Add TypeScript declaration and tests for mat_clone() method

src/types/opencv/Mat.ts

@@ -787,6 +787,12 @@ export declare class Mat extends EmscriptenEmbindInstance {
    */
   public clone(): Mat;
 
+  /**
+   *   Creates a deep copy of the Mat with independent data buffer.
+   *   This method ensures the copied Mat has its own data that is independent of the original.
+   */
+  public mat_clone(): Mat;
+
   /**
    *   The method makes a new header for the specified matrix column and returns it. This is an O(1)
    * operation, regardless of the matrix size. The underlying data of the new matrix is shared with the

test/Mat.test.ts

@@ -75,4 +75,95 @@ describe("Mat", () => {
       throw translateException(err);
     }
   });
+
+  it("should test Mat.clone() behavior to reproduce issue #85", async () => {
+    try {
+      console.log("Testing Mat.clone() behavior...");
+
+      // Create a 1x1 matrix with zeros
+      const m1 = cv.Mat.zeros(1, 1, cv.CV_8U);
+      const m2 = m1.clone();
+
+      // Check initial values
+      const m1_initial = m1.ucharAt(0);
+      const m2_initial = m2.ucharAt(0);
+      console.log(`Initial: m1 = ${m1_initial}, m2 = ${m2_initial}`);
+
+      // Modify m1 through its data array
+      m1.data[0] = 1;
+
+      // Check values after modification
+      const m1_after = m1.ucharAt(0);
+      const m2_after = m2.ucharAt(0);
+      console.log(`After modifying m1.data[0]: m1 = ${m1_after}, m2 = ${m2_after}`);
+
+      // This test documents the current buggy behavior of clone()
+      expect(m1_after).toBe(1);
+      expect(m2_after).toBe(1); // Bug: clone() shares data
+
+      m1.delete();
+      m2.delete();
+    } catch (err) {
+      throw translateException(err);
+    }
+  });
+
+  it("should test Mat.mat_clone() fixes the clone issue #85", async () => {
+    try {
+      console.log("Testing Mat.mat_clone() fix...");
+
+      // Create a 1x1 matrix with zeros
+      const m1 = cv.Mat.zeros(1, 1, cv.CV_8U);
+      const m2 = m1.mat_clone();
+
+      // Check initial values
+      const m1_initial = m1.ucharAt(0);
+      const m2_initial = m2.ucharAt(0);
+      console.log(`Initial: m1 = ${m1_initial}, m2 = ${m2_initial}`);
+
+      // Modify m1 through its data array
+      m1.data[0] = 1;
+
+      // Check values after modification
+      const m1_after = m1.ucharAt(0);
+      const m2_after = m2.ucharAt(0);
+      console.log(`After modifying m1.data[0]: m1 = ${m1_after}, m2 = ${m2_after}`);
+
+      // Expected behavior: m1 = 1, m2 = 0 (independent copies)
+      expect(m1_after).toBe(1);
+      expect(m2_after).toBe(0); // Fixed: mat_clone() creates independent copies
+
+      m1.delete();
+      m2.delete();
+    } catch (err) {
+      throw translateException(err);
+    }
+  });
+
+  it("should test Mat.mat_clone() works with different Mat sizes and types", async () => {
+    try {
+      console.log("Testing Mat.mat_clone() with different types...");
+
+      // Test with a 3x3 matrix of different type
+      const m1 = cv.Mat.ones(3, 3, cv.CV_32F);
+      const m2 = m1.mat_clone();
+
+      // Verify dimensions and type are preserved
+      expect(m2.rows).toBe(m1.rows);
+      expect(m2.cols).toBe(m1.cols);
+      expect(m2.type()).toBe(m1.type());
+
+      // Modify first element of m1
+      m1.data32F[0] = 42.5;
+
+      // Check that m2 is not affected
+      expect(m1.data32F[0]).toBe(42.5);
+      expect(m2.data32F[0]).toBe(1.0); // Should remain original value
+
+      m1.delete();
+      m2.delete();
+    } catch (err) {
+      throw translateException(err);
+    }
+  });
 });