bpo-36686: Improve the documentation of the std* params in loop.subprocess_exec (GH-13586)

https://bugs.python.org/issue36686

1 files changed, 90 insertions, 0 deletions

diff --git a/Lib/test/test_asyncio/test_subprocess.py b/Lib/test/test_asyncio/test_subprocess.py
index 551974a..f1ab039 100644
--- a/Lib/test/test_asyncio/test_subprocess.py
+++ b/Lib/test/test_asyncio/test_subprocess.py
@@ -335,6 +335,63 @@ class SubprocessMixin:
         self.assertEqual(output.rstrip(), b'0')
         self.assertEqual(exitcode, 0)
 
+    def test_devnull_input(self):
+
+        async def empty_input():
+            code = 'import sys; data = sys.stdin.read(); print(len(data))'
+            proc = await asyncio.create_subprocess_exec(
+                                          sys.executable, '-c', code,
+                                          stdin=asyncio.subprocess.DEVNULL,
+                                          stdout=asyncio.subprocess.PIPE,
+                                          stderr=asyncio.subprocess.PIPE,
+                                          close_fds=False,
+                                          loop=self.loop)
+            stdout, stderr = await proc.communicate()
+            exitcode = await proc.wait()
+            return (stdout, exitcode)
+
+        output, exitcode = self.loop.run_until_complete(empty_input())
+        self.assertEqual(output.rstrip(), b'0')
+        self.assertEqual(exitcode, 0)
+
+    def test_devnull_output(self):
+
+        async def empty_output():
+            code = 'import sys; data = sys.stdin.read(); print(len(data))'
+            proc = await asyncio.create_subprocess_exec(
+                                          sys.executable, '-c', code,
+                                          stdin=asyncio.subprocess.PIPE,
+                                          stdout=asyncio.subprocess.DEVNULL,
+                                          stderr=asyncio.subprocess.PIPE,
+                                          close_fds=False,
+                                          loop=self.loop)
+            stdout, stderr = await proc.communicate(b"abc")
+            exitcode = await proc.wait()
+            return (stdout, exitcode)
+
+        output, exitcode = self.loop.run_until_complete(empty_output())
+        self.assertEqual(output, None)
+        self.assertEqual(exitcode, 0)
+
+    def test_devnull_error(self):
+
+        async def empty_error():
+            code = 'import sys; data = sys.stdin.read(); print(len(data))'
+            proc = await asyncio.create_subprocess_exec(
+                                          sys.executable, '-c', code,
+                                          stdin=asyncio.subprocess.PIPE,
+                                          stdout=asyncio.subprocess.PIPE,
+                                          stderr=asyncio.subprocess.DEVNULL,
+                                          close_fds=False,
+                                          loop=self.loop)
+            stdout, stderr = await proc.communicate(b"abc")
+            exitcode = await proc.wait()
+            return (stderr, exitcode)
+
+        output, exitcode = self.loop.run_until_complete(empty_error())
+        self.assertEqual(output, None)
+        self.assertEqual(exitcode, 0)
+
     def test_cancel_process_wait(self):
         # Issue #23140: cancel Process.wait()
 
@@ -531,6 +588,39 @@ class SubprocessMixin:
         with self.assertWarns(DeprecationWarning):
             subprocess.Process(transp, proto, loop=self.loop)
 
+    def test_create_subprocess_exec_text_mode_fails(self):
+        async def execute():
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_exec(sys.executable,
+                                                        text=True)
+
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_exec(sys.executable,
+                                                        encoding="utf-8")
+
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_exec(sys.executable,
+                                                        errors="strict")
+
+        self.loop.run_until_complete(execute())
+
+    def test_create_subprocess_shell_text_mode_fails(self):
+
+        async def execute():
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_shell(sys.executable,
+                                                         text=True)
+
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_shell(sys.executable,
+                                                         encoding="utf-8")
+
+            with self.assertRaises(ValueError):
+                await subprocess.create_subprocess_shell(sys.executable,
+                                                         errors="strict")
+
+        self.loop.run_until_complete(execute())
+
 
 if sys.platform != 'win32':
     # Unix