Refactor files to be in correctly nested packages (#6120)

src/test/java/com/thealgorithms/matrix/MatrixTransposeTest.java

@@ -0,0 +1,33 @@
+package com.thealgorithms.matrix;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.stream.Stream;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+public class MatrixTransposeTest {
+
+    private static Stream<Arguments> provideValidMatrixTestCases() {
+        return Stream.of(Arguments.of(new int[][] {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}, new int[][] {{1, 4, 7}, {2, 5, 8}, {3, 6, 9}}, "Transpose of square matrix"), Arguments.of(new int[][] {{1, 2}, {3, 4}, {5, 6}}, new int[][] {{1, 3, 5}, {2, 4, 6}}, "Transpose of rectangular matrix"),
+            Arguments.of(new int[][] {{1, 2, 3}}, new int[][] {{1}, {2}, {3}}, "Transpose of single-row matrix"), Arguments.of(new int[][] {{1}, {2}, {3}}, new int[][] {{1, 2, 3}}, "Transpose of single-column matrix"));
+    }
+
+    private static Stream<Arguments> provideInvalidMatrixTestCases() {
+        return Stream.of(Arguments.of(new int[0][0], "Empty matrix should throw IllegalArgumentException"), Arguments.of(null, "Null matrix should throw IllegalArgumentException"));
+    }
+
+    @ParameterizedTest(name = "Test case {index}: {2}")
+    @MethodSource("provideValidMatrixTestCases")
+    void testValidMatrixTranspose(int[][] input, int[][] expected, String description) {
+        assertArrayEquals(expected, MatrixTranspose.transpose(input), description);
+    }
+
+    @ParameterizedTest(name = "Test case {index}: {1}")
+    @MethodSource("provideInvalidMatrixTestCases")
+    void testInvalidMatrixTranspose(int[][] input, String description) {
+        assertThrows(IllegalArgumentException.class, () -> MatrixTranspose.transpose(input), description);
+    }
+}