Fix assertEquals() if toString() returns null (junit-team#1454)

Fixes junit-team#1453
RahulNagekar · May 19, 2017 · a81c5e2 · a81c5e2
1 parent d07ed0b
commit a81c5e2
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diff --git a/src/main/java/org/junit/Assert.java b/src/main/java/org/junit/Assert.java
@@ -842,7 +842,7 @@ static String format(String message, Object expected, Object actual) {
         }
         String expectedString = String.valueOf(expected);
         String actualString = String.valueOf(actual);
-        if (expectedString.equals(actualString)) {
+        if (equalsRegardingNull(expectedString, actualString)) {
             return formatted + "expected: "
                     + formatClassAndValue(expected, expectedString)
                     + " but was: " + formatClassAndValue(actual, actualString);

diff --git a/src/test/java/org/junit/tests/assertion/AssertionTest.java b/src/test/java/org/junit/tests/assertion/AssertionTest.java
@@ -717,6 +717,27 @@ public void stringNullAndNullWorksToo() {
         assertEquals("null", null);
     }
 
+    private static class NullToString {
+        @Override
+        public String toString() {
+            return null;
+        }
+    }
+
+    @Test
+    public void nullToString() {
+        try {
+            assertEquals(new NullToString(), new NullToString());
+        } catch (AssertionError e) {
+            assertEquals("expected: org.junit.tests.assertion.AssertionTest$NullToString<null> but "
+                            + "was: org.junit.tests.assertion.AssertionTest$NullToString<null>",
+                    e.getMessage());
+            return;
+        }
+
+        fail("AssertionError expected");
+    }
+
     @Test(expected = AssertionError.class)
     public void compareBigDecimalAndInteger() {
         final BigDecimal bigDecimal = new BigDecimal("1.2");