[Sass] Modify the stack stuff so that warnings look like error messages.

lib/sass/environment.rb

@@ -23,8 +23,7 @@ def initialize(parent = nil)
       @vars = {}
       @mixins = {}
       @parent = parent
-      @stack = []
-      @ignore_parent_stack = false
+      @stack = [] unless parent
       set_var("important", Script::String.new("!important")) unless @parent
     end
 
@@ -36,7 +35,8 @@ def options
       @options || (parent && parent.options) || {}
     end
 
-    # Push lexical frame information onto the runtime stack.
+    # Push a new stack frame onto the mixin/include stack.
+    #
     # @param frame_info [{Symbol => Object}]
     #   Frame information has the following keys:
     #
@@ -49,40 +49,36 @@ def options
     #
     #   `:line`
     #   : The line of the file on which the lexical scope changed. Never nil.
+    def push_frame(frame_info)
+      if stack.last && stack.last[:prepared]
+        stack.last.delete(:prepared)
+        stack.last.merge!(frame_info)
+      else
+        stack.push(frame_info)
+      end
+    end
+
+    # Like \{#push\_frame}, but next time a stack frame is pushed,
+    # it will be merged with this frame.
     #
-    #   `:import`
-    #   : Set to `true` when the lexical scope is changing due to an import.
-    def push(frame_info)
-      @stack.push frame_info
+    # @param frame_info [{Symbol => Object}] Same as for \{#push\_frame}.
+    def prepare_frame(frame_info)
+      push_frame(frame_info.merge(:prepared => true))
     end
 
-    # Pop runtime frame information from the stack.
-    def pop
-      @stack.pop
+    # Pop a stack frame from the mixin/include stack.
+    def pop_frame
+      stack.pop if stack.last[:prepared]
+      stack.pop
     end
 
-    # A list of the runtime stack frame information
-    # The last element in the list was pushed onto the stack most recently.
+    # A list of stack frames in the mixin/include stack.
+    # The last element in the list is the most deeply-nested frame.
     #
     # @return [Array<{Symbol => Object}>] The stack frames,
     #   of the form passed to \{#push}.
     def stack
-      prev = (!@ignore_parent_stack && parent && parent.stack) || []
-      prev + @stack
-    end
-
-    # Temporarily assume the runtime stack that is passed in.
-    #
-    # @param stk [Array<{Symbol => Object}>] A call stack from another environment,
-    #   of the form returned by \{#stack}.
-    # @yield A block in which the stack is set to `stk`.
-    def with_stack(stk)
-      @stack, old_stack = stk, @stack
-      @ignore_parent_stack = true
-      yield self
-    ensure
-      @ignore_parent_stack = false
-      @stack = old_stack
+      @stack ||= @parent.stack
     end
 
     class << self

lib/sass/tree/import_node.rb

@@ -62,7 +62,7 @@ def _perform(environment)
       # @param environment [Sass::Environment] The lexical environment containing
       #   variable and mixin values
       def perform!(environment)
-        environment.push(:filename => @filename, :line => @line, :import => true)
+        environment.push_frame(:filename => @filename, :line => @line)
         root = Sass::Files.tree_for(full_filename, @options)
         @template = root.template
         self.children = root.children
@@ -72,7 +72,7 @@ def perform!(environment)
         e.add_backtrace(:filename => @filename, :line => @line)
         raise e
       ensure
-        environment.pop
+        environment.pop_frame
       end
 
       private

lib/sass/tree/mixin_node.rb

@@ -51,38 +51,37 @@ def _cssize(parent)
     # @see Sass::Tree
     def perform!(environment)
       original_env = environment
-      original_env.push(:filename => filename, :mixin => @name, :line => line)
+      original_env.push_frame(:filename => filename, :line => line)
+      original_env.prepare_frame(:mixin => @name)
       raise Sass::SyntaxError.new("Undefined mixin '#{@name}'.") unless mixin = environment.mixin(@name)
 
       raise Sass::SyntaxError.new(<<END.gsub("\n", "")) if mixin.args.size < @args.size
 Mixin #{@name} takes #{mixin.args.size} argument#{'s' if mixin.args.size != 1}
  but #{@args.size} #{@args.size == 1 ? 'was' : 'were'} passed.
 END
-
-      mixin.environment.with_stack(original_env.stack) do |mixin_env|
-        environment = mixin.args.zip(@args).
-          inject(Sass::Environment.new(mixin_env)) do |env, ((var, default), value)|
-          env.set_local_var(var.name,
-            if value
-              value.perform(environment)
-            elsif default
-              val = default.perform(env)
-              if default.context == :equals && val.is_a?(Sass::Script::String)
-                val = Sass::Script::String.new(val.value)
-              end
-              val
-            end)
-          raise Sass::SyntaxError.new("Mixin #{@name} is missing parameter #{var.inspect}.") unless env.var(var.name)
-          env
-        end
-        self.children = mixin.tree.map {|c| c.perform(environment)}.flatten
+      environment = mixin.args.zip(@args).
+        inject(Sass::Environment.new(mixin.environment)) do |env, ((var, default), value)|
+        env.set_local_var(var.name,
+          if value
+            value.perform(environment)
+          elsif default
+            val = default.perform(env)
+            if default.context == :equals && val.is_a?(Sass::Script::String)
+              val = Sass::Script::String.new(val.value)
+            end
+            val
+          end)
+        raise Sass::SyntaxError.new("Mixin #{@name} is missing parameter #{var.inspect}.") unless env.var(var.name)
+        env
       end
+
+      self.children = mixin.tree.map {|c| c.perform(environment)}.flatten
     rescue Sass::SyntaxError => e
       e.modify_backtrace(:mixin => @name, :line => @line)
       e.add_backtrace(:line => @line)
       raise e
     ensure
-      original_env.pop
+      original_env.pop_frame
     end
   end
 end

lib/sass/tree/warn_node.rb

@@ -21,25 +21,20 @@ def to_src(tabs, opts, fmt)
       # @param environment [Sass::Environment] The lexical environment containing
       #   variable and mixin values
       def _perform(environment)
-        environment.push(:filename => filename, :line => line)
+        environment.push_frame(:filename => filename, :line => line)
         res = @expr.perform(environment)
         res = res.value if res.is_a?(Sass::Script::String)
-        Haml::Util.haml_warn "WARNING: #{res}"
-        Haml::Util.enum_with_index(environment.stack.reverse).each do |entry, i|
-          where = "         "
-          if entry[:mixin]
-            where << "via '#{entry[:mixin]}' mixed in at line #{entry[:line]}"
-          elsif entry[:import]
-            where << "imported from line #{entry[:line]}"
-          else
-            where << "#{"issued" if i == 0} from line #{entry[:line]}"
-          end
-          where << " of #{entry[:filename] || "(sass)"}"
-          Haml::Util.haml_warn where
+        msg = "WARNING: #{res}\n"
+        environment.stack.reverse.each_with_index do |entry, i|
+          msg << "        #{i == 0 ? "on" : "from"} line #{entry[:line]}" <<
+            " of #{entry[:filename] || "an unknown file"}"
+          msg << ", in `#{entry[:mixin]}'" if entry[:mixin]
+          msg << "\n"
         end
+        Haml::Util.haml_warn msg
         []
       ensure
-        environment.pop
+        environment.pop_frame
       end
     end
   end

test/sass/engine_test.rb

@@ -1715,10 +1715,11 @@ def test_equals_properties_force_division
   def test_warn_directive
   expected_warning = <<EXPECTATION
 WARNING: this is a warning
-         issued from line 4 of test_warn_directive_inline.sass
+        on line 4 of test_warn_directive_inline.sass
+
 WARNING: this is a mixin warning
-         issued from line 2 of test_warn_directive_inline.sass
-         via 'foo' mixed in at line 7 of test_warn_directive_inline.sass
+        on line 2 of test_warn_directive_inline.sass, in `foo'
+        from line 7 of test_warn_directive_inline.sass
 EXPECTATION
     assert_warning expected_warning do
       assert_equal <<CSS, render(<<SASS)
@@ -1748,13 +1749,15 @@ def test_warn_directive_when_quiet
   def test_warn_with_imports
     expected_warning = <<WARN
 WARNING: In the main file
-         issued from line 1 of #{File.dirname(__FILE__)}/templates/warn.sass
+        on line 1 of #{File.dirname(__FILE__)}/templates/warn.sass
+
 WARNING: Imported
-         issued from line 1 of #{File.dirname(__FILE__)}/templates/warn_imported.sass
-         imported from line 2 of #{File.dirname(__FILE__)}/templates/warn.sass
+        on line 1 of #{File.dirname(__FILE__)}/templates/warn_imported.sass
+        from line 2 of #{File.dirname(__FILE__)}/templates/warn.sass
+
 WARNING: In an imported mixin
-         issued from line 4 of #{File.dirname(__FILE__)}/templates/warn_imported.sass
-         via 'emits-a-warning' mixed in at line 3 of #{File.dirname(__FILE__)}/templates/warn.sass
+        on line 4 of #{File.dirname(__FILE__)}/templates/warn_imported.sass, in `emits-a-warning'
+        from line 3 of #{File.dirname(__FILE__)}/templates/warn.sass
 WARN
     assert_warning expected_warning do
       renders_correctly "warn", :style => :compact, :load_paths => [File.dirname(__FILE__) + "/templates"]

test/sass/scss/scss_test.rb

@@ -116,10 +116,11 @@ def test_debug_directive
   def test_warn_directive
     expected_warning = <<EXPECTATION
 WARNING: this is a warning
-         issued from line 2 of test_warn_directive_inline.scss
+        on line 2 of test_warn_directive_inline.scss
+
 WARNING: this is a mixin
-         issued from line 1 of test_warn_directive_inline.scss
-         via 'foo' mixed in at line 3 of test_warn_directive_inline.scss
+        on line 1 of test_warn_directive_inline.scss, in `foo'
+        from line 3 of test_warn_directive_inline.scss
 EXPECTATION
     assert_warning expected_warning do
       assert_equal <<CSS, render(<<SCSS)