[Projects] Start multiple sessions via session start (#5740)

python/ray/tests/test_projects.py

@@ -165,6 +165,10 @@ def test_session_execute_default_project():
 
     assert expected_commands == commands_executed
 
+    result, mock_calls, test_dir = run_test_project(
+        "session-tests/project-pass", session_execute, ["--shell", "uptime"])
+    assert result.exit_code == 0
+
 
 def test_session_start_docker_fail():
     result, _, _ = run_test_project("session-tests/with-docker-fail",
@@ -200,3 +204,36 @@ def test_session_create_command():
         if "Starting ray job with 1 and 2" in kwargs["cmd"]:
             found_command = True
     assert found_command
+
+
+def test_session_create_multiple():
+    for args in [{"a": "*", "b": "2"}, {"a": "1", "b": "*"}]:
+        result, mock_calls, test_dir = run_test_project(
+            "session-tests/commands-test", session_start,
+            ["first", "--a", args["a"], "--b", args["b"]])
+
+        loaded_project = ray.projects.ProjectDefinition(test_dir)
+        assert result.exit_code == 0
+
+        exec_cluster_call = mock_calls["exec_cluster"]
+        commands_executed = []
+        for _, kwargs in exec_cluster_call.call_args_list:
+            commands_executed.append(kwargs["cmd"].replace(
+                "cd {}; ".format(loaded_project.working_directory()), ""))
+        assert commands_executed.count("echo \"Setting up\"") == 2
+        if args["a"] == "*":
+            assert commands_executed.count(
+                "echo \"Starting ray job with 1 and 2\"") == 1
+            assert commands_executed.count(
+                "echo \"Starting ray job with 2 and 2\"") == 1
+        if args["b"] == "*":
+            assert commands_executed.count(
+                "echo \"Starting ray job with 1 and 1\"") == 1
+            assert commands_executed.count(
+                "echo \"Starting ray job with 1 and 2\"") == 1
+
+    # Using multiple wildcards shouldn't work
+    result, mock_calls, test_dir = run_test_project(
+        "session-tests/commands-test", session_start,
+        ["first", "--a", "*", "--b", "*"])
+    assert result.exit_code == 1