Fine-tune int types

ast/asdl_rs.py

@@ -24,6 +24,10 @@ builtin_type_mapping = {
 }
 assert builtin_type_mapping.keys() == asdl.builtin_types
 
+builtin_int_mapping = {
+    "simple": "bool",
+    "is_async": "bool",
+}
 
 def rust_type_name(name):
     """Return a string for the C name of the type.
@@ -31,7 +35,8 @@ def rust_type_name(name):
     This function special cases the default types provided by asdl.
     """
     if name in asdl.builtin_types:
-        return builtin_type_mapping[name]
+        builtin =  builtin_type_mapping[name]
+        return builtin
     elif name.islower():
         return "".join(part.capitalize() for part in name.split("_"))
     else:
@@ -355,6 +360,8 @@ class StructVisitor(EmitVisitor):
             typ = f"Option<{typ}>"
         if field.seq:
             typ = f"Vec<{typ}>"
+        if typ == "Int":
+            typ = builtin_int_mapping.get(field.name, typ)
         name = rust_field(field.name)
         self.emit(f"{vis}{name}: {typ},", depth)
 

ast/src/gen/generic.rs

@@ -154,7 +154,7 @@ pub struct StmtAnnAssign<U = ()> {
     pub target: Box<Expr<U>>,
     pub annotation: Box<Expr<U>>,
     pub value: Option<Box<Expr<U>>>,
-    pub simple: Int,
+    pub simple: bool,
 }
 
 impl<U> From<StmtAnnAssign<U>> for StmtKind<U> {
@@ -815,7 +815,7 @@ pub struct Comprehension<U = ()> {
     pub target: Expr<U>,
     pub iter: Expr<U>,
     pub ifs: Vec<Expr<U>>,
-    pub is_async: Int,
+    pub is_async: bool,
 }
 
 #[derive(Clone, Debug, PartialEq)]

ast/src/unparse.rs

@@ -429,7 +429,7 @@ impl<'a> Unparser<'a> {
 
     fn unparse_comp<U>(&mut self, generators: &[Comprehension<U>]) -> fmt::Result {
         for comp in generators {
-            self.p(if comp.is_async.to_bool() {
+            self.p(if comp.is_async {
                 " async for "
             } else {
                 " for "