Make isNotEqualTo(boolean) to pass when actual is null

Fix #3341

assertj-core/src/main/java/org/assertj/core/internal/Booleans.java

@@ -46,14 +46,10 @@ public static Booleans instance() {
    * @param info contains information about the assertion.
    * @param actual the actual value.
    * @param expected the expected value.
-   * @throws AssertionError if the actual value is {@code null}.
-   * @throws AssertionError if the actual value is not equal to the expected one. This method will throw a
-   *           {@code org.junit.ComparisonFailure} instead if JUnit is in the classpath and the expected and actual values are not
-   *           equal.
+   * @throws AssertionError if the actual value is not equal to the expected one.
    */
   public void assertEqual(AssertionInfo info, Boolean actual, boolean expected) {
-    assertNotNull(info, actual);
-    if (actual == expected) return;
+    if (actual != null && actual == expected) return;
     throw failures.failure(info, shouldBeEqual(actual, expected, info.representation()));
   }
 
@@ -62,16 +58,10 @@ public void assertEqual(AssertionInfo info, Boolean actual, boolean expected) {
    * @param info contains information about the assertion.
    * @param actual the actual value.
    * @param other the value to compare the actual value to.
-   * @throws AssertionError if the actual value is {@code null}.
    * @throws AssertionError if the actual value is equal to the other one.
    */
   public void assertNotEqual(AssertionInfo info, Boolean actual, boolean other) {
-    assertNotNull(info, actual);
-    if (actual != other) return;
+    if (actual == null || actual != other) return;
     throw failures.failure(info, shouldNotBeEqual(actual, other));
   }
-
-  private static void assertNotNull(AssertionInfo info, Boolean actual) {
-    Objects.instance().assertNotNull(info, actual);
-  }
 }

assertj-core/src/test/java/org/assertj/core/internal/BooleansBaseTest.java

@@ -12,8 +12,10 @@
  */
 package org.assertj.core.internal;
 
+import static org.assertj.core.test.TestData.someInfo;
 import static org.mockito.Mockito.spy;
 
+import org.assertj.core.api.AssertionInfo;
 import org.junit.jupiter.api.BeforeEach;
 
 /**
@@ -25,6 +27,8 @@
  */
 public class BooleansBaseTest {
 
+  protected static final AssertionInfo INFO = someInfo();
+
   protected Failures failures;
   protected Booleans booleans;
 
@@ -35,4 +39,4 @@ public void setUp() {
     booleans.failures = failures;
   }
 
-}
+}

assertj-core/src/test/java/org/assertj/core/internal/booleans/Booleans_assertEqual_Test.java

@@ -12,13 +12,12 @@
  */
 package org.assertj.core.internal.booleans;
 
+import static java.lang.Boolean.FALSE;
 import static java.lang.Boolean.TRUE;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.assertj.core.api.Assertions.catchThrowable;
+import static java.lang.String.format;
+import static org.assertj.core.api.BDDAssertions.then;
 import static org.assertj.core.error.ShouldBeEqual.shouldBeEqual;
-import static org.assertj.core.test.TestData.someInfo;
-import static org.assertj.core.util.FailureMessages.actualIsNull;
+import static org.assertj.core.util.AssertionsUtil.expectAssertionError;
 import static org.mockito.Mockito.verify;
 
 import org.assertj.core.api.AssertionInfo;
@@ -35,24 +34,33 @@
 class Booleans_assertEqual_Test extends BooleansBaseTest {
 
   @Test
-  void should_fail_if_actual_is_null() {
-    assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> booleans.assertEqual(someInfo(), null, true))
-                                                   .withMessage(actualIsNull());
+  void should_fail_if_actual_is_null_since_the_other_argument_cannot_be_null() {
+    // GIVEN
+    Boolean actual = null;
+    // WHEN
+    AssertionError assertionError = expectAssertionError(() -> booleans.assertEqual(INFO, actual, true));
+    // THEN
+    then(assertionError).hasMessage(format("%n" +
+                                           "expected: true%n" +
+                                           " but was: null"));
   }
 
   @Test
   void should_pass_if_booleans_are_equal() {
-    booleans.assertEqual(someInfo(), TRUE, true);
+    booleans.assertEqual(INFO, true, true);
+    booleans.assertEqual(INFO, TRUE, true);
+    booleans.assertEqual(INFO, FALSE, false);
+    booleans.assertEqual(INFO, false, false);
   }
 
   @Test
   void should_fail_if_booleans_are_not_equal() {
-    AssertionInfo info = someInfo();
+    // GIVEN
+    boolean actual = TRUE;
     boolean expected = false;
-
-    Throwable error = catchThrowable(() -> booleans.assertEqual(info, TRUE, expected));
-
-    assertThat(error).isInstanceOf(AssertionError.class);
-    verify(failures).failure(info, shouldBeEqual(TRUE, expected, info.representation()));
+    // WHEN
+    expectAssertionError(() -> booleans.assertEqual(INFO, actual, expected));
+    // THEN
+    verify(failures).failure(INFO, shouldBeEqual(actual, expected, INFO.representation()));
   }
 }

assertj-core/src/test/java/org/assertj/core/internal/booleans/Booleans_assertNotEqual_Test.java

@@ -12,13 +12,10 @@
  */
 package org.assertj.core.internal.booleans;
 
+import static java.lang.Boolean.FALSE;
 import static java.lang.Boolean.TRUE;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.assertj.core.api.Assertions.catchThrowable;
 import static org.assertj.core.error.ShouldNotBeEqual.shouldNotBeEqual;
-import static org.assertj.core.test.TestData.someInfo;
-import static org.assertj.core.util.FailureMessages.actualIsNull;
+import static org.assertj.core.util.AssertionsUtil.expectAssertionError;
 import static org.mockito.Mockito.verify;
 
 import org.assertj.core.api.AssertionInfo;
@@ -35,23 +32,33 @@
 class Booleans_assertNotEqual_Test extends BooleansBaseTest {
 
   @Test
-  void should_fail_if_actual_is_null() {
-    assertThatExceptionOfType(AssertionError.class).isThrownBy(() -> booleans.assertNotEqual(someInfo(), null, false))
-                                                   .withMessage(actualIsNull());
+  void should_pass_if_actual_is_null_since_the_other_argument_cannot_be_null() {
+    booleans.assertNotEqual(INFO, null, false);
+    booleans.assertNotEqual(INFO, null, FALSE);
+    booleans.assertNotEqual(INFO, null, true);
+    booleans.assertNotEqual(INFO, null, TRUE);
   }
 
   @Test
-  void should_pass_if_bytes_are_not_equal() {
-    booleans.assertNotEqual(someInfo(), TRUE, false);
+  void should_pass_if_booleans_are_not_equal() {
+    booleans.assertNotEqual(INFO, true, false);
+    booleans.assertNotEqual(INFO, true, FALSE);
+    booleans.assertNotEqual(INFO, TRUE, false);
+    booleans.assertNotEqual(INFO, TRUE, FALSE);
+    booleans.assertNotEqual(INFO, false, true);
+    booleans.assertNotEqual(INFO, false, TRUE);
+    booleans.assertNotEqual(INFO, FALSE, true);
+    booleans.assertNotEqual(INFO, FALSE, TRUE);
   }
 
   @Test
-  void should_fail_if_bytes_are_equal() {
-    AssertionInfo info = someInfo();
-
-    Throwable error = catchThrowable(() -> booleans.assertNotEqual(info, TRUE, true));
-
-    assertThat(error).isInstanceOf(AssertionError.class);
-    verify(failures).failure(info, shouldNotBeEqual(TRUE, true));
+  void should_fail_if_booleans_are_equal() {
+    // GIVEN
+    boolean actual = TRUE;
+    boolean expected = true;
+    // WHEN
+    expectAssertionError(() -> booleans.assertNotEqual(INFO, actual, expected));
+    // THEN
+    verify(failures).failure(INFO, shouldNotBeEqual(actual, expected));
   }
 }

assertj-core/src/test/java/org/assertj/core/test/TestData.java

@@ -30,8 +30,7 @@ public final class TestData {
 
   private static final WritableAssertionInfo ASSERTION_INFO = new WritableAssertionInfo();
   private static final WritableAssertionInfo ASSERTION_INFO_AS_HEX = new WritableAssertionInfo();
-  private static final TextDescription DESCRIPTION = new TextDescription(
-                                                                         "who's the more foolish: the fool, or the fool who follows him?");
+  private static final TextDescription DESCRIPTION = new TextDescription("who's the more foolish: the fool, or the fool who follows him?");
   private static final Index INDEX = atIndex(0);
   private static final Pattern MATCH_ANYTHING = Pattern.compile(".*");