Don't store special method names in co_consts and fix error messages

python · markshannon · Jun 18, 2024 · Jun 17, 2024 · Jun 17, 2024 · Jun 17, 2024
commit 69db48b6f684968dcebc2af1a76625973a9625ab
diff --git a/Include/ceval.h b/Include/ceval.h
@@ -133,6 +133,13 @@ PyAPI_FUNC(void) PyEval_ReleaseThread(PyThreadState *tstate);
 #define FVS_MASK      0x4
 #define FVS_HAVE_SPEC 0x4
 
+/* Special methods used by LOAD_SPECIAL */
+#define SPECIAL___ENTER__   0
+#define SPECIAL___EXIT__    1
+#define SPECIAL___AENTER__  2
+#define SPECIAL___AEXIT__   3
+#define SPECIAL_MAX   3
+
 #ifndef Py_LIMITED_API
 #  define Py_CPYTHON_CEVAL_H
 #  include "cpython/ceval.h"

diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h
@@ -245,6 +245,13 @@ typedef PyObject *(*conversion_func)(PyObject *);
 PyAPI_DATA(const binaryfunc) _PyEval_BinaryOps[];
 PyAPI_DATA(const conversion_func) _PyEval_ConversionFuncs[];
 
+typedef struct _special_method {
+    PyObject *name;
+    const char *error;
+} _Py_SpecialMethod;
+
+PyAPI_DATA(const _Py_SpecialMethod) _Py_SpecialMethods[];
+
 PyAPI_FUNC(int) _PyEval_CheckExceptStarTypeValid(PyThreadState *tstate, PyObject* right);
 PyAPI_FUNC(int) _PyEval_CheckExceptTypeValid(PyThreadState *tstate, PyObject* right);
 PyAPI_FUNC(int) _PyEval_ExceptionGroupMatch(PyObject* exc_value, PyObject *match_type, PyObject **match, PyObject **rest);

diff --git a/Include/internal/pycore_opcode_metadata.h b/Include/internal/pycore_opcode_metadata.h
diff --git a/Include/internal/pycore_uop_metadata.h b/Include/internal/pycore_uop_metadata.h
@@ -2818,15 +2818,14 @@ dummy_func(
             _PUSH_FRAME;
 
         inst(LOAD_SPECIAL, (owner -- attr, self_or_null)) {
-            PyObject *name = GETITEM(FRAME_CO_NAMES, oparg);
+            assert(oparg <= SPECIAL_MAX);
+            PyObject *name = _Py_SpecialMethods[oparg].name;
             attr = _PyObject_LookupSpecialMethod(owner, name, &self_or_null);
             if (attr == NULL) {
                 if (!_PyErr_Occurred(tstate)) {
                     _PyErr_Format(tstate, PyExc_TypeError,
-                                  "'%.200s' object does not support the "
-                                  "context manager protocol "
-                                  "(missed %U method)",
-                                  Py_TYPE(owner)->tp_name, name);
+                                  _Py_SpecialMethods[oparg].error,
+                                  Py_TYPE(owner)->tp_name);
                 }
             }
             ERROR_IF(attr == NULL, error);

@@ -343,6 +343,29 @@ const conversion_func _PyEval_ConversionFuncs[4] = {
     [FVC_ASCII] = PyObject_ASCII
 };
 
+const _Py_SpecialMethod _Py_SpecialMethods[] = {
+    [SPECIAL___ENTER__] = {
+        .name = &_Py_ID(__enter__),
+        .error = "'%.200s' object does not support the "
+                 "context manager protocol (missed __enter__ method)",
+    },
+    [SPECIAL___EXIT__] = {
+        .name = &_Py_ID(__exit__),
+        .error = "'%.200s' object does not support the "
+                 "context manager protocol (missed __exit__ method)",
+    },
+    [SPECIAL___AENTER__] = {
+        .name = &_Py_ID(__aenter__),
+        .error = "'%.200s' object does not support the asynchronous "
+                 "context manager protocol (missed __aenter__ method)",
+    },
+    [SPECIAL___AEXIT__] = {
+        .name = &_Py_ID(__aexit__),
+        .error = "'%.200s' object does not support the asynchronous "
+                 "context manager protocol (missed __aexit__ method)",
+    }
+};
+
 
 // PEP 634: Structural Pattern Matching
 

@@ -5955,10 +5955,10 @@ compiler_async_with(struct compiler *c, stmt_ty s, int pos)
     VISIT(c, expr, item->context_expr);
     loc = LOC(item->context_expr);
     ADDOP_I(c, loc, COPY, 1);
-    ADDOP_NAME(c, loc, LOAD_SPECIAL, &_Py_ID(__aexit__), names);
+    ADDOP_I(c, loc, LOAD_SPECIAL, SPECIAL___AEXIT__);
     ADDOP_I(c, loc, SWAP, 2);
     ADDOP_I(c, loc, SWAP, 3);
-    ADDOP_NAME(c, loc, LOAD_SPECIAL, &_Py_ID(__aenter__), names);
+    ADDOP_I(c, loc, LOAD_SPECIAL, SPECIAL___AENTER__);
     ADDOP_I(c, loc, CALL, 0);
     ADDOP_I(c, loc, GET_AWAITABLE, 1);
     ADDOP_LOAD_CONST(c, loc, Py_None);
@@ -6058,10 +6058,10 @@ compiler_with(struct compiler *c, stmt_ty s, int pos)
     /* Will push bound __exit__ */
     location loc = LOC(item->context_expr);
     ADDOP_I(c, loc, COPY, 1);
-    ADDOP_NAME(c, loc, LOAD_SPECIAL, &_Py_ID(__exit__), names);
+    ADDOP_I(c, loc, LOAD_SPECIAL, SPECIAL___EXIT__);
     ADDOP_I(c, loc, SWAP, 2);
     ADDOP_I(c, loc, SWAP, 3);
-    ADDOP_NAME(c, loc, LOAD_SPECIAL, &_Py_ID(__enter__), names);
+    ADDOP_I(c, loc, LOAD_SPECIAL, SPECIAL___ENTER__);
     ADDOP_I(c, loc, CALL, 0);
     ADDOP_JUMP(c, loc, SETUP_WITH, final);
 

diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h