Merge pull request #5 from inobulles/bugfix/double-scope-on-stack-whe…

…n-calling-on-instance

Fix double scope on stack when calling on instance

flamingo/call.h

@@ -83,8 +83,10 @@ static int call(
 	flamingo_val_t** rv,
 	flamingo_arg_list_t* args
 ) {
+	// Note about calling functions on instances: we don't actually need to add its scope to the environment, because the environment on its callable already has that scope on the scope stack.
+	// If we ever need to know whether or not we're calling on an instance, the following check can be used: accessed_val != NULL && accessed_val->kind == FLAMINGO_VAL_KIND_INST
+
 	bool const is_class = callable->fn.kind == FLAMINGO_FN_KIND_CLASS;
-	bool const on_inst = accessed_val != NULL && accessed_val->kind == FLAMINGO_VAL_KIND_INST;
 	bool const is_extern = callable->fn.kind == FLAMINGO_FN_KIND_EXTERN;
 	bool const is_ptm = callable->fn.kind == FLAMINGO_FN_KIND_PTM;
 
@@ -107,19 +109,15 @@ static int call(
 	// Switch context's current environment to the one closed over by the function.
 
 	flamingo_env_t* const prev_env = flamingo->env;
-	flamingo->env = callable->fn.env == NULL ? prev_env : callable->fn.env;
-
-	// If calling on an instance, add that instance's scope to the scope stack.
-	// We do this before the arguments scope because we want parameters to shadow stuff in the instance's scope.
 
-	if (on_inst) {
-		env_gently_attach_scope(flamingo->env, accessed_val->inst.scope);
+	if (callable->fn.env != NULL) {
+		flamingo->env = callable->fn.env;
 	}
 
 	// Create a new scope for the function for the argument assignments.
 	// It's important to set 'scope->class_scope' to false for functions as new scopes will copy the 'class_scope' property from their parents otherwise.
 
-	flamingo_scope_t* scope = env_push_scope(flamingo->env);
+	flamingo_scope_t* const scope = env_push_scope(flamingo->env);
 	scope->class_scope = is_class;
 
 	if (is_ptm) {
@@ -193,10 +191,6 @@ static int call(
 
 	env_pop_scope(flamingo->env);
 
-	if (on_inst) {
-		env_gently_detach_scope(flamingo->env);
-	}
-
 	flamingo->src = prev_src;
 	flamingo->src_size = prev_src_size;
 

flamingo/env.h

@@ -50,6 +50,8 @@ static flamingo_scope_t* env_cur_scope(flamingo_env_t* env) {
 }
 
 static void env_gently_attach_scope(flamingo_env_t* env, flamingo_scope_t* scope) {
+	assert(env->scope_stack_size == 0 || env->scope_stack[env->scope_stack_size - 1] != scope);
+
 	env->scope_stack = realloc(env->scope_stack, ++env->scope_stack_size * sizeof *env->scope_stack);
 	assert(env->scope_stack != NULL);
 

tests.sh

@@ -8,7 +8,7 @@ for test in $(ls -p tests | grep -v /); do
 		continue
 	fi
 
-	echo -n "Running test $test... "
+	printf "Running test $test... "
 	bin/flamingo tests/$test > /dev/null
 
 	if [ $? = 0 ]; then