Expose Context.empty() as building block for creating custom root contexts

components/context/src/main/java/datadog/context/Context.java

@@ -36,6 +36,15 @@
  * @see ContextKey
  */
 public interface Context {
+  /**
+   * Returns the empty context.
+   *
+   * @return the context containing no values at all.
+   */
+  static Context empty() {
+    return EmptyContext.INSTANCE;
+  }
+
   /**
    * Returns the root context.
    *

components/context/src/test/java/datadog/context/ContextTest.java

@@ -1,5 +1,6 @@
 package datadog.context;
 
+import static datadog.context.Context.empty;
 import static datadog.context.Context.root;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -21,6 +22,17 @@ class ContextTest {
   static final ContextKey<Float> FLOAT_KEY = ContextKey.named("float-key");
   static final ContextKey<Long> LONG_KEY = ContextKey.named("long-key");
 
+  @Test
+  void testEmpty() {
+    // Test empty is always the same
+    Context empty = empty();
+    assertEquals(empty, empty(), "Empty context should be consistent");
+    // Test empty is not mutated
+    String stringValue = "value";
+    empty.with(STRING_KEY, stringValue);
+    assertEquals(empty, empty(), "Empty context should be immutable");
+  }
+
   @Test
   void testRoot() {
     // Test root is always the same