Test stdio redirection with socket prewarm

kitty/prewarm.py

@@ -362,6 +362,8 @@ class SocketClosed(Exception):
 
 
 def verify_socket_creds(conn: socket.socket) -> bool:
+    # needed as abstract unix sockets used on Linux have no permissions and
+    # older BSDs ignore socket file permissions
     uid, gid = getpeereid(conn.fileno())
     return uid == os.geteuid() and gid == os.getegid()
 

kitty_tests/__init__.py

@@ -10,7 +10,7 @@ import struct
 import sys
 import termios
 import time
-from pty import CHILD, fork
+from pty import CHILD, fork, STDIN_FILENO, STDOUT_FILENO
 from unittest import TestCase
 
 from kitty.config import finalize_keys, finalize_mouse_mappings
@@ -180,9 +180,12 @@ class BaseTest(TestCase):
         s = Screen(c, lines, cols, scrollback, cell_width, cell_height, 0, c)
         return s
 
-    def create_pty(self, argv=None, cols=80, lines=100, scrollback=100, cell_width=10, cell_height=20, options=None, cwd=None, env=None):
+    def create_pty(
+            self, argv=None, cols=80, lines=100, scrollback=100, cell_width=10, cell_height=20,
+            options=None, cwd=None, env=None, stdin_fd=None, stdout_fd=None
+    ):
         self.set_options(options)
-        return PTY(argv, lines, cols, scrollback, cell_width, cell_height, cwd, env)
+        return PTY(argv, lines, cols, scrollback, cell_width, cell_height, cwd, env, stdin_fd=stdin_fd, stdout_fd=stdout_fd)
 
     def assertEqualAttributes(self, c1, c2):
         x1, y1, c1.x, c1.y = c1.x, c1.y, 0, 0
@@ -195,7 +198,10 @@ class BaseTest(TestCase):
 
 class PTY:
 
-    def __init__(self, argv=None, rows=25, columns=80, scrollback=100, cell_width=10, cell_height=20, cwd=None, env=None):
+    def __init__(
+        self, argv=None, rows=25, columns=80, scrollback=100, cell_width=10, cell_height=20,
+        cwd=None, env=None, stdin_fd=None, stdout_fd=None
+    ):
         if isinstance(argv, str):
             argv = shlex.split(argv)
         self.write_buf = b''
@@ -211,7 +217,17 @@ class PTY:
                 time.sleep(0.01)
             if cwd:
                 os.chdir(cwd)
+            if stdin_fd is not None:
+                os.dup2(stdin_fd, STDIN_FILENO)
+                os.close(stdin_fd)
+            if stdout_fd is not None:
+                os.dup2(stdout_fd, STDOUT_FILENO)
+                os.close(stdout_fd)
             os.execvpe(argv[0], argv, env or os.environ)
+        if stdin_fd is not None:
+            os.close(stdin_fd)
+        if stdout_fd is not None:
+            os.close(stdout_fd)
         os.set_blocking(self.master_fd, False)
         self.cell_width = cell_width
         self.cell_height = cell_height

kitty_tests/prewarm.py

@@ -32,11 +32,13 @@ def socket_child_main(exit_code=0):
         'test_env': os.environ.get('TEST_ENV_PASS', ''),
         'cwd': os.getcwd(),
         'font_family': get_options().font_family,
-        'cols': read_screen_size().cols,
+        'cols': read_screen_size(fd=sys.stderr.fileno()).cols,
+        'stdin_data': sys.stdin.read(),
 
         'done': 'hello',
     }
     print(json.dumps(output, indent=2), file=sys.stderr, flush=True)
+    print('testing stdout', end='')
     raise SystemExit(exit_code)
 
 # END_socket_child_main
@@ -61,7 +63,18 @@ class Prewarm(BaseTest):
             return
         env = {'TEST_ENV_PASS': 'xyz', 'KITTY_PREWARM_SOCKET': p.socket_env_var()}
         cols = 117
-        pty = self.create_pty(argv=[kitty_exe(), '+runpy', src + f'socket_child_main({exit_code})'], cols=cols, env=env, cwd=cwd)
+        stdin_r, stdin_w = os.pipe()
+        os.set_inheritable(stdin_w, False)
+        stdout_r, stdout_w = os.pipe()
+        os.set_inheritable(stdout_r, False)
+        pty = self.create_pty(
+            argv=[kitty_exe(), '+runpy', src + f'socket_child_main({exit_code})'], cols=cols, env=env, cwd=cwd,
+            stdin_fd=stdin_r, stdout_fd=stdout_w)
+        stdin_data = 'testing--stdin-read'
+        with open(stdin_w, 'w') as f:
+            f.write(stdin_data)
+        with open(stdout_r) as f:
+            stdout_data = f.read()
         status = os.waitpid(pty.child_pid, 0)[1]
         with suppress(AttributeError):
             self.assertEqual(os.waitstatus_to_exitcode(status), exit_code)
@@ -71,6 +84,8 @@ class Prewarm(BaseTest):
         self.assertEqual(output['cwd'], cwd)
         self.assertEqual(output['font_family'], 'prewarm')
         self.assertEqual(output['cols'], cols)
+        self.assertEqual(output['stdin_data'], stdin_data)
+        self.assertEqual(stdout_data, 'testing stdout')
 
     def test_prewarming(self):
         from kitty.prewarm import fork_prewarm_process