diff --git a/Lib/test/test_string/_support.py b/Lib/test/test_string/_support.py
index abdddaf187b4fe..e1d7f6f6500aeb 100644
--- a/Lib/test/test_string/_support.py
+++ b/Lib/test/test_string/_support.py
@@ -2,33 +2,45 @@
class TStringBaseCase:
+ def assertInterpolationEqual(self, i, exp):
+ """Test Interpolation equality.
+
+ The *i* argument must be an Interpolation instance.
+
+ The *exp* argument must be a tuple of the form
+ (value, expression, conversion, format_spec) where the final three
+ items may be omitted and are assumed to be '', None and '' respectively.
+ """
+ if len(exp) == 4:
+ actual = (i.value, i.expression, i.conversion, i.format_spec)
+ self.assertEqual(actual, exp)
+ elif len(exp) == 3:
+ self.assertEqual((i.value, i.expression, i.conversion), exp)
+ self.assertEqual(i.format_spec, "")
+ elif len(exp) == 2:
+ self.assertEqual((i.value, i.expression), exp)
+ self.assertEqual(i.conversion, None)
+ self.assertEqual(i.format_spec, "")
+ elif len(exp) == 1:
+ self.assertEqual((i.value,), exp)
+ self.assertEqual(i.expression, "")
+ self.assertEqual(i.conversion, None)
+ self.assertEqual(i.format_spec, "")
+
def assertTStringEqual(self, t, strings, interpolations):
"""Test template string literal equality.
The *strings* argument must be a tuple of strings equal to *t.strings*.
The *interpolations* argument must be a sequence of tuples which are
- compared against *t.interpolations*. Each tuple consists of
- (value, expression, conversion, format_spec), though the final two
- items may be omitted, and are assumed to be None and '' respectively.
+ compared against *t.interpolations*. Each tuple must match the form
+ described in the `assertInterpolationEqual` method.
"""
self.assertEqual(t.strings, strings)
self.assertEqual(len(t.interpolations), len(interpolations))
for i, exp in zip(t.interpolations, interpolations, strict=True):
- if len(exp) == 4:
- actual = (i.value, i.expression, i.conversion, i.format_spec)
- self.assertEqual(actual, exp)
- continue
-
- if len(exp) == 3:
- self.assertEqual((i.value, i.expression, i.conversion), exp)
- self.assertEqual(i.format_spec, '')
- continue
-
- self.assertEqual((i.value, i.expression), exp)
- self.assertEqual(i.format_spec, '')
- self.assertIsNone(i.conversion)
+ self.assertInterpolationEqual(i, exp)
def convert(value, conversion):
diff --git a/Lib/test/test_string/test_templatelib.py b/Lib/test/test_string/test_templatelib.py
index 85fcff486d6616..adaf590e64dad6 100644
--- a/Lib/test/test_string/test_templatelib.py
+++ b/Lib/test/test_string/test_templatelib.py
@@ -45,6 +45,19 @@ def test_basic_creation(self):
self.assertEqual(len(t.interpolations), 0)
self.assertEqual(fstring(t), 'Hello,\nworld')
+ def test_interpolation_creation(self):
+ i = Interpolation('Maria', 'name', 'a', 'fmt')
+ self.assertInterpolationEqual(i, ('Maria', 'name', 'a', 'fmt'))
+
+ i = Interpolation('Maria', 'name', 'a')
+ self.assertInterpolationEqual(i, ('Maria', 'name', 'a'))
+
+ i = Interpolation('Maria', 'name')
+ self.assertInterpolationEqual(i, ('Maria', 'name'))
+
+ i = Interpolation('Maria')
+ self.assertInterpolationEqual(i, ('Maria',))
+
def test_creation_interleaving(self):
# Should add strings on either side
t = Template(Interpolation('Maria', 'name', None, ''))
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-07-08-23-53-51.gh-issue-132661.B84iYt.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-08-23-53-51.gh-issue-132661.B84iYt.rst
new file mode 100644
index 00000000000000..9930413b53c150
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-08-23-53-51.gh-issue-132661.B84iYt.rst
@@ -0,0 +1 @@
+``Interpolation.expression`` now has a default, the empty string.
diff --git a/Objects/clinic/interpolationobject.c.h b/Objects/clinic/interpolationobject.c.h
index 7a94dabafc92f2..2030e17e49e47a 100644
--- a/Objects/clinic/interpolationobject.c.h
+++ b/Objects/clinic/interpolationobject.c.h
@@ -47,26 +47,31 @@ interpolation_new(PyTypeObject *type, PyObject *args, PyObject *kwargs)
PyObject *argsbuf[4];
PyObject * const *fastargs;
Py_ssize_t nargs = PyTuple_GET_SIZE(args);
- Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 2;
+ Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 1;
PyObject *value;
- PyObject *expression;
+ PyObject *expression = &_Py_STR(empty);
PyObject *conversion = Py_None;
PyObject *format_spec = &_Py_STR(empty);
fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser,
- /*minpos*/ 2, /*maxpos*/ 4, /*minkw*/ 0, /*varpos*/ 0, argsbuf);
+ /*minpos*/ 1, /*maxpos*/ 4, /*minkw*/ 0, /*varpos*/ 0, argsbuf);
if (!fastargs) {
goto exit;
}
value = fastargs[0];
- if (!PyUnicode_Check(fastargs[1])) {
- _PyArg_BadArgument("Interpolation", "argument 'expression'", "str", fastargs[1]);
- goto exit;
- }
- expression = fastargs[1];
if (!noptargs) {
goto skip_optional_pos;
}
+ if (fastargs[1]) {
+ if (!PyUnicode_Check(fastargs[1])) {
+ _PyArg_BadArgument("Interpolation", "argument 'expression'", "str", fastargs[1]);
+ goto exit;
+ }
+ expression = fastargs[1];
+ if (!--noptargs) {
+ goto skip_optional_pos;
+ }
+ }
if (fastargs[2]) {
if (!_conversion_converter(fastargs[2], &conversion)) {
goto exit;
@@ -86,4 +91,4 @@ interpolation_new(PyTypeObject *type, PyObject *args, PyObject *kwargs)
exit:
return return_value;
}
-/*[clinic end generated code: output=599742a5ccd6f060 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2391391e2d7708c0 input=a9049054013a1b77]*/
diff --git a/Objects/interpolationobject.c b/Objects/interpolationobject.c
index a5d407a7b0e296..b58adb693f0cae 100644
--- a/Objects/interpolationobject.c
+++ b/Objects/interpolationobject.c
@@ -54,7 +54,7 @@ typedef struct {
Interpolation.__new__ as interpolation_new
value: object
- expression: object(subclass_of='&PyUnicode_Type')
+ expression: object(subclass_of='&PyUnicode_Type', c_default='&_Py_STR(empty)') = ""
conversion: object(converter='_conversion_converter') = None
format_spec: object(subclass_of='&PyUnicode_Type', c_default='&_Py_STR(empty)') = ""
[clinic start generated code]*/
@@ -63,7 +63,7 @@ static PyObject *
interpolation_new_impl(PyTypeObject *type, PyObject *value,
PyObject *expression, PyObject *conversion,
PyObject *format_spec)
-/*[clinic end generated code: output=6488e288765bc1a9 input=d91711024068528c]*/
+/*[clinic end generated code: output=6488e288765bc1a9 input=fc5c285c1dd23d36]*/
{
interpolationobject *self = PyObject_GC_New(interpolationobject, type);
if (!self) {
pFad - Phonifier reborn
Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.
Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.
Alternative Proxies:
Alternative Proxy
pFad Proxy
pFad v3 Proxy
pFad v4 Proxy