Partial support for slurpy named arguments.

6 files changed, 55 insertions, 6 deletions

diff --git a/scss/compiler.py b/scss/compiler.py
index 2394258..fa25e7e 100644
--- a/scss/compiler.py
+++ b/scss/compiler.py
@@ -30,11 +30,12 @@ from scss.rule import SassRule
 from scss.rule import UnparsedBlock
 from scss.selector import Selector
 from scss.source import SourceFile
-from scss.types import Number
+from scss.types import Arglist
 from scss.types import Boolean
-from scss.types import String
 from scss.types import List
 from scss.types import Null
+from scss.types import Number
+from scss.types import String
 from scss.types import Undefined
 from scss.types import Url
 from scss.util import dequote
@@ -518,10 +519,15 @@ class Compilation(object):
 
         if callee_argspec.slurp:
             # Slurpy var gets whatever is left
+            # TODO should preserve the order of extra kwargs
+            sass_kwargs = []
+            for key, value in kwargs.items():
+                sass_kwargs.append((String(key[1:]), value))
             callee_namespace.set_variable(
                 callee_argspec.slurp.name,
-                List(args, use_comma=True))
+                Arglist(args, sass_kwargs))
             args = []
+            kwargs = {}
         elif callee_argspec.inject:
             # Callee namespace gets all the extra kwargs whether declared or
             # not
@@ -595,6 +601,8 @@ class Compilation(object):
                         ancestry=rule.ancestry,
                         nested=rule.nested,
                     )
+                    # TODO supposed to throw an error if there's a slurpy arg
+                    # but keywords() is never called on it
                     try:
                         self.manage_children(_rule, scope)
                     except SassReturn as e:
diff --git a/scss/functions/core.py b/scss/functions/core.py
index 1f6d30a..1fc830b 100644
--- a/scss/functions/core.py
+++ b/scss/functions/core.py
@@ -11,7 +11,7 @@ import math
 from six.moves import xrange
 
 from scss.functions.library import FunctionLibrary
-from scss.types import Boolean, Color, List, Null, Number, String, Map, expect_type
+from scss.types import Arglist, Boolean, Color, List, Null, Number, String, Map, expect_type
 
 log = logging.getLogger(__name__)
 
@@ -783,6 +783,13 @@ def comparable(number1, number2):
         and left.unit_denom == right.unit_denom)
 
 
+@register('keywords', 1)
+def keywords(value):
+    """Extract named arguments, as a map, from an argument list."""
+    expect_type(value, Arglist)
+    return value.extract_keywords()
+
+
 # ------------------------------------------------------------------------------
 # Miscellaneous
 
diff --git a/scss/src/grammar/grammar.g b/scss/src/grammar/grammar.g
index 870822e..6ef9262 100644
--- a/scss/src/grammar/grammar.g
+++ b/scss/src/grammar/grammar.g
@@ -52,8 +52,8 @@ parser SassExpression:
     rule goal_argspec:  argspec END                 {{ return argspec }}
 
     # Arguments:
-    # Note that at the moment, named arguments and slurpy arguments appear to
-    # be incompatible.
+    # TODO should support multiple slurpies, and enforce (probably not in the
+    # parser) that positional args come first
     rule argspec:
         [
             argspec_items           {{ args, slurpy = argspec_items }}
diff --git a/scss/tests/files/general/slurpy-keyword-args.css b/scss/tests/files/general/slurpy-keyword-args.css
new file mode 100644
index 0000000..ce36647
--- /dev/null
+++ b/scss/tests/files/general/slurpy-keyword-args.css
@@ -0,0 +1,5 @@
+p {
+  left: 5px;
+  right: 10px;
+  leftovers: red, blue;
+}
diff --git a/scss/tests/files/general/slurpy-keyword-args.scss b/scss/tests/files/general/slurpy-keyword-args.scss
new file mode 100644
index 0000000..87f0b5e
--- /dev/null
+++ b/scss/tests/files/general/slurpy-keyword-args.scss
@@ -0,0 +1,12 @@
+@mixin accepts-basically-anything($args...) {
+    @each $key, $value in keywords($args) {
+        #{$key}: $value;
+    }
+    @if length($args) {
+        leftovers: $args;
+    }
+}
+
+p {
+    @include accepts-basically-anything(red, blue, $left: 5px, $right: 10px);
+}
diff --git a/scss/types.py b/scss/types.py
index 05973fe..5803b24 100644
--- a/scss/types.py
+++ b/scss/types.py
@@ -733,6 +733,23 @@ class List(Value):
         return List([-item for item in self], use_comma=self.use_comma)
 
 
+class Arglist(List):
+    """An argument list.  Acts mostly like a list, with keyword arguments sort
+    of tacked on separately, and only accessible via Python (or the Sass
+    `keywords` function).
+    """
+    sass_type_name = 'arglist'
+    keywords_retrieved = False
+
+    def __init__(self, args, kwargs):
+        self._kwargs = Map(kwargs)
+        super(Arglist, self).__init__(args, use_comma=True)
+
+    def extract_keywords(self):
+        self.keywords_retrieved = True
+        return self._kwargs
+
+
 def _constrain(value, lb=0, ub=1):
     """Helper for Color constructors.  Constrains a value to a range."""
     if value < lb: