bpo-39639: Remove the AST "Suite" node and associated code (GH-18513)

The AST "Suite" node is no longer used and it can be removed from the ASDL definition and related structures (compiler, visitors, ...).

Co-Authored-By: Victor Stinner <vstinner@python.org>
Co-authored-by: Brett Cannon <54418+brettcannon@users.noreply.github.com>
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>

Doc/whatsnew/3.9.rst

@@ -611,6 +611,9 @@ Removed
   defining ``COUNT_ALLOCS`` macro.
   (Contributed by Victor Stinner in :issue:`39489`.)
 
+* The ``ast.Suite`` node class has been removed due to no longer being needed.
+  (Contributed by Batuhan Taskaya in :issue:`39639`.)
+
 
 Porting to Python 3.9
 =====================

Lib/test/test_asdl_parser.py

@@ -118,7 +118,7 @@ def visitConstructor(self, cons):
         v = CustomVisitor()
         v.visit(self.types['mod'])
         self.assertEqual(v.names_with_seq,
-                         ['Module', 'Module', 'Interactive', 'FunctionType', 'Suite'])
+                         ['Module', 'Module', 'Interactive', 'FunctionType'])
 
 
 if __name__ == '__main__':

Misc/NEWS.d/next/Core and Builtins/2020-02-15-15-29-34.bpo-39639.3mqJjm.rst

@@ -0,0 +1 @@
+Remove ``ast.Suite`` node class because it's no longer used. Patch by Batuhan Taskaya.

Parser/Python.asdl

@@ -3,14 +3,11 @@
 
 module Python
 {
-    mod = Module(stmt* body, type_ignore *type_ignores)
+    mod = Module(stmt* body, type_ignore* type_ignores)
         | Interactive(stmt* body)
         | Expression(expr body)
         | FunctionType(expr* argtypes, expr returns)
 
-        -- not really an actual node but useful in Jython's typesystem.
-        | Suite(stmt* body)
-
     stmt = FunctionDef(identifier name, arguments args,
                        stmt* body, expr* decorator_list, expr? returns,
                        string? type_comment)
@@ -51,7 +48,6 @@ module Python
           | Expr(expr value)
           | Pass | Break | Continue
 
-          -- XXX Jython will be different
           -- col_offset is the byte offset in the utf8 string the parser uses
           attributes (int lineno, int col_offset, int? end_lineno, int? end_col_offset)
 

Python/ast.c

@@ -545,9 +545,6 @@ PyAST_Validate(mod_ty mod)
     case Expression_kind:
         res = validate_expr(mod->v.Expression.body, Load);
         break;
-    case Suite_kind:
-        PyErr_SetString(PyExc_ValueError, "Suite is not valid in the CPython compiler");
-        break;
     default:
         PyErr_SetString(PyExc_SystemError, "impossible module node");
         res = 0;

Python/ast_opt.c

@@ -462,9 +462,6 @@ astfold_mod(mod_ty node_, PyArena *ctx_, int optimize_)
     case Expression_kind:
         CALL(astfold_expr, expr_ty, node_->v.Expression.body);
         break;
-    case Suite_kind:
-        CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Suite.body);
-        break;
     default:
         break;
     }

Python/compile.c

@@ -1862,10 +1862,6 @@ compiler_mod(struct compiler *c, mod_ty mod)
         VISIT_IN_SCOPE(c, expr, mod->v.Expression.body);
         addNone = 0;
         break;
-    case Suite_kind:
-        PyErr_SetString(PyExc_SystemError,
-                        "suite should not be possible");
-        return 0;
     default:
         PyErr_Format(PyExc_SystemError,
                      "module kind %d should not be possible",

Python/symtable.c

@@ -318,10 +318,6 @@ PySymtable_BuildObject(mod_ty mod, PyObject *filename, PyFutureFeatures *future)
                         (stmt_ty)asdl_seq_GET(seq, i)))
                 goto error;
         break;
-    case Suite_kind:
-        PyErr_SetString(PyExc_RuntimeError,
-                        "this compiler does not handle Suites");
-        goto error;
     case FunctionType_kind:
         PyErr_SetString(PyExc_RuntimeError,
                         "this compiler does not handle FunctionTypes");