On branch edburns/dd-2758695-virtual-threads-accept-executor

modified:   src/main/java/com/github/copilot/sdk/json/CopilotClientOptions.java

- Correctly implement the semantic of "null argument to setExecutor means use the default executor."

modified:   src/test/java/com/github/copilot/sdk/ConfigCloneTest.java

- Adjust test based on defensive copy changes.

Author: edburns

src/main/java/com/github/copilot/sdk/json/CopilotClientOptions.java

@@ -264,13 +264,16 @@ public Executor getExecutor() {
      * {@code CompletableFuture} combinators instead of the default
      * {@code ForkJoinPool.commonPool()}. This allows callers to isolate SDK work
      * onto a dedicated thread pool or integrate with container-managed threading.
+     * <p>
+     * Passing {@code null} reverts to the default {@code ForkJoinPool.commonPool()}
+     * behavior.
      *
      * @param executor
-     *            the executor to use
+     *            the executor to use, or {@code null} for the default
      * @return this options instance for fluent chaining
      */
     public CopilotClientOptions setExecutor(Executor executor) {
-        this.executor = Objects.requireNonNull(executor, "executor must not be null");
+        this.executor = executor;
         return this;
     }
 

src/test/java/com/github/copilot/sdk/ConfigCloneTest.java

@@ -49,10 +49,16 @@ void copilotClientOptionsArrayIndependence() {
         original.setCliArgs(args);
 
         CopilotClientOptions cloned = original.clone();
-        cloned.getCliArgs()[0] = "--changed";
 
+        // Mutate the source array after set — should not affect original or clone
+        args[0] = "--changed";
+
+        assertEquals("--flag1", original.getCliArgs()[0]);
+        assertEquals("--flag1", cloned.getCliArgs()[0]);
+
+        // getCliArgs() returns a copy, so mutating it should not affect internals
+        original.getCliArgs()[0] = "--mutated";
         assertEquals("--flag1", original.getCliArgs()[0]);
-        assertEquals("--changed", cloned.getCliArgs()[0]);
     }
 
     @Test
@@ -64,12 +70,15 @@ void copilotClientOptionsEnvironmentIndependence() {
 
         CopilotClientOptions cloned = original.clone();
 
-        // Mutate the original environment map to test independence
+        // Mutate the source map after set — should not affect original or clone
         env.put("KEY2", "value2");
 
-        // The cloned config should be unaffected by mutations to the original map
+        assertEquals(1, original.getEnvironment().size());
         assertEquals(1, cloned.getEnvironment().size());
-        assertEquals(2, original.getEnvironment().size());
+
+        // getEnvironment() returns a copy, so mutating it should not affect internals
+        original.getEnvironment().put("KEY3", "value3");
+        assertEquals(1, original.getEnvironment().size());
     }
 
     @Test