bpo-30134: fix BytesWarning doc, docstring and message (GH-12739)

Doc/library/exceptions.rst

@@ -526,7 +526,7 @@ module for more information.
 
 .. exception:: BytesWarning
 
-   Base class for warnings related to :class:`str` and :class:`bytearray`.
+   Base class for warnings related to bytes and bytearray.
 
    .. versionadded:: 2.6
 

Doc/library/warnings.rst

@@ -92,7 +92,7 @@ following warnings category classes are currently defined:
 |                                  | Unicode.                                      |
 +----------------------------------+-----------------------------------------------+
 | :exc:`BytesWarning`              | Base category for warnings related to         |
-|                                  | str and bytearray.                            |
+|                                  | bytes and bytearray.                          |
 +----------------------------------+-----------------------------------------------+
 
 While these are technically built-in exceptions, they are documented here,

Include/code.h

@@ -104,7 +104,7 @@ PyAPI_FUNC(int) _PyCode_CheckLineNumber(PyCodeObject* co,
  *
  * Return (type(obj), obj, ...): a tuple with variable size (at least 2 items)
  * depending on the type and the value. The type is the first item to not
- * compare bytes and str which can raise a BytesWarning exception. */
+ * compare bytes and unicode which can raise a BytesWarning exception. */
 PyAPI_FUNC(PyObject*) _PyCode_ConstantKey(PyObject *obj);
 
 PyAPI_FUNC(PyObject*) PyCode_Optimize(PyObject *code, PyObject* consts,

Objects/bytearrayobject.c

@@ -1027,14 +1027,6 @@ bytearray_repr(PyByteArrayObject *self)
 static PyObject *
 bytearray_str(PyObject *op)
 {
-#if 0
-    if (Py_BytesWarningFlag) {
-        if (PyErr_WarnEx(PyExc_BytesWarning,
-                 "str() on a bytearray instance", 1))
-            return NULL;
-    }
-    return bytearray_repr((PyByteArrayObject*)op);
-#endif
     return PyBytes_FromStringAndSize(((PyByteArrayObject*)op)->ob_bytes, Py_SIZE(op));
 }
 
@@ -1059,7 +1051,7 @@ bytearray_richcompare(PyObject *self, PyObject *other, int op)
     if (rc) {
         if (Py_BytesWarningFlag && op == Py_EQ) {
             if (PyErr_WarnEx(PyExc_BytesWarning,
-                            "Comparison between bytearray and string", 1))
+                            "Comparison between bytearray and unicode", 1))
                 return NULL;
         }
 

Objects/exceptions.c

@@ -2014,8 +2014,8 @@ SimpleExtendsException(PyExc_Warning, UnicodeWarning,
  *    BytesWarning extends Warning
  */
 SimpleExtendsException(PyExc_Warning, BytesWarning,
-    "Base class for warnings about bytes and buffer related problems, mostly\n"
-    "related to conversion from str or comparing to str.");
+    "Base class for warnings about bytes and bytearray related problems, \n"
+    "mostly related to comparing to str.");
 
 /* Pre-computed MemoryError instance.  Best to create this as early as
  * possible and not wait until a MemoryError is actually raised!

Python/pythonrun.c

@@ -70,7 +70,7 @@ int Py_VerboseFlag; /* Needed by import.c */
 int Py_InteractiveFlag; /* Needed by Py_FdIsInteractive() below */
 int Py_InspectFlag; /* Needed to determine whether to exit at SystemExit */
 int Py_NoSiteFlag; /* Suppress 'import site' */
-int Py_BytesWarningFlag; /* Warn on str(bytes) and str(buffer) */
+int Py_BytesWarningFlag; /* Warn on comparison between bytearray and unicode */
 int Py_DontWriteBytecodeFlag; /* Suppress writing bytecode files (*.py[co]) */
 int Py_UseClassExceptionsFlag = 1; /* Needed by bltinmodule.c: deprecated */
 int Py_FrozenFlag; /* Needed by getpath.c */