fix: allow nesting for return run function

examples/basic_nesting/src/data/demo/functions/foo.mcfunction

@@ -192,3 +192,13 @@ function demo:blob:
     append function demo:blob:
         say aaaaa
     say after
+
+function demo:ret1:
+    execute if score some score matches 0 run return run execute run function demo:ret1/cond:
+        say hi
+        return 0
+
+function demo:ret2:
+    execute if score some score matches 0 run return run function demo:ret2/cond:
+        say hi
+        return 0

mecha/contrib/nesting.py

@@ -146,7 +146,8 @@ def nesting_execute_run(self, node: AstCommand):
         return node
 
     @rule(AstCommand, identifier="execute:run:subcommand")
-    def nesting_execute_function(self, node: AstCommand):
+    @rule(AstCommand, identifier="return:run:subcommand")
+    def nesting_run_function(self, node: AstCommand):
         if isinstance(command := node.arguments[0], AstCommand):
             if command.identifier in self.identifier_map:
                 yield from self.handle_function(command)

tests/snapshots/examples__build_basic_nesting__0.pack.md

@@ -253,6 +253,20 @@ say anonymous definition 7
 say anonymous definition 8
 ```
 
+`@function demo:ret1/cond`
+
+```mcfunction
+say hi
+return 0
+```
+
+`@function demo:ret2/cond`
+
+```mcfunction
+say hi
+return 0
+```
+
 `@function demo:thing1`
 
 ```mcfunction
@@ -290,6 +304,18 @@ say aaaaa
 say after
 ```
 
+`@function demo:ret1`
+
+```mcfunction
+execute if score some score matches 0 run return run function demo:ret1/cond
+```
+
+`@function demo:ret2`
+
+```mcfunction
+execute if score some score matches 0 run return run function demo:ret2/cond
+```
+
 `@function demo:wat/nested_execute_0`
 
 ```mcfunction