[mypyc] feat: try constant fold in convert_format_expr_to_str

Author: BobTheBuidler

mypyc/irbuild/format_str_tokenizer.py

@@ -143,16 +143,19 @@ def convert_format_expr_to_str(
     for x, format_op in zip(exprs, format_ops):
         node_type = builder.node_type(x)
         if format_op == FormatOp.STR:
-            if is_str_rprimitive(node_type) or isinstance(
-                x, StrExpr
-            ):  # NOTE: why does mypyc think our fake StrExprs are not str rprimitives?
+            if is_str_rprimitive(node_type) or isinstance(x, StrExpr):
+                # NOTE: why does mypyc think our fake StrExprs are not str rprimitives?
                 var_str = builder.accept(x)
+            elif (folded := constant_fold_expr(builder, x)) is not None:
+                var_str = builder.accept(StrExpr(str(folded)))
             elif is_int_rprimitive(node_type) or is_short_int_rprimitive(node_type):
                 var_str = builder.primitive_op(int_to_str_op, [builder.accept(x)], line)
             else:
                 var_str = builder.primitive_op(str_op, [builder.accept(x)], line)
         elif format_op == FormatOp.INT:
-            if is_int_rprimitive(node_type) or is_short_int_rprimitive(node_type):
+            if isinstance(folded := constant_fold_expr(builder, x), int):
+                var_str = builder.accept(StrExpr(str(folded)))
+            elif is_int_rprimitive(node_type) or is_short_int_rprimitive(node_type):
                 var_str = builder.primitive_op(int_to_str_op, [builder.accept(x)], line)
             else:
                 return None