Issue 28128: Print out better error/warning messages for invalid string escapes. Backport to 3.6.

2 files changed, 16 insertions, 0 deletions

diff --git a/Include/bytesobject.h b/Include/bytesobject.h
index 11d8218..98e29b6 100644
--- a/Include/bytesobject.h
+++ b/Include/bytesobject.h
@@ -74,6 +74,11 @@ PyAPI_FUNC(PyObject*) _PyBytes_FromHex(
 PyAPI_FUNC(PyObject *) PyBytes_DecodeEscape(const char *, Py_ssize_t,
 						   const char *, Py_ssize_t,
 						   const char *);
+/* Helper for PyBytes_DecodeEscape that detects invalid escape chars. */
+PyAPI_FUNC(PyObject *) _PyBytes_DecodeEscape(const char *, Py_ssize_t,
+                                             const char *, Py_ssize_t,
+                                             const char *,
+                                             const char **);
 
 /* Macro, trading safety for speed */
 #ifndef Py_LIMITED_API
diff --git a/Include/unicodeobject.h b/Include/unicodeobject.h
index 5711de0..b5ef3e4 100644
--- a/Include/unicodeobject.h
+++ b/Include/unicodeobject.h
@@ -1486,6 +1486,17 @@ PyAPI_FUNC(PyObject*) PyUnicode_DecodeUnicodeEscape(
     const char *errors          /* error handling */
     );
 
+/* Helper for PyUnicode_DecodeUnicodeEscape that detects invalid escape
+   chars. */
+PyAPI_FUNC(PyObject*) _PyUnicode_DecodeUnicodeEscape(
+        const char *string,     /* Unicode-Escape encoded string */
+        Py_ssize_t length,      /* size of string */
+        const char *errors,     /* error handling */
+        const char **first_invalid_escape  /* on return, points to first
+                                              invalid escaped char in
+                                              string. */
+);
+
 PyAPI_FUNC(PyObject*) PyUnicode_AsUnicodeEscapeString(
     PyObject *unicode           /* Unicode object */
     );