diff --git a/metricbeat/module/system/test_system.py b/metricbeat/module/system/test_system.py
index cc6b731b113..82e59e71af4 100644
--- a/metricbeat/module/system/test_system.py
+++ b/metricbeat/module/system/test_system.py
@@ -392,41 +392,85 @@ def test_process(self):
         self.assertGreater(len(output), 0)
 
         found_cmdline = False
-        found_env = False
+        for evt in output:
+            process = evt["system"]["process"]
+            found_cmdline |= "cmdline" in process
+
+            # Remove 'env' prior to checking documented fields because its keys are dynamic.
+            process.pop("env", None)
+            self.assert_fields_are_documented(evt)
+
+            # Remove optional keys.
+            process.pop("cgroup", None)
+            process.pop("fd", None)
+            process.pop("cmdline", None)
+
+            self.assertCountEqual(SYSTEM_PROCESS_FIELDS, process.keys())
+
+        self.assertTrue(found_cmdline, "cmdline not found in any process events")
+
+    @unittest.skipUnless(re.match("(?i)linux|darwin|freebsd", sys.platform), "os")
+    def test_process_unix(self):
+        """
+        Test system/process output for fields specific of unix systems.
+        """
+        import getpass
+
+        self.render_config_template(
+            modules=[{
+                "name": "system",
+                "metricsets": ["process"],
+                "period": "5s",
+                "extras": {
+                    "process.env.whitelist": ["PATH"],
+                    "process.include_cpu_ticks": True,
+
+                    # Remove 'percpu' prior to checking documented fields because its keys are dynamic.
+                    "process.include_per_cpu": False,
+                },
+            }],
+            # Some info is only guaranteed in processes with permissions, check
+            # only on own processes.
+            processors=[{
+                "drop_event": {
+                    "when": "not.equals.user.name: " + getpass.getuser(),
+                },
+            }],
+        )
+        proc = self.start_beat()
+        self.wait_until(lambda: self.output_lines() > 0)
+        proc.check_kill_and_wait()
+        self.assert_no_logged_warnings()
+
+        output = self.read_output_json()
+        self.assertGreater(len(output), 0)
+
         found_fd = False
+        found_env = False
         found_cwd = not sys.platform.startswith("linux")
         for evt in output:
+            found_cwd |= "working_directory" in evt["process"]
+
             process = evt["system"]["process"]
+            found_fd |= "fd" in process
+            found_env |= "env" in process
 
             # Remove 'env' prior to checking documented fields because its keys are dynamic.
             env = process.pop("env", None)
-            if env is not None:
-                found_env = True
-
             self.assert_fields_are_documented(evt)
 
             # Remove optional keys.
             process.pop("cgroup", None)
-            cmdline = process.pop("cmdline", None)
-            if cmdline is not None:
-                found_cmdline = True
-            fd = process.pop("fd", None)
-            if fd is not None:
-                found_fd = True
-            cwd = process.pop("cwd", None)
-            if cwd is not None:
-                found_cwd = True
+            process.pop("cmdline", None)
+            process.pop("fd", None)
 
             self.assertCountEqual(SYSTEM_PROCESS_FIELDS, process.keys())
 
-        self.assertTrue(found_cmdline, "cmdline not found in any process events")
-
-        if sys.platform.startswith("linux") or sys.platform.startswith("freebsd"):
+        if not sys.platform.startswith("darwin"):
             self.assertTrue(found_fd, "fd not found in any process events")
 
-        if sys.platform.startswith("linux") or sys.platform.startswith("freebsd")\
-                or sys.platform.startswith("darwin"):
-            self.assertTrue(found_env, "env not found in any process events")
+        self.assertTrue(found_env, "env not found in any process events")
+        self.assertTrue(found_cwd, "working_directory not found in any process events")
 
     @unittest.skipUnless(re.match("(?i)win|linux|darwin|freebsd", sys.platform), "os")
     def test_process_metricbeat(self):