check global scope for functions as well

src/scope.rs

@@ -14,6 +14,13 @@ pub(crate) fn get_global_var(s: &str) -> SassResult<Value> {
     })
 }
 
+pub(crate) fn get_global_fn(s: &str) -> SassResult<Function> {
+    GLOBAL_SCOPE.with(|scope| match scope.borrow().functions().get(s) {
+        Some(v) => Ok(v.clone()),
+        None => Err("Undefined function.".into()),
+    })
+}
+
 pub(crate) fn insert_global_var(s: &str, v: Value) -> SassResult<Option<Value>> {
     GLOBAL_SCOPE.with(|scope| scope.borrow_mut().insert_var(s, v))
 }
@@ -39,6 +46,10 @@ impl Scope {
         &self.vars
     }
 
+    pub const fn functions(&self) -> &HashMap<String, Function> {
+        &self.functions
+    }
+
     pub fn get_var(&self, v: &str) -> SassResult<Value> {
         let name = &v.replace('_', "-");
         match self.vars.get(name) {
@@ -70,10 +81,11 @@ impl Scope {
         self.mixins.contains_key(&v.replace('_', "-"))
     }
 
-    pub fn get_fn(&self, v: &str) -> SassResult<&Function> {
-        match self.functions.get(&v.replace('_', "-")) {
-            Some(v) => Ok(v),
-            None => Err("Undefined function.".into()),
+    pub fn get_fn(&self, v: &str) -> SassResult<Function> {
+        let name = &v.replace('_', "-");
+        match self.functions.get(name) {
+            Some(v) => Ok(v.clone()),
+            None => get_global_fn(name),
         }
     }
 

tests/functions.rs

@@ -63,3 +63,8 @@ test!(
     "a {\n  @function foo() {\n    @return 3;\n  }\n}\nb {\n  color: foo();\n}\n",
     "b {\n  color: foo();\n}\n"
 );
+test!(
+    global_function_in_scope,
+    "@function f() {\n  @return g();\n}\n@function g() {\n  @return false;\n}\na {\n  color: f();\n  color: g();\n}\n",
+    "a {\n  color: false;\n  color: false;\n}\n"
+);