bpo-39939: Add str.removeprefix and str.removesuffix (GH-18939)
Added str.removeprefix and str.removesuffix methods and corresponding
bytes, bytearray, and collections.UserString methods to remove affixes
from a string if present. See PEP 616 for a full description.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 51775df..aba7407 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -12789,6 +12789,61 @@
return replace(self, old, new, count);
}
+/*[clinic input]
+str.removeprefix as unicode_removeprefix
+
+ prefix: unicode
+ /
+
+Return a str with the given prefix string removed if present.
+
+If the string starts with the prefix string, return string[len(prefix):].
+Otherwise, return a copy of the original string.
+[clinic start generated code]*/
+
+static PyObject *
+unicode_removeprefix_impl(PyObject *self, PyObject *prefix)
+/*[clinic end generated code: output=f1e5945e9763bcb9 input=27ec40b99a37eb88]*/
+{
+ int match = tailmatch(self, prefix, 0, PY_SSIZE_T_MAX, -1);
+ if (match == -1) {
+ return NULL;
+ }
+ if (match) {
+ return PyUnicode_Substring(self, PyUnicode_GET_LENGTH(prefix),
+ PyUnicode_GET_LENGTH(self));
+ }
+ return unicode_result_unchanged(self);
+}
+
+/*[clinic input]
+str.removesuffix as unicode_removesuffix
+
+ suffix: unicode
+ /
+
+Return a str with the given suffix string removed if present.
+
+If the string ends with the suffix string and that suffix is not empty,
+return string[:-len(suffix)]. Otherwise, return a copy of the original
+string.
+[clinic start generated code]*/
+
+static PyObject *
+unicode_removesuffix_impl(PyObject *self, PyObject *suffix)
+/*[clinic end generated code: output=d36629e227636822 input=12cc32561e769be4]*/
+{
+ int match = tailmatch(self, suffix, 0, PY_SSIZE_T_MAX, +1);
+ if (match == -1) {
+ return NULL;
+ }
+ if (match) {
+ return PyUnicode_Substring(self, 0, PyUnicode_GET_LENGTH(self)
+ - PyUnicode_GET_LENGTH(suffix));
+ }
+ return unicode_result_unchanged(self);
+}
+
static PyObject *
unicode_repr(PyObject *unicode)
{
@@ -14105,6 +14160,8 @@
UNICODE_UPPER_METHODDEF
{"startswith", (PyCFunction) unicode_startswith, METH_VARARGS, startswith__doc__},
{"endswith", (PyCFunction) unicode_endswith, METH_VARARGS, endswith__doc__},
+ UNICODE_REMOVEPREFIX_METHODDEF
+ UNICODE_REMOVESUFFIX_METHODDEF
UNICODE_ISASCII_METHODDEF
UNICODE_ISLOWER_METHODDEF
UNICODE_ISUPPER_METHODDEF