bpo-39969: Remove ast.Param node class as is no longer used (GH-19020)

Author: isidentical

Doc/whatsnew/3.9.rst

@@ -664,8 +664,9 @@ 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`.)
+* The ``ast.Suite`` and ``ast.Param`` node classes has been removed due to no
+ longer being needed.
+ (Contributed by Batuhan Taskaya in :issue:`39639` and :issue:`39969`.)
 
 
 Porting to Python 3.9

Include/Python-ast.h

@@ -0,0 +1,2 @@
+Remove ``ast.Param`` node class because it's no longer used. Patch by
+Batuhan Taskaya.

Misc/NEWS.d/next/Library/2020-03-15-17-56-48.bpo-39969.6snm0c.rst

@@ -90,7 +90,7 @@ module Python
  -- 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)
 
- expr_context = Load | Store | Del | AugLoad | AugStore | Param
+ expr_context = Load | Store | Del | AugLoad | AugStore
 
  boolop = And | Or
 

Parser/Python.asdl

@@ -75,8 +75,6 @@ expr_context_name(expr_context_ty ctx)
  return "AugLoad";
  case AugStore:
  return "AugStore";
- case Param:
- return "Param";
  default:
  Py_UNREACHABLE();
  }

Python/Python-ast.c

@@ -3579,10 +3579,10 @@ compiler_nameop(struct compiler *c, identifier name, expr_context_ty ctx)
  case AugStore:
  break;
  case Del: op = DELETE_DEREF; break;
- case Param:
  default:
- PyErr_SetString(PyExc_SystemError,
- "param invalid for deref variable");
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ ctx);
  return 0;
  }
  break;
@@ -3596,10 +3596,10 @@ compiler_nameop(struct compiler *c, identifier name, expr_context_ty ctx)
  case AugLoad:
  case AugStore:
  break;
- case Param:
  default:
- PyErr_SetString(PyExc_SystemError,
- "param invalid for local variable");
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ ctx);
  return 0;
  }
  ADDOP_N(c, op, mangled, varnames);
@@ -3614,10 +3614,10 @@ compiler_nameop(struct compiler *c, identifier name, expr_context_ty ctx)
  case AugLoad:
  case AugStore:
  break;
- case Param:
  default:
- PyErr_SetString(PyExc_SystemError,
- "param invalid for global variable");
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ ctx);
  return 0;
  }
  break;
@@ -3631,10 +3631,10 @@ compiler_nameop(struct compiler *c, identifier name, expr_context_ty ctx)
  case AugLoad:
  case AugStore:
  break;
- case Param:
  default:
- PyErr_SetString(PyExc_SystemError,
- "param invalid for name variable");
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ ctx);
  return 0;
  }
  break;
@@ -5058,10 +5058,10 @@ compiler_visit_expr1(struct compiler *c, expr_ty e)
  case Del:
  ADDOP_NAME(c, DELETE_ATTR, e->v.Attribute.attr, names);
  break;
- case Param:
  default:
- PyErr_SetString(PyExc_SystemError,
- "param invalid in attribute expression");
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ e->v.Attribute.ctx);
  return 0;
  }
  break;
@@ -5359,9 +5359,10 @@ compiler_subscript(struct compiler *c, expr_ty e)
  case AugStore:/* fall through to Store */
  case Store: op = STORE_SUBSCR; break;
  case Del: op = DELETE_SUBSCR; break;
- case Param:
- PyErr_SetString(PyExc_SystemError,
- "param invalid in subscript expression");
+ default:
+ PyErr_Format(PyExc_SystemError,
+ "expr_context kind %d should not be possible",
+ ctx);
  return 0;
  }
  if (ctx == AugStore) {