PublicArchive/cpython
2
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2026-05-06 04:37:33 -04:00
Code Issues Packages Projects Releases Wiki Activity

gh-145239: Accept unary plus literal pattern (#148566)

Browse Source 
Add '+' alternatives to signed_number and signed_real_number grammar
rules, mirroring how unary minus is already handled for pattern matching.
Unary plus is a no-op on numbers so the value is returned directly without
wrapping in a UnaryOp node.
This commit is contained in:
Bartosz Sławecki
2026-04-23 21:07:28 +02:00
committed by GitHub
parent 4629c2215a
commit 448d7b96c1
7 changed files with 187 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Doc/reference/compound_stmts.rst
+1 -1
View File
@@ -858,7 +858,7 @@ A literal pattern corresponds to most
: | "None"
: | "True"
: | "False"
signed_number: ["-"] NUMBER
signed_number: ["+" | "-"] NUMBER
The rule ``strings`` and the token ``NUMBER`` are defined in the
:doc:`standard Python grammar <./grammar>`. Triple-quoted strings are
Doc/whatsnew/3.15.rst
+4
View File
@@ -645,6 +645,10 @@ Other language changes
* Allow the *count* argument of :meth:`bytes.replace` to be a keyword.
(Contributed by Stan Ulbrych in :gh:`147856`.)
* Unary plus is now accepted in :keyword:`match` literal patterns, mirroring
the existing support for unary minus.
(Contributed by Bartosz Sławecki in :gh:`145239`.)
New modules
===========
Grammar/python.gram
+3
View File
@@ -554,10 +554,12 @@ complex_number[expr_ty]:
signed_number[expr_ty]:
| NUMBER
| '+' number=NUMBER { number }
| '-' number=NUMBER { _PyAST_UnaryOp(USub, number, EXTRA) }
signed_real_number[expr_ty]:
| real_number
| '+' real=real_number { real }
| '-' real=real_number { _PyAST_UnaryOp(USub, real, EXTRA) }
real_number[expr_ty]:
@@ -565,6 +567,7 @@ real_number[expr_ty]:
imaginary_number[expr_ty]:
| imag=NUMBER { _PyPegen_ensure_imaginary(p, imag) }
| '+' imag=NUMBER { _PyPegen_ensure_imaginary(p, imag) }
capture_pattern[pattern_ty]:
| target=pattern_capture_target { _PyAST_MatchAs(NULL, target->v.Name.id, EXTRA) }
Lib/test/.ruff.toml
+2
View File
@@ -18,6 +18,8 @@ extend-exclude = [
"test_lazy_import/__init__.py",
"test_lazy_import/data/*.py",
"test_lazy_import/data/**/*.py",
# Unary plus literal pattern is not yet supported by Ruff (GH-145239)
"test_patma.py",
]
[lint]
Lib/test/test_patma.py
+90
View File
@@ -2762,6 +2762,96 @@ class TestPatma(unittest.TestCase):
self.assertEqual(y, 1)
self.assertIs(z, x)
def test_patma_256(self):
x = 0
match x:
case +0:
y = 0
self.assertEqual(x, 0)
self.assertEqual(y, 0)
def test_patma_257(self):
x = 0
match x:
case +0.0:
y = 0
self.assertEqual(x, 0)
self.assertEqual(y, 0)
def test_patma_258(self):
x = 0
match x:
case +0j:
y = 0
self.assertEqual(x, 0)
self.assertEqual(y, 0)
def test_patma_259(self):
x = 0
match x:
case +0.0j:
y = 0
self.assertEqual(x, 0)
self.assertEqual(y, 0)
def test_patma_260(self):
x = 1
match x:
case +1:
y = 0
self.assertEqual(x, 1)
self.assertEqual(y, 0)
def test_patma_261(self):
x = 1.5
match x:
case +1.5:
y = 0
self.assertEqual(x, 1.5)
self.assertEqual(y, 0)
def test_patma_262(self):
x = 1j
match x:
case +1j:
y = 0
self.assertEqual(x, 1j)
self.assertEqual(y, 0)
def test_patma_263(self):
x = 1.5j
match x:
case +1.5j:
y = 0
self.assertEqual(x, 1.5j)
self.assertEqual(y, 0)
def test_patma_264(self):
x = 0.25 + 1.75j
match x:
case +0.25 + 1.75j:
y = 0
self.assertEqual(x, 0.25 + 1.75j)
self.assertEqual(y, 0)
def test_patma_265(self):
x = 0.25 - 1.75j
match x:
case 0.25 - +1.75j:
y = 0
self.assertEqual(x, 0.25 - 1.75j)
self.assertEqual(y, 0)
def test_patma_266(self):
x = 0
match x:
case +1e1000:
y = 0
case 0:
y = 1
self.assertEqual(x, 0)
self.assertEqual(y, 1)
def test_patma_runtime_checkable_protocol(self):
# Runtime-checkable protocol
from typing import Protocol, runtime_checkable
Misc/NEWS.d/next/Core_and_Builtins/2026-04-13-23-21-45.gh-issue-145239.pL8qRt.rst
+3
View File
@@ -0,0 +1,3 @@
Unary plus is now accepted in :keyword:`match` literal patterns, mirroring
the existing support for unary minus.
Patch by Bartosz Sławecki.
Parser/parser.c
Generated
+84 -3
View File
@@ -9066,7 +9066,7 @@ complex_number_rule(Parser *p)
return _res;
}
// signed_number: NUMBER | '-' NUMBER
// signed_number: NUMBER | '+' NUMBER | '-' NUMBER
static expr_ty
signed_number_rule(Parser *p)
{
@@ -9107,6 +9107,33 @@ signed_number_rule(Parser *p)
D(fprintf(stderr, "%*c%s signed_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "NUMBER"));
}
{ // '+' NUMBER
if (p->error_indicator) {
p->level--;
return NULL;
}
D(fprintf(stderr, "%*c> signed_number[%d-%d]: %s\n", p->level, ' ', _mark, p->mark, "'+' NUMBER"));
Token * _literal;
expr_ty number;
if (
(_literal = _PyPegen_expect_token(p, 14)) // token='+'
&&
(number = _PyPegen_number_token(p)) // NUMBER
)
{
D(fprintf(stderr, "%*c+ signed_number[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "'+' NUMBER"));
_res = number;
if ((_res == NULL || p->error_indicator) && PyErr_Occurred()) {
p->error_indicator = 1;
p->level--;
return NULL;
}
goto done;
}
p->mark = _mark;
D(fprintf(stderr, "%*c%s signed_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "'+' NUMBER"));
}
{ // '-' NUMBER
if (p->error_indicator) {
p->level--;
@@ -9149,7 +9176,7 @@ signed_number_rule(Parser *p)
return _res;
}
// signed_real_number: real_number | '-' real_number
// signed_real_number: real_number | '+' real_number | '-' real_number
static expr_ty
signed_real_number_rule(Parser *p)
{
@@ -9190,6 +9217,33 @@ signed_real_number_rule(Parser *p)
D(fprintf(stderr, "%*c%s signed_real_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "real_number"));
}
{ // '+' real_number
if (p->error_indicator) {
p->level--;
return NULL;
}
D(fprintf(stderr, "%*c> signed_real_number[%d-%d]: %s\n", p->level, ' ', _mark, p->mark, "'+' real_number"));
Token * _literal;
expr_ty real;
if (
(_literal = _PyPegen_expect_token(p, 14)) // token='+'
&&
(real = real_number_rule(p)) // real_number
)
{
D(fprintf(stderr, "%*c+ signed_real_number[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "'+' real_number"));
_res = real;
if ((_res == NULL || p->error_indicator) && PyErr_Occurred()) {
p->error_indicator = 1;
p->level--;
return NULL;
}
goto done;
}
p->mark = _mark;
D(fprintf(stderr, "%*c%s signed_real_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "'+' real_number"));
}
{ // '-' real_number
if (p->error_indicator) {
p->level--;
@@ -9275,7 +9329,7 @@ real_number_rule(Parser *p)
return _res;
}
// imaginary_number: NUMBER
// imaginary_number: NUMBER | '+' NUMBER
static expr_ty
imaginary_number_rule(Parser *p)
{
@@ -9312,6 +9366,33 @@ imaginary_number_rule(Parser *p)
D(fprintf(stderr, "%*c%s imaginary_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "NUMBER"));
}
{ // '+' NUMBER
if (p->error_indicator) {
p->level--;
return NULL;
}
D(fprintf(stderr, "%*c> imaginary_number[%d-%d]: %s\n", p->level, ' ', _mark, p->mark, "'+' NUMBER"));
Token * _literal;
expr_ty imag;
if (
(_literal = _PyPegen_expect_token(p, 14)) // token='+'
&&
(imag = _PyPegen_number_token(p)) // NUMBER
)
{
D(fprintf(stderr, "%*c+ imaginary_number[%d-%d]: %s succeeded!\n", p->level, ' ', _mark, p->mark, "'+' NUMBER"));
_res = _PyPegen_ensure_imaginary ( p , imag );
if ((_res == NULL || p->error_indicator) && PyErr_Occurred()) {
p->error_indicator = 1;
p->level--;
return NULL;
}
goto done;
}
p->mark = _mark;
D(fprintf(stderr, "%*c%s imaginary_number[%d-%d]: %s failed!\n", p->level, ' ',
p->error_indicator ? "ERROR!" : "-", _mark, p->mark, "'+' NUMBER"));
}
_res = NULL;
done:
p->level--;