test: rename instance.killpg -> kill

The intention is to eliminate ambiguities in the `Instance` API. Make
it more like `subprocess` module (as regards `kill` and `terminate`
functions).

test/int/conftest.py

@@ -197,8 +197,8 @@ class Instance:
         with self.connection(timeout) as conn:
             return conn.eval(expr, *args)
 
-    def killpg(self):
-        """Kill entire process group"""
+    def kill(self):
+        """Kill the instance brutally with SIGKILL"""
         if self.process is None:
             # Be idempotent
             return
@@ -225,7 +225,7 @@ class Instance:
         try:
             return self.process.wait(timeout=kill_after_seconds)
         finally:
-            self.killpg()
+            self.kill()
 
     def start(self):
         if self.process:
@@ -242,9 +242,9 @@ class Instance:
         # Assert a new process group is created
         assert os.getpgid(self.process.pid) == self.process.pid
 
-    def restart(self, killpg: bool = False, drop_db: bool = False):
-        if killpg:
-            self.killpg()
+    def restart(self, kill: bool = False, drop_db: bool = False):
+        if kill:
+            self.kill()
         else:
             self.terminate()
 

test/int/test_basics.py

@@ -171,7 +171,7 @@ def test_process_management(instance: Instance):
     print(f"{instance} is still alive")
 
     # Kill the remaining child in the process group
-    instance.killpg()
+    instance.kill()
 
     # When the supervisor is killed, the orphaned child is reparented
     # to a subreaper. Pytest isn't the one, and therefore it can't do
@@ -197,8 +197,8 @@ def test_process_management(instance: Instance):
     assert pid1 == pid2
     instance.terminate()
     instance.terminate()
-    instance.killpg()
-    instance.killpg()
+    instance.kill()
+    instance.kill()
 
 
 def test_propose_eval(instance: Instance):