copy new file "Lib/test/support/testcase.py" for test_float.py

.github/workflows/ai-review.yml

@@ -0,0 +1,23 @@
+name: PR Review
+
+on:
+  pull_request:
+    types: [opened, synchronize]
+
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  review:
+    runs-on: ubuntu-latest
+    steps:
+      - name: AI Code Review
+        uses: gitea-actions/ai-reviewer@v0.6
+        with:
+          access-token: ${{ secrets.ACCESS_TOKEN }}
+          full-context-model: "gpt-4o"
+          full-context-api-key: ${{ secrets.OPENAI_API_KEY }}
+          single-chunk-model: "claude-3-5-sonnet"
+          single-chunk-api-key: ${{ secrets.ANTHROPIC_API_KEY }}
+          exclude-files: "*.md,*.yaml"

Lib/test/support/testcase.py

@@ -0,0 +1,65 @@
+from math import copysign, isnan
+
+
+class ExceptionIsLikeMixin:
+    def assertExceptionIsLike(self, exc, template):
+        """
+        Passes when the provided `exc` matches the structure of `template`.
+        Individual exceptions don't have to be the same objects or even pass
+        an equality test: they only need to be the same type and contain equal
+        `exc_obj.args`.
+        """
+        if exc is None and template is None:
+            return
+
+        if template is None:
+            self.fail(f"unexpected exception: {exc}")
+
+        if exc is None:
+            self.fail(f"expected an exception like {template!r}, got None")
+
+        if not isinstance(exc, ExceptionGroup):
+            self.assertEqual(exc.__class__, template.__class__)
+            self.assertEqual(exc.args[0], template.args[0])
+        else:
+            self.assertEqual(exc.message, template.message)
+            self.assertEqual(len(exc.exceptions), len(template.exceptions))
+            for e, t in zip(exc.exceptions, template.exceptions):
+                self.assertExceptionIsLike(e, t)
+
+
+class FloatsAreIdenticalMixin:
+    def assertFloatsAreIdentical(self, x, y):
+        """Fail unless floats x and y are identical, in the sense that:
+        (1) both x and y are nans, or
+        (2) both x and y are infinities, with the same sign, or
+        (3) both x and y are zeros, with the same sign, or
+        (4) x and y are both finite and nonzero, and x == y
+
+        """
+        msg = 'floats {!r} and {!r} are not identical'
+
+        if isnan(x) or isnan(y):
+            if isnan(x) and isnan(y):
+                return
+        elif x == y:
+            if x != 0.0:
+                return
+            # both zero; check that signs match
+            elif copysign(1.0, x) == copysign(1.0, y):
+                return
+            else:
+                msg += ': zeros have different signs'
+        self.fail(msg.format(x, y))
+
+
+class ComplexesAreIdenticalMixin(FloatsAreIdenticalMixin):
+    def assertComplexesAreIdentical(self, x, y):
+        """Fail unless complex numbers x and y have equal values and signs.
+
+        In particular, if x and y both have real (or imaginary) part
+        zero, but the zeros have different signs, this test will fail.
+
+        """
+        self.assertFloatsAreIdentical(x.real, y.real)
+        self.assertFloatsAreIdentical(x.imag, y.imag)

Lib/test/test_float.py

@@ -8,7 +8,7 @@ import time
 import unittest
 
 from test import support
-from test.support import import_helper
+from test.support.testcase import FloatsAreIdenticalMixin
 from test.test_grammar import (VALID_UNDERSCORE_LITERALS,
                                INVALID_UNDERSCORE_LITERALS)
 from math import isinf, isnan, copysign, ldexp
@@ -19,7 +19,6 @@ try:
 except ImportError:
     _testcapi = None
 
-HAVE_IEEE_754 = float.__getformat__("double").startswith("IEEE")
 INF = float("inf")
 NAN = float("nan")
 
@@ -742,8 +741,13 @@ class FormatTestCase(unittest.TestCase):
 
                 lhs, rhs = map(str.strip, line.split('->'))
                 fmt, arg = lhs.split()
-                self.assertEqual(fmt % float(arg), rhs)
-                self.assertEqual(fmt % -float(arg), '-' + rhs)
+                f = float(arg)
+                self.assertEqual(fmt % f, rhs)
+                self.assertEqual(fmt % -f, '-' + rhs)
+                if fmt != '%r':
+                    fmt2 = fmt[1:]
+                    self.assertEqual(format(f, fmt2), rhs)
+                    self.assertEqual(format(-f, fmt2), '-' + rhs)
 
     def test_issue5864(self):
         self.assertEqual(format(123.456, '.4'), '123.5')
@@ -833,7 +837,7 @@ class ReprTestCase(unittest.TestCase):
             self.assertEqual(repr(float(negs)), str(float(negs)))
 
 @support.requires_IEEE_754
-class RoundTestCase(unittest.TestCase):
+class RoundTestCase(unittest.TestCase, FloatsAreIdenticalMixin):
 
     def test_inf_nan(self):
         self.assertRaises(OverflowError, round, INF)
@@ -863,10 +867,10 @@ class RoundTestCase(unittest.TestCase):
 
     def test_small_n(self):
         for n in [-308, -309, -400, 1-2**31, -2**31, -2**31-1, -2**100]:
-            self.assertEqual(round(123.456, n), 0.0)
-            self.assertEqual(round(-123.456, n), -0.0)
-            self.assertEqual(round(1e300, n), 0.0)
-            self.assertEqual(round(1e-320, n), 0.0)
+            self.assertFloatsAreIdentical(round(123.456, n), 0.0)
+            self.assertFloatsAreIdentical(round(-123.456, n), -0.0)
+            self.assertFloatsAreIdentical(round(1e300, n), 0.0)
+            self.assertFloatsAreIdentical(round(1e-320, n), 0.0)
 
     def test_overflow(self):
         self.assertRaises(OverflowError, round, 1.6e308, -308)
@@ -1053,32 +1057,22 @@ class InfNanTest(unittest.TestCase):
         self.assertEqual(copysign(1.0, float('inf')), 1.0)
         self.assertEqual(copysign(1.0, float('-inf')), -1.0)
 
-    @unittest.skipUnless(getattr(sys, 'float_repr_style', '') == 'short',
-                         "applies only when using short float repr style")
     def test_nan_signs(self):
-        # When using the dtoa.c code, the sign of float('nan') should
-        # be predictable.
+        # The sign of float('nan') should be predictable.
         self.assertEqual(copysign(1.0, float('nan')), 1.0)
         self.assertEqual(copysign(1.0, float('-nan')), -1.0)
 
 
 fromHex = float.fromhex
 toHex = float.hex
-class HexFloatTestCase(unittest.TestCase):
+class HexFloatTestCase(FloatsAreIdenticalMixin, unittest.TestCase):
     MAX = fromHex('0x.fffffffffffff8p+1024')  # max normal
     MIN = fromHex('0x1p-1022')                # min normal
     TINY = fromHex('0x0.0000000000001p-1022') # min subnormal
     EPS = fromHex('0x0.0000000000001p0') # diff between 1.0 and next float up
 
     def identical(self, x, y):
-        # check that floats x and y are identical, or that both
-        # are NaNs
-        if isnan(x) or isnan(y):
-            if isnan(x) == isnan(y):
-                return
-        elif x == y and (x != 0.0 or copysign(1.0, x) == copysign(1.0, y)):
-            return
-        self.fail('%r not identical to %r' % (x, y))
+        self.assertFloatsAreIdentical(x, y)
 
     def test_ends(self):
         self.identical(self.MIN, ldexp(1.0, -1022))
@@ -1517,69 +1511,5 @@ class HexFloatTestCase(unittest.TestCase):
         self.assertEqual(getattr(f, 'foo', 'none'), 'bar')
 
 
-# Test PyFloat_Pack2(), PyFloat_Pack4() and PyFloat_Pack8()
-# Test PyFloat_Unpack2(), PyFloat_Unpack4() and PyFloat_Unpack8()
-BIG_ENDIAN = 0
-LITTLE_ENDIAN = 1
-EPSILON = {
-    2: 2.0 ** -11,  # binary16
-    4: 2.0 ** -24,  # binary32
-    8: 2.0 ** -53,  # binary64
-}
-
-@unittest.skipIf(_testcapi is None, 'needs _testcapi')
-class PackTests(unittest.TestCase):
-    def test_pack(self):
-        self.assertEqual(_testcapi.float_pack(2, 1.5, BIG_ENDIAN),
-                         b'>\x00')
-        self.assertEqual(_testcapi.float_pack(4, 1.5, BIG_ENDIAN),
-                         b'?\xc0\x00\x00')
-        self.assertEqual(_testcapi.float_pack(8, 1.5, BIG_ENDIAN),
-                         b'?\xf8\x00\x00\x00\x00\x00\x00')
-        self.assertEqual(_testcapi.float_pack(2, 1.5, LITTLE_ENDIAN),
-                         b'\x00>')
-        self.assertEqual(_testcapi.float_pack(4, 1.5, LITTLE_ENDIAN),
-                         b'\x00\x00\xc0?')
-        self.assertEqual(_testcapi.float_pack(8, 1.5, LITTLE_ENDIAN),
-                         b'\x00\x00\x00\x00\x00\x00\xf8?')
-
-    def test_unpack(self):
-        self.assertEqual(_testcapi.float_unpack(b'>\x00', BIG_ENDIAN),
-                         1.5)
-        self.assertEqual(_testcapi.float_unpack(b'?\xc0\x00\x00', BIG_ENDIAN),
-                         1.5)
-        self.assertEqual(_testcapi.float_unpack(b'?\xf8\x00\x00\x00\x00\x00\x00', BIG_ENDIAN),
-                         1.5)
-        self.assertEqual(_testcapi.float_unpack(b'\x00>', LITTLE_ENDIAN),
-                         1.5)
-        self.assertEqual(_testcapi.float_unpack(b'\x00\x00\xc0?', LITTLE_ENDIAN),
-                         1.5)
-        self.assertEqual(_testcapi.float_unpack(b'\x00\x00\x00\x00\x00\x00\xf8?', LITTLE_ENDIAN),
-                         1.5)
-
-    def test_roundtrip(self):
-        large = 2.0 ** 100
-        values = [1.0, 1.5, large, 1.0/7, math.pi]
-        if HAVE_IEEE_754:
-            values.extend((INF, NAN))
-        for value in values:
-            for size in (2, 4, 8,):
-                if size == 2 and value == large:
-                    # too large for 16-bit float
-                    continue
-                rel_tol = EPSILON[size]
-                for endian in (BIG_ENDIAN, LITTLE_ENDIAN):
-                    with self.subTest(value=value, size=size, endian=endian):
-                        data = _testcapi.float_pack(size, value, endian)
-                        value2 = _testcapi.float_unpack(data, endian)
-                        if isnan(value):
-                            self.assertTrue(isnan(value2), (value, value2))
-                        elif size < 8:
-                            self.assertTrue(math.isclose(value2, value, rel_tol=rel_tol),
-                                            (value, value2))
-                        else:
-                            self.assertEqual(value2, value)
-
-
 if __name__ == '__main__':
     unittest.main()