[SPARK-58721][K8S] Add tests for ClientArguments.fromCommandLineArgs

resource-managers/kubernetes/core/src/test/scala/org/apache/spark/deploy/k8s/submit/ClientArgumentsSuite.scala

@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.spark.deploy.k8s.submit
+
+import org.apache.spark.SparkFunSuite
+
+class ClientArgumentsSuite extends SparkFunSuite {
+
+  test("fromCommandLineArgs parses primary Java resource") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--primary-java-resource", "local:///path/to/app.jar", "--main-class", "my.Main"))
+    assert(args.mainAppResource === JavaMainAppResource(Some("local:///path/to/app.jar")))
+    assert(args.mainClass === "my.Main")
+    assert(args.driverArgs === Array.empty[String])
+    assert(args.proxyUser === None)
+  }
+
+  test("fromCommandLineArgs parses primary Python file") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--primary-py-file", "local:///path/to/app.py", "--main-class", "org.Main"))
+    assert(args.mainAppResource === PythonMainAppResource("local:///path/to/app.py"))
+  }
+
+  test("fromCommandLineArgs parses primary R file") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--primary-r-file", "local:///path/to/app.R", "--main-class", "org.Main"))
+    assert(args.mainAppResource === RMainAppResource("local:///path/to/app.R"))
+  }
+
+  test("fromCommandLineArgs defaults main app resource when none is specified") {
+    val args = ClientArguments.fromCommandLineArgs(Array("--main-class", "my.Main"))
+    assert(args.mainAppResource === JavaMainAppResource(None))
+  }
+
+  test("fromCommandLineArgs collects repeated --arg values in order") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--main-class", "my.Main", "--arg", "a", "--arg", "b", "--arg", "c"))
+    assert(args.driverArgs === Array("a", "b", "c"))
+  }
+
+  test("fromCommandLineArgs parses proxy user") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--main-class", "my.Main", "--proxy-user", "alice"))
+    assert(args.proxyUser === Some("alice"))
+  }
+
+  test("fromCommandLineArgs uses the last --main-class when specified more than once") {
+    val args = ClientArguments.fromCommandLineArgs(
+      Array("--main-class", "first.Main", "--main-class", "second.Main"))
+    assert(args.mainClass === "second.Main")
+  }
+
+  test("fromCommandLineArgs throws when --main-class is missing") {
+    val thrown = intercept[IllegalArgumentException] {
+      ClientArguments.fromCommandLineArgs(Array("--arg", "a"))
+    }
+    assert(thrown.getMessage.contains("Main class must be specified via --main-class"))
+  }
+
+  test("fromCommandLineArgs throws when given no arguments at all") {
+    val thrown = intercept[IllegalArgumentException] {
+      ClientArguments.fromCommandLineArgs(Array.empty)
+    }
+    assert(thrown.getMessage.contains("Main class must be specified via --main-class"))
+  }
+
+  test("fromCommandLineArgs throws on an unrecognized flag") {
+    val thrown = intercept[RuntimeException] {
+      ClientArguments.fromCommandLineArgs(
+        Array("--unknown-flag", "value", "--main-class", "my.Main"))
+    }
+    assert(thrown.getMessage.contains("Unknown arguments: --unknown-flag value"))
+  }
+
+  test("fromCommandLineArgs throws on a trailing flag with no value") {
+    val thrown = intercept[RuntimeException] {
+      ClientArguments.fromCommandLineArgs(Array("--main-class", "my.Main", "--arg"))
+    }
+    assert(thrown.getMessage.contains("Unknown arguments: --arg"))
+  }
+}