fix regression involving min and max inside color functions

src/parse/args.rs

@@ -345,9 +345,9 @@ impl<'a> Parser<'a> {
                         None => return Err(("expected \")\".", span).into()),
                     }
                 }
-                Some(..) => {
+                Some(c) => {
                     value?;
-                    unreachable!()
+                    unreachable!("{:?}", c)
                 }
                 None => return Err(("expected \")\".", span).into()),
             }

src/parse/value/css_function.rs

@@ -240,6 +240,8 @@ impl<'a> Parser<'a> {
                 ')' => {
                     self.toks.advance_cursor();
                     buf.push(')');
+                    // todo: https://github.com/foresterre/peekmore/issues/38
+                    self.toks.peek();
                     return Ok(Some(buf));
                 }
                 '+' | '-' | '*' | '/' => {

src/parse/value/parse.rs

@@ -268,25 +268,10 @@ impl<'a> Parser<'a> {
         if let Some(Token { kind: '(', .. }) = self.toks.peek() {
             self.toks.next();
 
-            if lower == "min" {
+            if lower == "min" || lower == "max" {
-                match self.try_parse_min_max("min", true)? {
+                match self.try_parse_min_max(&lower, true)? {
                     Some(val) => {
                         self.toks.truncate_iterator_to_cursor();
-                        self.toks.next();
-                        return Ok(IntermediateValue::Value(HigherIntermediateValue::Literal(
-                            Value::String(val, QuoteKind::None),
-                        ))
-                        .span(span));
-                    }
-                    None => {
-                        self.toks.reset_cursor();
-                    }
-                }
-            } else if lower == "max" {
-                match self.try_parse_min_max("max", true)? {
-                    Some(val) => {
-                        self.toks.truncate_iterator_to_cursor();
-                        self.toks.next();
                         return Ok(IntermediateValue::Value(HigherIntermediateValue::Literal(
                             Value::String(val, QuoteKind::None),
                         ))

tests/color.rs

@@ -674,3 +674,9 @@ error!(
     alpha_filter_invalid_non_alphabetic_start,
     "a {\n  color: alpha(1=a);\n}\n", "Error: $color: 1=a is not a color."
 );
+// todo: we need many more of these tests
+test!(
+    rgba_special_fn_4th_arg_max,
+    "a {\n  color: rgba(1 2 max(3, 3));\n}\n",
+    "a {\n  color: rgba(1, 2, max(3, 3));\n}\n"
+);