If a subprocess gets killed by an OOM killer or whatever it should respawn and raise an InternalError

jedi/evaluate/compiled/subprocess/__init__.py

@@ -10,6 +10,8 @@ goals:
 import os
 import sys
 import subprocess
+import socket
+import errno
 import weakref
 import pickle
 from functools import partial
@@ -192,7 +194,16 @@ class _CompiledSubprocess(object):
 
         data = evaluator_id, function, args, kwargs
         pickle.dump(data, self._process.stdin, protocol=_PICKLE_PROTOCOL)
+        try:
             self._process.stdin.flush()
+        except socket.error as e:
+            # Once Python2 will be removed we can just use `BrokenPipeError`.
+            if e.errno != errno.EPIPE:
+                # Not a broken pipe
+                raise
+            self.kill()
+            raise InternalError("The subprocess was killed. Maybe out of memory?")
+
         try:
             is_exception, result = _pickle_load(self._process.stdout)
         except EOFError:

test/test_api/test_environment.py

@@ -58,3 +58,16 @@ def test_error_in_environment(evaluator, Script):
     # Jedi should still work.
     def_, = Script('str').goto_definitions()
     assert def_.name == 'str'
+
+
+def test_killed_subprocess(evaluator, Script):
+    # Just kill the subprocess.
+    evaluator.compiled_subprocess._compiled_subprocess._process.kill()
+    # Since the process was terminated (and nobody knows about it) the first
+    # Jedi call fails.
+    with pytest.raises(jedi.InternalError):
+        Script('str').goto_definitions()
+
+    def_, = Script('str').goto_definitions()
+    # Jedi should now work again.
+    assert def_.name == 'str'