change call_until() signature so that it can be used with lambda

psutil/tests/__init__.py

@@ -472,7 +472,7 @@ def spawn_zombie():
             zpid = int(conn.recv(1024))
             _pids_started.add(zpid)
             zombie = psutil.Process(zpid)
-            call_until(zombie.status, "ret == psutil.STATUS_ZOMBIE")
+            call_until(lambda: zombie.status() == psutil.STATUS_ZOMBIE)
             return (parent, zombie)
         finally:
             conn.close()
@@ -792,12 +792,10 @@ def wait_for_file(fname, delete=True, empty=False):
     timeout=GLOBAL_TIMEOUT,
     interval=0.001,
 )
-def call_until(fun, expr):
-    """Keep calling function for timeout secs and exit if eval()
-    expression is True.
-    """
+def call_until(fun):
+    """Keep calling function until it evaluates to True."""
     ret = fun()
-    assert eval(expr)  # noqa
+    assert ret
     return ret
 
 

psutil/tests/test_linux.py

@@ -1953,7 +1953,7 @@ def test_open_files_file_gone(self):
         files = p.open_files()
         with open(self.get_testfn(), 'w'):
             # give the kernel some time to see the new file
-            call_until(p.open_files, "len(ret) != %i" % len(files))
+            call_until(lambda: len(p.open_files()) != len(files))
             with mock.patch(
                 'psutil._pslinux.os.readlink',
                 side_effect=OSError(errno.ENOENT, ""),
@@ -1977,7 +1977,7 @@ def test_open_files_fd_gone(self):
         files = p.open_files()
         with open(self.get_testfn(), 'w'):
             # give the kernel some time to see the new file
-            call_until(p.open_files, "len(ret) != %i" % len(files))
+            call_until(lambda: len(p.open_files()) != len(files))
             patch_point = 'builtins.open' if PY3 else '__builtin__.open'
             with mock.patch(
                 patch_point, side_effect=IOError(errno.ENOENT, "")
@@ -1993,7 +1993,7 @@ def test_open_files_enametoolong(self):
         files = p.open_files()
         with open(self.get_testfn(), 'w'):
             # give the kernel some time to see the new file
-            call_until(p.open_files, "len(ret) != %i" % len(files))
+            call_until(lambda: len(p.open_files()) != len(files))
             patch_point = 'psutil._pslinux.os.readlink'
             with mock.patch(
                 patch_point, side_effect=OSError(errno.ENAMETOOLONG, "")

psutil/tests/test_process.py

@@ -988,7 +988,7 @@ def test_cwd_2(self):
             ),
         ]
         p = self.spawn_psproc(cmd)
-        call_until(p.cwd, "ret == os.path.dirname(os.getcwd())")
+        call_until(lambda: p.cwd() == os.path.dirname(os.getcwd()))
 
     @unittest.skipIf(not HAS_CPU_AFFINITY, 'not supported')
     def test_cpu_affinity(self):
@@ -1075,7 +1075,8 @@ def test_open_files(self):
             f.write(b'x' * 1024)
             f.flush()
             # give the kernel some time to see the new file
-            files = call_until(p.open_files, "len(ret) != %i" % len(files))
+            call_until(lambda: len(p.open_files()) != len(files))
+            files = p.open_files()
             filenames = [os.path.normcase(x.path) for x in files]
             assert os.path.normcase(testfn) in filenames
             if LINUX:
@@ -1399,7 +1400,7 @@ def assert_raises_nsp(fun, fun_name):
         p.terminate()
         p.wait()
         if WINDOWS:  # XXX
-            call_until(psutil.pids, "%s not in ret" % p.pid)
+            call_until(lambda: p.pid not in psutil.pids())
         self.assertProcessGone(p)
 
         ns = process_namespace(p)

psutil/tests/test_testutils.py

@@ -166,8 +166,7 @@ def test_wait_for_file_no_delete(self):
         assert os.path.exists(testfn)
 
     def test_call_until(self):
-        ret = call_until(lambda: 1, "ret == 1")
-        assert ret == 1
+        call_until(lambda: 1)
 
 
 class TestFSTestUtils(PsutilTestCase):