test/java/util/Map/Defaults.java

rev 8947 : 8030016: HashMap.computeIfAbsent generates spurious access event
Reviewed-by: duke

@@ -78,39 +78,47 @@
         assertNull(map.getOrDefault(EXTRA_KEY, null), "null not returned as default");
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=true keys=withNull values=withNull")
     public void testPutIfAbsentNulls(String description, Map<IntegerEnum, String> map) {
+        // null -> null
         assertTrue(map.containsKey(null), "null key absent");
         assertNull(map.get(null), "value not null");
         assertNull(map.putIfAbsent(null, EXTRA_VALUE), "previous not null");
+        // null -> EXTRA_VALUE
         assertTrue(map.containsKey(null), "null key absent");
         assertSame(map.get(null), EXTRA_VALUE, "unexpected value");
         assertSame(map.putIfAbsent(null, null), EXTRA_VALUE, "previous not expected value");
         assertTrue(map.containsKey(null), "null key absent");
         assertSame(map.get(null), EXTRA_VALUE, "unexpected value");
         assertSame(map.remove(null), EXTRA_VALUE, "removed unexpected value");
+        // null -> <absent>
 
         assertFalse(map.containsKey(null), description + ": key present after remove");
         assertNull(map.putIfAbsent(null, null), "previous not null");
+        // null -> null
         assertTrue(map.containsKey(null), "null key absent");
         assertNull(map.get(null), "value not null");
         assertNull(map.putIfAbsent(null, EXTRA_VALUE), "previous not null");
         assertSame(map.get(null), EXTRA_VALUE, "value not expected");
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=true keys=all values=all")
     public void testPutIfAbsent(String description, Map<IntegerEnum, String> map) {
+        // 1 -> 1
         assertTrue(map.containsKey(KEYS[1]));
         Object expected = map.get(KEYS[1]);
         assertTrue(null == expected || expected == VALUES[1]);
         assertSame(map.putIfAbsent(KEYS[1], EXTRA_VALUE), expected);
         assertSame(map.get(KEYS[1]), expected);
 
+        // EXTRA_KEY -> <absent>
         assertFalse(map.containsKey(EXTRA_KEY));
         assertSame(map.putIfAbsent(EXTRA_KEY, EXTRA_VALUE), null);
         assertSame(map.get(EXTRA_KEY), EXTRA_VALUE);
+        assertSame(map.putIfAbsent(EXTRA_KEY, VALUES[2]), EXTRA_VALUE);
+        assertSame(map.get(EXTRA_KEY), EXTRA_VALUE);
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=all keys=all values=all")
     public void testForEach(String description, Map<IntegerEnum, String> map) {
         IntegerEnum[] EACH_KEY = new IntegerEnum[map.size()];

@@ -266,27 +274,45 @@
         assertSame(map.get(EXTRA_KEY), EXTRA_VALUE);
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=true keys=withNull values=withNull")
     public void testComputeIfAbsentNulls(String description, Map<IntegerEnum, String> map) {
+        // null -> null
+        assertTrue(map.containsKey(null), "null key absent");
+        assertNull(map.get(null), "value not null");
+        assertSame(map.computeIfAbsent(null, (k) -> null), null,  "not expected result");
         assertTrue(map.containsKey(null), "null key absent");
         assertNull(map.get(null), "value not null");
-        assertSame(map.computeIfAbsent(null, (k) -> EXTRA_VALUE), EXTRA_VALUE, description);
-        assertSame(map.get(null), EXTRA_VALUE, description);
+        assertSame(map.computeIfAbsent(null, (k) -> EXTRA_VALUE), EXTRA_VALUE, "not mapped to result");
+        // null -> EXTRA_VALUE
+        assertTrue(map.containsKey(null), "null key absent");
+        assertSame(map.get(null), EXTRA_VALUE,  "not expected value");
+        assertSame(map.remove(null), EXTRA_VALUE, "removed unexpected value");
+        // null -> <absent>
+        assertFalse(map.containsKey(null), "null key present");
+        assertSame(map.computeIfAbsent(null, (k) -> EXTRA_VALUE), EXTRA_VALUE, "not mapped to result");
+        // null -> EXTRA_VALUE
+        assertTrue(map.containsKey(null), "null key absent");
+        assertSame(map.get(null), EXTRA_VALUE,  "not expected value");
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=true keys=all values=all")
     public void testComputeIfAbsent(String description, Map<IntegerEnum, String> map) {
+        // 1 -> 1
         assertTrue(map.containsKey(KEYS[1]));
         Object expected = map.get(KEYS[1]);
         assertTrue(null == expected || expected == VALUES[1], description + String.valueOf(expected));
         expected = (null == expected) ? EXTRA_VALUE : expected;
         assertSame(map.computeIfAbsent(KEYS[1], (k) -> EXTRA_VALUE), expected, description);
         assertSame(map.get(KEYS[1]), expected, description);
 
+        // EXTRA_KEY -> <absent>
+        assertFalse(map.containsKey(EXTRA_KEY));
+        assertNull(map.computeIfAbsent(EXTRA_KEY, (k) -> null));
         assertFalse(map.containsKey(EXTRA_KEY));
         assertSame(map.computeIfAbsent(EXTRA_KEY, (k) -> EXTRA_VALUE), EXTRA_VALUE);
+        // EXTRA_KEY -> EXTRA_VALUE
         assertSame(map.get(EXTRA_KEY), EXTRA_VALUE);
     }
 
     @Test(dataProvider = "Map<IntegerEnum,String> rw=true keys=all values=all")
     public void testComputeIfAbsentNullFunction(String description, Map<IntegerEnum, String> map) {