list-separator is comma for maps and arglists

src/builtin/functions/list.rs

@@ -70,6 +70,7 @@ pub(crate) fn list_separator(mut args: CallArgs, parser: &mut Parser<'_>) -> Sas
     Ok(Value::String(
         match args.get_err(0, "list")? {
             Value::List(_, sep, ..) => sep.name(),
+            Value::Map(..) | Value::ArgList(..) => ListSeparator::Comma.name(),
             _ => ListSeparator::Space.name(),
         }
         .to_owned(),

tests/list.rs

@@ -61,6 +61,27 @@ test!(
     "a {\n  color: list-separator(((a b, c d)));\n}\n",
     "a {\n  color: comma;\n}\n"
 );
+test!(
+    list_separator_map,
+    "a {\n  color: list-separator((a: b, c: d));\n}\n",
+    "a {\n  color: comma;\n}\n"
+);
+test!(
+    list_separator_arglist,
+    "@mixin foo($arg...) {
+        color: list-separator($arg);
+    }
+
+    a {
+        @include foo(1, 2, 3);
+    }",
+    "a {\n  color: comma;\n}\n"
+);
+test!(
+    list_separator_empty,
+    "a {\n  color: list-separator(());\n}\n",
+    "a {\n  color: space;\n}\n"
+);
 test!(
     set_nth_named_args,
     "a {\n  color: set-nth($list: 1 2 3, $n: 2, $value: foo);\n}\n",
@@ -127,11 +148,6 @@ test!(
     "a {\n  color: append((a, b), c, space);\n}\n",
     "a {\n  color: a b c;\n}\n"
 );
-test!(
-    list_separator_empty,
-    "a {\n  color: list-separator(());\n}\n",
-    "a {\n  color: space;\n}\n"
-);
 test!(
     append_empty,
     "a {\n  color: append((), a);\n}\n",