Partially implement SF feature request 444708.

Add optional arg to string methods strip(), lstrip(), rstrip().
The optional arg specifies characters to delete.

Also for UserString.

Still to do:

- Misc/NEWS
- LaTeX docs (I did the docstrings though)
- Unicode methods, and Unicode support in the string methods.

diff --git a/Lib/UserString.py b/Lib/UserString.py
index 45cdeb5d411779747f75c190faf5003434c0f3a9..f4f5cab96ced91508bd9c77e6a9de604ba47215b 100755 (executable)
--- a/Lib/UserString.py
+++ b/Lib/UserString.py
@@ -108,7 +108,7 @@ class UserString:
     def join(self, seq): return self.data.join(seq)
     def ljust(self, width): return self.__class__(self.data.ljust(width))
     def lower(self): return self.__class__(self.data.lower())
-    def lstrip(self): return self.__class__(self.data.lstrip())
+    def lstrip(self, sep=None): return self.__class__(self.data.lstrip(sep))
     def replace(self, old, new, maxsplit=-1):
         return self.__class__(self.data.replace(old, new, maxsplit))
     def rfind(self, sub, start=0, end=sys.maxint):
@@ -116,13 +116,13 @@ class UserString:
     def rindex(self, sub, start=0, end=sys.maxint):
         return self.data.rindex(sub, start, end)
     def rjust(self, width): return self.__class__(self.data.rjust(width))
-    def rstrip(self): return self.__class__(self.data.rstrip())
+    def rstrip(self, sep=None): return self.__class__(self.data.rstrip(sep))
     def split(self, sep=None, maxsplit=-1):
         return self.data.split(sep, maxsplit)
     def splitlines(self, keepends=0): return self.data.splitlines(keepends)
     def startswith(self, prefix, start=0, end=sys.maxint):
         return self.data.startswith(prefix, start, end)
-    def strip(self): return self.__class__(self.data.strip())
+    def strip(self, sep=None): return self.__class__(self.data.strip(sep))
     def swapcase(self): return self.__class__(self.data.swapcase())
     def title(self): return self.__class__(self.data.title())
     def translate(self, *args):

diff --git a/Lib/test/string_tests.py b/Lib/test/string_tests.py
index 4b2f0e316d27cc585ce8401b81c0604b347eeb19..5c8dd934c6b74b7553d03d17272de5b77d16757f 100644 (file)
--- a/Lib/test/string_tests.py
+++ b/Lib/test/string_tests.py
@@ -163,6 +163,18 @@ def run_method_tests(test):
     test('rstrip', '   hello   ', '   hello')
     test('strip', 'hello', 'hello')
 
+    # strip/lstrip/rstrip with None arg
+    test('strip', '   hello   ', 'hello', None)
+    test('lstrip', '   hello   ', 'hello   ', None)
+    test('rstrip', '   hello   ', '   hello', None)
+    test('strip', 'hello', 'hello', None)
+
+    # strip/lstrip/rstrip with real arg
+    test('strip', 'xyzzyhelloxyzzy', 'hello', 'xyz')
+    test('lstrip', 'xyzzyhelloxyzzy', 'helloxyzzy', 'xyz')
+    test('rstrip', 'xyzzyhelloxyzzy', 'xyzzyhello', 'xyz')
+    test('strip', 'hello', 'hello', 'xyz')
+
     test('swapcase', 'HeLLo cOmpUteRs', 'hEllO CoMPuTErS')
     test('translate', 'xyzabcdef', 'xyzxyz', transtable, 'def')
 

diff --git a/Objects/stringobject.c b/Objects/stringobject.c
index 359e94213a4bdc9bdcb5990550bbe710b34b4654..709c5f79864d3767305e46c38a634a7386b13938 100644 (file)
--- a/Objects/stringobject.c
+++ b/Objects/stringobject.c
@@ -1002,6 +1002,9 @@ static PyBufferProcs string_as_buffer = {
 #define RIGHTSTRIP 1
 #define BOTHSTRIP 2
 
+/* Arrays indexed by above */
+static const char *stripname[] = {"lstrip", "rstrip", "strip"};
+
 
 static PyObject *
 split_whitespace(const char *s, int len, int maxsplit)
@@ -1376,6 +1379,39 @@ string_rindex(PyStringObject *self, PyObject *args)
 }
 
 
+static PyObject *
+do_xstrip(PyStringObject *self, int striptype, PyObject *sepobj)
+{
+       char *s = PyString_AS_STRING(self);
+       int len = PyString_GET_SIZE(self);
+       char *sep = PyString_AS_STRING(sepobj);
+       int seplen = PyString_GET_SIZE(sepobj);
+       int i, j;
+
+       i = 0;
+       if (striptype != RIGHTSTRIP) {
+               while (i < len && memchr(sep, Py_CHARMASK(s[i]), seplen)) {
+                       i++;
+               }
+       }
+
+       j = len;
+       if (striptype != LEFTSTRIP) {
+               do {
+                       j--;
+               } while (j >= i && memchr(sep, Py_CHARMASK(s[j]), seplen));
+               j++;
+       }
+
+       if (i == 0 && j == len && PyString_CheckExact(self)) {
+               Py_INCREF(self);
+               return (PyObject*)self;
+       }
+       else
+               return PyString_FromStringAndSize(s+i, j-i);
+}
+
+
 static PyObject *
 do_strip(PyStringObject *self, int striptype)
 {
@@ -1406,40 +1442,75 @@ do_strip(PyStringObject *self, int striptype)
 }
 
 
+static PyObject *
+do_argstrip(PyStringObject *self, int striptype, PyObject *args)
+{
+       PyObject *sep = NULL;
+
+       if (!PyArg_ParseTuple(args, "|O:[lr]strip", &sep))
+               return NULL;
+
+       if (sep != NULL && sep != Py_None) {
+               /* XXX What about Unicode? */
+               if (!PyString_Check(sep)) {
+                       PyErr_Format(PyExc_TypeError,
+                                    "%s arg must be None or string",
+                                    stripname[striptype]);
+                       return NULL;
+               }
+               return do_xstrip(self, striptype, sep);
+       }
+
+       return do_strip(self, striptype);
+}
+
+
 static char strip__doc__[] =
-"S.strip() -> string\n\
+"S.strip([sep]) -> string\n\
 \n\
 Return a copy of the string S with leading and trailing\n\
-whitespace removed.";
+whitespace removed.\n\
+If sep is given and not None, remove characters in sep instead.";
 
 static PyObject *
-string_strip(PyStringObject *self)
+string_strip(PyStringObject *self, PyObject *args)
 {
-       return do_strip(self, BOTHSTRIP);
+       if (PyTuple_GET_SIZE(args) == 0)
+               return do_strip(self, BOTHSTRIP); /* Common case */
+       else
+               return do_argstrip(self, BOTHSTRIP, args);
 }
 
 
 static char lstrip__doc__[] =
-"S.lstrip() -> string\n\
+"S.lstrip([sep]) -> string\n\
 \n\
-Return a copy of the string S with leading whitespace removed.";
+Return a copy of the string S with leading whitespace removed.\n\
+If sep is given and not None, remove characters in sep instead.";
 
 static PyObject *
-string_lstrip(PyStringObject *self)
+string_lstrip(PyStringObject *self, PyObject *args)
 {
-       return do_strip(self, LEFTSTRIP);
+       if (PyTuple_GET_SIZE(args) == 0)
+               return do_strip(self, LEFTSTRIP); /* Common case */
+       else
+               return do_argstrip(self, LEFTSTRIP, args);
 }
 
 
 static char rstrip__doc__[] =
-"S.rstrip() -> string\n\
+"S.rstrip([sep]) -> string\n\
 \n\
-Return a copy of the string S with trailing whitespace removed.";
+Return a copy of the string S with trailing whitespace removed.\n\
+If sep is given and not None, remove characters in sep instead.";
 
 static PyObject *
-string_rstrip(PyStringObject *self)
+string_rstrip(PyStringObject *self, PyObject *args)
 {
-       return do_strip(self, RIGHTSTRIP);
+       if (PyTuple_GET_SIZE(args) == 0)
+               return do_strip(self, RIGHTSTRIP); /* Common case */
+       else
+               return do_argstrip(self, RIGHTSTRIP, args);
 }
 
 
@@ -2644,13 +2715,13 @@ string_methods[] = {
        {"endswith",   (PyCFunction)string_endswith,    METH_VARARGS, endswith__doc__},
        {"find",       (PyCFunction)string_find,        METH_VARARGS, find__doc__},
        {"index",      (PyCFunction)string_index,       METH_VARARGS, index__doc__},
-       {"lstrip",     (PyCFunction)string_lstrip,      METH_NOARGS, lstrip__doc__},
+       {"lstrip",     (PyCFunction)string_lstrip,      METH_VARARGS, lstrip__doc__},
        {"replace",     (PyCFunction)string_replace,    METH_VARARGS, replace__doc__},
        {"rfind",       (PyCFunction)string_rfind,      METH_VARARGS, rfind__doc__},
        {"rindex",      (PyCFunction)string_rindex,     METH_VARARGS, rindex__doc__},
-       {"rstrip",      (PyCFunction)string_rstrip,     METH_NOARGS, rstrip__doc__},
+       {"rstrip",      (PyCFunction)string_rstrip,     METH_VARARGS, rstrip__doc__},
        {"startswith",  (PyCFunction)string_startswith, METH_VARARGS, startswith__doc__},
-       {"strip",       (PyCFunction)string_strip,      METH_NOARGS, strip__doc__},
+       {"strip",       (PyCFunction)string_strip,      METH_VARARGS, strip__doc__},
        {"swapcase",    (PyCFunction)string_swapcase,   METH_NOARGS, swapcase__doc__},
        {"translate",   (PyCFunction)string_translate,  METH_VARARGS, translate__doc__},
        {"title",       (PyCFunction)string_title,      METH_NOARGS, title__doc__},