test: --save-signal was a bit overtested, remove the difficult one

Author: nedbat

coverage/cmdline.py

@@ -820,7 +820,7 @@ def do_help(
 
     def do_signal_save(self, _signum: int, _frame: types.FrameType | None) -> None:
         """ Signal handler to save coverage report """
-        print("Saving coverage data ...", flush=True)
+        print("Saving coverage data...", flush=True)
         self.coverage.save()
 
     def do_run(self, options: optparse.Values, args: list[str]) -> int:

tests/helpers.py

@@ -13,7 +13,6 @@
 import os
 import os.path
 import re
-import shlex
 import shutil
 import subprocess
 import sys
@@ -48,7 +47,7 @@ def _correct_encoding() -> str:
     return encoding
 
 
-def subprocess_popen(cmd: str, shell: bool=True) -> subprocess.Popen[bytes]:
+def subprocess_popen(cmd: str) -> subprocess.Popen[bytes]:
     """Run a command in a subprocess.
 
     Returns the Popen object.
@@ -67,12 +66,9 @@ def subprocess_popen(cmd: str, shell: bool=True) -> subprocess.Popen[bytes]:
     sub_env = dict(os.environ)
     sub_env["PYTHONIOENCODING"] = _correct_encoding()
 
-    if not shell:
-        cmd = shlex.split(cmd)  # type: ignore[assignment]
-
     proc = subprocess.Popen(
         cmd,
-        shell=shell,
+        shell=True,
         env=sub_env,
         stdin=subprocess.PIPE,
         stdout=subprocess.PIPE,

tests/test_process.py

@@ -15,7 +15,6 @@
 import stat
 import sys
 import textwrap
-import time
 
 from pathlib import Path
 from typing import Any
@@ -29,7 +28,7 @@
 
 from tests import testenv
 from tests.coveragetest import CoverageTest, TESTS_DIR
-from tests.helpers import re_line, re_lines, re_lines_text, subprocess_popen
+from tests.helpers import re_line, re_lines, re_lines_text
 
 
 class ProcessTest(CoverageTest):
@@ -458,37 +457,6 @@ def test_os_exit(self, patch: bool) -> None:
         else:
             assert seen < total_lines
 
-    @pytest.mark.skipif(env.WINDOWS, reason="Windows can't do --save-signal")
-    @pytest.mark.parametrize("send", [False, True])
-    def test_save_signal(self, send: bool) -> None:
-        # PyPy on Ubuntu seems to need more time for things to happen.
-        base_time = 0.0
-        if env.PYPY and env.LINUX:
-            base_time += 0.75
-        if env.METACOV:
-            base_time += 1.0
-        self.make_file("loop.py", """\
-            import time
-            print("Starting", flush=True)
-            while True:
-                time.sleep(.02)
-            """)
-        proc = subprocess_popen("coverage run --save-signal=USR1 loop.py", shell=False)
-        time.sleep(base_time + .25)
-        if send:
-            proc.send_signal(signal.SIGUSR1)
-            time.sleep(base_time + .25)
-        proc.kill()
-        proc.wait(timeout=base_time + .25)
-        stdout, _ = proc.communicate()
-        assert b"Starting" in stdout
-        if send:
-            self.assert_exists(".coverage")
-            assert b"Saving coverage data" in stdout
-        else:
-            self.assert_doesnt_exist(".coverage")
-            assert b"Saving coverage data" not in stdout
-
     def test_warnings_during_reporting(self) -> None:
         # While fixing issue #224, the warnings were being printed far too
         # often.  Make sure they're not any more.
@@ -728,24 +696,25 @@ def test_save_signal_usr1(self) -> None:
             import os
             import signal
 
-            print(f"Sending SIGUSR1 to process {os.getpid()}")
+            print(f"Sending SIGUSR1 to myself")
             os.kill(os.getpid(), signal.SIGUSR1)
             os.kill(os.getpid(), signal.SIGKILL)
 
-            print('Done and goodbye')
+            print("Done and goodbye")
             """)
-        covered_lines = 4
-        self.run_command(f"coverage run --save-signal USR1 {test_file}", status=-signal.SIGKILL)
+        out = self.run_command(
+            f"coverage run --save-signal=USR1 {test_file}",
+            status=-signal.SIGKILL,
+        )
+        # `startswith` because on Linux it also prints "Killed"
+        assert out.startswith("Sending SIGUSR1 to myself\nSaving coverage data...\n")
         self.assert_exists(".coverage")
-        data = coverage.CoverageData()
-        data.read()
-        assert line_counts(data)[test_file] == covered_lines
-        out = self.run_command("coverage report")
+        out = self.run_command("coverage report -m")
         assert out == textwrap.dedent("""\
-            Name             Stmts   Miss  Cover
-            ------------------------------------
-            dummy_hello.py       6      2    67%
-            ------------------------------------
+            Name             Stmts   Miss  Cover   Missing
+            ----------------------------------------------
+            dummy_hello.py       6      2    67%   6-8
+            ----------------------------------------------
             TOTAL                6      2    67%
             """)