}\n@include bg-variant('.bg-primary', $brand-primary);")
         end
 
         name    = name.sub(/\.less$/, '.scss')
-        save_to = @save_to[:scss]
         path    = "#{save_to}/#{'_' unless name == 'bootstrap.scss'}#{name}"
         save_file(path, file)
         log_processed File.basename(path)
       end
+
+      # generate imports valid relative to both load path and file directory
+      save_file File.expand_path("#{save_to}/../bootstrap.scss"),
+                File.read("#{save_to}/bootstrap.scss").gsub(/ "/, ' "bootstrap/')
     end
 
     def bootstrap_less_files
       @bootstrap_less_files ||= get_paths_by_type('less', /\.less$/)
     end
@@ -296,11 +296,15 @@
       replace_rules(file, '^\s*@mixin\s*' + rule_sel) do |mxn_css|
         mxn_css.sub! /(?=@mixin)/, "// [converter] $parent hack\n"
         # insert param into mixin def
         mxn_css.sub!(/(@mixin [\w-]+)\(([\$\w\-,\s]*)\)/) { "#{$1}(#{param}#{', ' if $2 && !$2.empty?}#{$2})" }
         # wrap properties in #{$parent} { ... }
-        replace_properties(mxn_css) { |props| props.strip.empty? ? props : "  \#{#{param}} { #{props.strip} }\n  " }
+        replace_properties(mxn_css) { |props|
+          next props if props.strip.empty?
+          spacer = ' ' * indent_width(props)
+          "#{spacer}\#{#{param}} {\n#{indent(props.sub(/\s+\z/, ''), 2)}\n#{spacer}}"
+        }
         # change nested& rules to nested#{$parent}
         replace_rules(mxn_css, /.*&[ ,:]/) { |rule| replace_in_selector rule, /&/, "\#{#{param}}" }
       end
     end
 
@@ -334,20 +338,21 @@
     def apply_mixin_parent_selector(file, rule_sel)
       log_transform rule_sel
       replace_rules file, '\s*' + rule_sel, comments: false do |rule, rule_pos, css|
         body = unwrap_rule_block(rule.dup).strip
         next rule unless body =~ /^@include \w+/m || body =~ /^@media/ && body =~ /\{\s*@include/
-        rule =~ /(#{COMMENT_RE}*)([#{SELECTOR_CHAR}]+?)\s*#{RULE_OPEN_BRACE_RE}/
+        rule =~ /(#{COMMENT_RE}*)([#{SELECTOR_CHAR}\s*]+?)#{RULE_OPEN_BRACE_RE}/
         cmt, sel = $1, $2.strip
         # take one up selector chain if this is an &. selector
         if sel.start_with?('&')
           parent_sel = selector_for_pos(css, rule_pos.begin)
           sel        = parent_sel + sel[1..-1]
         end
         # unwrap, and replace @include
         unindent unwrap_rule_block(rule).gsub(/(@include [\w-]+)\(([\$\w\-,\s]*)\)/) {
-          "#{cmt}#{$1}('#{sel}'#{', ' if $2 && !$2.empty?}#{$2})"
+          args = $2
+          "#{cmt}#{$1}('#{sel.gsub(/\s+/, ' ')}'#{', ' if args && !args.empty?}#{args})"
         }
       end
     end
 
     # #gradient > { @mixin horizontal ... }
@@ -568,24 +573,13 @@
     # replace first level properties in the css with yields
     # replace_properties("a { color: white }") { |props| props.gsub 'white', 'red' }
     def replace_properties(css, &block)
       s = CharStringScanner.new(css)
       s.skip_until /#{RULE_OPEN_BRACE_RE}\n?/
-      prev_pos = s.pos
-      depth    = 0
-      pos      = []
-      while (b = s.scan_next(/#{SELECTOR_RE}#{RULE_OPEN_BRACE_RE}|#{RULE_CLOSE_BRACE_RE}/m))
-        s_pos = s.pos
-        depth += (b == '}' ? -1 : +1)
-        if depth == 1
-          if b == '}'
-            prev_pos = s_pos
-          else
-            pos << (prev_pos .. s_pos - b.length - 1)
-          end
-        end
-      end
-      replace_substrings_at css, pos, &block
+      from = s.pos
+      m = s.scan_next(/\s*#{SELECTOR_RE}#{RULE_OPEN_BRACE_RE}/) || s.scan_next(/\s*#{RULE_CLOSE_BRACE_RE}/)
+      to = s.pos - m.length - 1
+      replace_substrings_at css, [(from .. to)], &block
     end
 
 
     # immediate selector of css at pos
     def selector_for_pos(css, pos, depth = -1)