gh-127146: Update test skips for Emscripten 4.0.2

Lib/test/test_genericpath.py

@@ -161,7 +161,6 @@ def test_exists(self):
         self.assertIs(self.pathmodule.lexists(path=filename), True)
 
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
-    @unittest.skipIf(is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     def test_exists_fd(self):
         r, w = os.pipe()
         try:

Lib/test/test_io.py

@@ -445,9 +445,6 @@ def test_invalid_operations(self):
             self.assertRaises(exc, fp.seek, 1, self.SEEK_CUR)
             self.assertRaises(exc, fp.seek, -1, self.SEEK_END)
 
-    @unittest.skipIf(
-        support.is_emscripten, "fstat() of a pipe fd is not supported"
-    )
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def test_optional_abilities(self):
         # Test for OSError when optional APIs are not supported
@@ -502,6 +499,8 @@ class UnseekableWriter(self.MockUnseekableIO):
             (self.BytesIO, "rws"), (self.StringIO, "rws"),
         )
         for [test, abilities] in tests:
+            if test == pipe_writer and not threading_helper.can_start_thread:
+                continue
             with self.subTest(test), test() as obj:
                 readable = "r" in abilities
                 self.assertEqual(obj.readable(), readable)
@@ -3928,7 +3927,6 @@ def test_issue35928(self):
         self.assertEqual(res + f.readline(), 'foo\nbar\n')
 
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
-    @unittest.skipIf(support.is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     def test_read_non_blocking(self):
         import os
         r, w = os.pipe()
@@ -4243,9 +4241,6 @@ def test_removed_u_mode(self):
                 self.open(os_helper.TESTFN, mode)
             self.assertIn('invalid mode', str(cm.exception))
 
-    @unittest.skipIf(
-        support.is_emscripten, "fstat() of a pipe fd is not supported"
-    )
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def test_open_pipe_with_append(self):
         # bpo-27805: Ignore ESPIPE from lseek() in open().
@@ -4414,15 +4409,11 @@ def test_pickling(self):
                         with self.assertRaisesRegex(TypeError, msg):
                             pickle.dumps(f, protocol)
 
-    @unittest.skipIf(
-        support.is_emscripten, "fstat() of a pipe fd is not supported"
-    )
+    @unittest.skipIf(support.is_emscripten, "Corrupts memory")
     def test_nonblock_pipe_write_bigbuf(self):
         self._test_nonblock_pipe_write(16*1024)
 
-    @unittest.skipIf(
-        support.is_emscripten, "fstat() of a pipe fd is not supported"
-    )
+    @unittest.skipIf(support.is_emscripten, "Corrupts memory")
     def test_nonblock_pipe_write_smallbuf(self):
         self._test_nonblock_pipe_write(1024)
 

Lib/test/test_ntpath.py

@@ -940,7 +940,6 @@ def check_error(paths, expected):
         self.assertRaises(TypeError, ntpath.commonpath, ['C:\\Foo', b'Foo\\Baz'])
         self.assertRaises(TypeError, ntpath.commonpath, ['Foo', b'C:\\Foo\\Baz'])
 
-    @unittest.skipIf(is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     def test_sameopenfile(self):
         with TemporaryFile() as tf1, TemporaryFile() as tf2:
             # Make sure the same file is really the same

Lib/test/test_signal.py

@@ -253,7 +253,6 @@ def test_invalid_socket(self):
         self.assertRaises((ValueError, OSError),
                           signal.set_wakeup_fd, fd)
 
-    @unittest.skipIf(support.is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def test_set_wakeup_fd_result(self):
         r1, w1 = os.pipe()
@@ -272,7 +271,6 @@ def test_set_wakeup_fd_result(self):
         self.assertEqual(signal.set_wakeup_fd(-1), w2)
         self.assertEqual(signal.set_wakeup_fd(-1), -1)
 
-    @unittest.skipIf(support.is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     @unittest.skipUnless(support.has_socket_support, "needs working sockets.")
     def test_set_wakeup_fd_socket_result(self):
         sock1 = socket.socket()
@@ -293,7 +291,6 @@ def test_set_wakeup_fd_socket_result(self):
     # On Windows, files are always blocking and Windows does not provide a
     # function to test if a socket is in non-blocking mode.
     @unittest.skipIf(sys.platform == "win32", "tests specific to POSIX")
-    @unittest.skipIf(support.is_emscripten, "Fixed in next Emscripten release after 4.0.1")
     @unittest.skipUnless(hasattr(os, "pipe"), "requires os.pipe()")
     def test_set_wakeup_fd_blocking(self):
         rfd, wfd = os.pipe()

Tools/wasm/README.md

@@ -24,7 +24,7 @@ https://github.com/psf/webassembly for more information.
 To cross compile to the ``wasm32-emscripten`` platform you need
 [the Emscripten compiler toolchain](https://emscripten.org/), 
 a Python interpreter, and an installation of Node version 18 or newer.
-Emscripten version 3.1.73 or newer is recommended. All commands below are
+Emscripten version 4.0.2 or newer is recommended. All commands below are
 relative to a checkout of the Python repository.
 
 #### Install [the Emscripten compiler toolchain](https://emscripten.org/docs/getting_started/downloads.html)
@@ -266,7 +266,7 @@ if os.name == "posix":
 posix.uname_result(
     sysname='Emscripten',
     nodename='emscripten',
-    release='3.1.19',
+    release='4.0.2',
     version='#1',
     machine='wasm32'
 )