Added a clone method to TreeCursor

seart-group · Sep 21, 2023 · 8fa884d · 8fa884d
1 parent 26c5113
commit 8fa884d
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Showing 4 changed files with 41 additions and 1 deletion.
diff --git a/lib/ch_usi_si_seart_treesitter_TreeCursor.cc b/lib/ch_usi_si_seart_treesitter_TreeCursor.cc
@@ -69,3 +69,19 @@ JNIEXPORT jboolean JNICALL Java_ch_usi_si_seart_treesitter_TreeCursor_gotoParent
   env->SetIntField(thisObject, _treeCursorContext1Field, cursor->context[1]);
   return result ? JNI_TRUE : JNI_FALSE;
 }
+
+JNIEXPORT jobject JNICALL Java_ch_usi_si_seart_treesitter_TreeCursor_clone(
+  JNIEnv* env, jobject thisObject) {
+  jobject treeObject = env->GetObjectField(thisObject, _treeCursorTreeField);
+  const TSTreeCursor* cursor = (const TSTreeCursor*)__getPointer(env, thisObject);
+  TSTreeCursor copy = ts_tree_cursor_copy(cursor);
+  return env->NewObject(
+    _treeCursorClass,
+    _treeCursorConstructor,
+    new TSTreeCursor(copy),
+    copy.context[0],
+    copy.context[1],
+    copy.id,
+    treeObject
+  );
+}
diff --git a/lib/ch_usi_si_seart_treesitter_TreeCursor.h b/lib/ch_usi_si_seart_treesitter_TreeCursor.h
diff --git a/src/main/java/ch/usi/si/seart/treesitter/TreeCursor.java b/src/main/java/ch/usi/si/seart/treesitter/TreeCursor.java
@@ -18,7 +18,7 @@
  * @author Ozren Dabić
  */
 @FieldDefaults(level = AccessLevel.PRIVATE, makeFinal = true)
-public class TreeCursor extends External {
+public class TreeCursor extends External implements Cloneable {
 
     int context0;
     int context1;
@@ -120,4 +120,13 @@ public void preorderTraversal(@NotNull Consumer<Node> callback) {
     public String toString() {
         return String.format("TreeCursor(id: %d, tree: %d)", id, tree.pointer);
     }
+
+    /**
+     * Clone this cursor, creating a separate, independent instance.
+     *
+     * @return a clone of this instance
+     * @since 1.5.1
+     */
+    @Override
+    public native TreeCursor clone();
 }
diff --git a/src/test/java/ch/usi/si/seart/treesitter/TreeCursorTest.java b/src/test/java/ch/usi/si/seart/treesitter/TreeCursorTest.java
@@ -1,5 +1,6 @@
 package ch.usi.si.seart.treesitter;
 
+import lombok.Cleanup;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
@@ -76,6 +77,12 @@ void testPreorderTraversal() {
         Assertions.assertEquals(17, count.get());
     }
 
+    @Test
+    void testClone() {
+        @Cleanup TreeCursor copy = cursor.clone();
+        Assertions.assertNotEquals(cursor, copy);
+    }
+
     @Test
     @SuppressWarnings("resource")
     void testWalkThrows() {