Compare for equality, not approximate equality within a tolerance of 0.0.

cpovirk · Google Java Core Libraries · commit 8dac907542af · 2024-07-03T14:17:33.000-07:00
IIRC, the behavior of the two differs only for:
- comparing NaN to itself
- comparing either infinity to itself
- comparing positive zero to negative zero

And as best I can tell, the only one of those that has any chance of coming up in these tests is the zero case. And, as best I can tell, in those cases, we actively want to test that we're returning positive zero, not negative zero. So let's test for that, and let's simplify the code in doing so.

(followup to cl/649135877; "followup" to cl/108355695, which ported these assertions from JUnit, known for steering users away from exact-equality comparisons)

RELNOTES=n/a
PiperOrigin-RevId: 649195688
diff --git a/android/guava-tests/test/com/google/common/math/PairedStatsAccumulatorTest.java b/android/guava-tests/test/com/google/common/math/PairedStatsAccumulatorTest.java
@@ -179,10 +179,8 @@ public void testPopulationCovariance() {
     assertThrows(
         IllegalStateException.class,
         () -> emptyAccumulatorByAddAllEmptyPairedStats.populationCovariance());
-    assertThat(oneValueAccumulator.populationCovariance()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyPairedStats.populationCovariance())
-        .isWithin(0.0)
-        .of(0.0);
+    assertThat(oneValueAccumulator.populationCovariance()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyPairedStats.populationCovariance()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationCovariance())
         .isWithin(ALLOWED_ERROR)
         .of(TWO_VALUES_SUM_OF_PRODUCTS_OF_DELTAS / 2);
diff --git a/android/guava-tests/test/com/google/common/math/PairedStatsTest.java b/android/guava-tests/test/com/google/common/math/PairedStatsTest.java
@@ -89,7 +89,7 @@ public void testYStats() {
 
   public void testPopulationCovariance() {
     assertThrows(IllegalStateException.class, () -> EMPTY_PAIRED_STATS.populationCovariance());
-    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isEqualTo(0.0);
     assertThat(createSingleStats(Double.POSITIVE_INFINITY, 1.23).populationCovariance()).isNaN();
     assertThat(createSingleStats(Double.NEGATIVE_INFINITY, 1.23).populationCovariance()).isNaN();
     assertThat(createSingleStats(Double.NaN, 1.23).populationCovariance()).isNaN();
diff --git a/android/guava-tests/test/com/google/common/math/StatsAccumulatorTest.java b/android/guava-tests/test/com/google/common/math/StatsAccumulatorTest.java
@@ -269,9 +269,9 @@ public void testMean() {
   }
 
   public void testSum() {
-    assertThat(emptyAccumulator.sum()).isWithin(0.0).of(0.0);
-    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isWithin(0.0).of(0.0);
-    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isWithin(0.0).of(0.0);
+    assertThat(emptyAccumulator.sum()).isEqualTo(0.0);
+    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isEqualTo(0.0);
+    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isEqualTo(0.0);
     assertThat(oneValueAccumulator.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
     assertThat(oneValueAccumulatorByAddAllEmptyStats.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
     assertThat(twoValuesAccumulator.sum()).isWithin(ALLOWED_ERROR).of(TWO_VALUES_MEAN * 2);
@@ -317,8 +317,8 @@ public void testPopulationVariance() {
         () -> emptyAccumulatorByAddAllEmptyIterable.populationVariance());
     assertThrows(
         IllegalStateException.class, () -> emptyAccumulatorByAddAllEmptyStats.populationVariance());
-    assertThat(oneValueAccumulator.populationVariance()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationVariance()).isWithin(0.0).of(0.0);
+    assertThat(oneValueAccumulator.populationVariance()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationVariance()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationVariance())
         .isWithin(ALLOWED_ERROR)
         .of(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2);
@@ -392,10 +392,8 @@ public void testPopulationStandardDeviation() {
     assertThrows(
         IllegalStateException.class,
         () -> emptyAccumulatorByAddAllEmptyStats.populationStandardDeviation());
-    assertThat(oneValueAccumulator.populationStandardDeviation()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationStandardDeviation())
-        .isWithin(0.0)
-        .of(0.0);
+    assertThat(oneValueAccumulator.populationStandardDeviation()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationStandardDeviation()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationStandardDeviation())
         .isWithin(ALLOWED_ERROR)
         .of(sqrt(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2));
diff --git a/android/guava-tests/test/com/google/common/math/StatsTest.java b/android/guava-tests/test/com/google/common/math/StatsTest.java
@@ -191,7 +191,7 @@ public void testSum() {
   public void testPopulationVariance() {
     assertThrows(IllegalStateException.class, () -> EMPTY_STATS_VARARGS.populationVariance());
     assertThrows(IllegalStateException.class, () -> EMPTY_STATS_ITERABLE.populationVariance());
-    assertThat(ONE_VALUE_STATS.populationVariance()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_STATS.populationVariance()).isEqualTo(0.0);
     assertThat(Stats.of(POSITIVE_INFINITY).populationVariance()).isNaN();
     assertThat(Stats.of(NEGATIVE_INFINITY).populationVariance()).isNaN();
     assertThat(Stats.of(NaN).populationVariance()).isNaN();
@@ -245,7 +245,7 @@ public void testPopulationStandardDeviation() {
         IllegalStateException.class, () -> EMPTY_STATS_VARARGS.populationStandardDeviation());
     assertThrows(
         IllegalStateException.class, () -> EMPTY_STATS_ITERABLE.populationStandardDeviation());
-    assertThat(ONE_VALUE_STATS.populationStandardDeviation()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_STATS.populationStandardDeviation()).isEqualTo(0.0);
     assertThat(TWO_VALUES_STATS.populationStandardDeviation())
         .isWithin(ALLOWED_ERROR)
         .of(sqrt(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2));
diff --git a/android/guava-tests/test/com/google/common/math/StatsTesting.java b/android/guava-tests/test/com/google/common/math/StatsTesting.java
@@ -354,7 +354,7 @@ static void assertStatsApproxEqual(Stats expectedStats, Stats actualStats) {
       }
     } else if (expectedStats.count() == 1) {
       assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());
-      assertThat(actualStats.populationVariance()).isWithin(0.0).of(0.0);
+      assertThat(actualStats.populationVariance()).isEqualTo(0.0);
       assertThat(actualStats.min()).isWithin(ALLOWED_ERROR).of(expectedStats.min());
       assertThat(actualStats.max()).isWithin(ALLOWED_ERROR).of(expectedStats.max());
     } else {
diff --git a/android/guava-tests/test/com/google/common/primitives/UnsignedLongTest.java b/android/guava-tests/test/com/google/common/primitives/UnsignedLongTest.java
@@ -151,8 +151,7 @@ public void testFloatValue() {
       UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);
       assertWithMessage("Float value of " + unsignedValue)
           .that(unsignedValue.floatValue())
-          .isWithin(0.0f)
-          .of(unsignedValue.bigIntegerValue().floatValue());
+          .isEqualTo(unsignedValue.bigIntegerValue().floatValue());
     }
   }
 
@@ -161,8 +160,7 @@ public void testDoubleValue() {
       UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);
       assertWithMessage("Double value of " + unsignedValue)
           .that(unsignedValue.doubleValue())
-          .isWithin(0.0)
-          .of(unsignedValue.bigIntegerValue().doubleValue());
+          .isEqualTo(unsignedValue.bigIntegerValue().doubleValue());
     }
   }
 
diff --git a/guava-tests/test/com/google/common/math/PairedStatsAccumulatorTest.java b/guava-tests/test/com/google/common/math/PairedStatsAccumulatorTest.java
@@ -179,10 +179,8 @@ public void testPopulationCovariance() {
     assertThrows(
         IllegalStateException.class,
         () -> emptyAccumulatorByAddAllEmptyPairedStats.populationCovariance());
-    assertThat(oneValueAccumulator.populationCovariance()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyPairedStats.populationCovariance())
-        .isWithin(0.0)
-        .of(0.0);
+    assertThat(oneValueAccumulator.populationCovariance()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyPairedStats.populationCovariance()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationCovariance())
         .isWithin(ALLOWED_ERROR)
         .of(TWO_VALUES_SUM_OF_PRODUCTS_OF_DELTAS / 2);
diff --git a/guava-tests/test/com/google/common/math/PairedStatsTest.java b/guava-tests/test/com/google/common/math/PairedStatsTest.java
@@ -89,7 +89,7 @@ public void testYStats() {
 
   public void testPopulationCovariance() {
     assertThrows(IllegalStateException.class, () -> EMPTY_PAIRED_STATS.populationCovariance());
-    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_PAIRED_STATS.populationCovariance()).isEqualTo(0.0);
     assertThat(createSingleStats(Double.POSITIVE_INFINITY, 1.23).populationCovariance()).isNaN();
     assertThat(createSingleStats(Double.NEGATIVE_INFINITY, 1.23).populationCovariance()).isNaN();
     assertThat(createSingleStats(Double.NaN, 1.23).populationCovariance()).isNaN();
diff --git a/guava-tests/test/com/google/common/math/StatsAccumulatorTest.java b/guava-tests/test/com/google/common/math/StatsAccumulatorTest.java
@@ -276,9 +276,9 @@ public void testMean() {
   }
 
   public void testSum() {
-    assertThat(emptyAccumulator.sum()).isWithin(0.0).of(0.0);
-    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isWithin(0.0).of(0.0);
-    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isWithin(0.0).of(0.0);
+    assertThat(emptyAccumulator.sum()).isEqualTo(0.0);
+    assertThat(emptyAccumulatorByAddAllEmptyIterable.sum()).isEqualTo(0.0);
+    assertThat(emptyAccumulatorByAddAllEmptyStats.sum()).isEqualTo(0.0);
     assertThat(oneValueAccumulator.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
     assertThat(oneValueAccumulatorByAddAllEmptyStats.sum()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
     assertThat(twoValuesAccumulator.sum()).isWithin(ALLOWED_ERROR).of(TWO_VALUES_MEAN * 2);
@@ -324,8 +324,8 @@ public void testPopulationVariance() {
         () -> emptyAccumulatorByAddAllEmptyIterable.populationVariance());
     assertThrows(
         IllegalStateException.class, () -> emptyAccumulatorByAddAllEmptyStats.populationVariance());
-    assertThat(oneValueAccumulator.populationVariance()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationVariance()).isWithin(0.0).of(0.0);
+    assertThat(oneValueAccumulator.populationVariance()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationVariance()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationVariance())
         .isWithin(ALLOWED_ERROR)
         .of(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2);
@@ -399,10 +399,8 @@ public void testPopulationStandardDeviation() {
     assertThrows(
         IllegalStateException.class,
         () -> emptyAccumulatorByAddAllEmptyStats.populationStandardDeviation());
-    assertThat(oneValueAccumulator.populationStandardDeviation()).isWithin(0.0).of(0.0);
-    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationStandardDeviation())
-        .isWithin(0.0)
-        .of(0.0);
+    assertThat(oneValueAccumulator.populationStandardDeviation()).isEqualTo(0.0);
+    assertThat(oneValueAccumulatorByAddAllEmptyStats.populationStandardDeviation()).isEqualTo(0.0);
     assertThat(twoValuesAccumulator.populationStandardDeviation())
         .isWithin(ALLOWED_ERROR)
         .of(sqrt(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2));
diff --git a/guava-tests/test/com/google/common/math/StatsTest.java b/guava-tests/test/com/google/common/math/StatsTest.java
@@ -199,7 +199,7 @@ public void testSum() {
   public void testPopulationVariance() {
     assertThrows(IllegalStateException.class, () -> EMPTY_STATS_VARARGS.populationVariance());
     assertThrows(IllegalStateException.class, () -> EMPTY_STATS_ITERABLE.populationVariance());
-    assertThat(ONE_VALUE_STATS.populationVariance()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_STATS.populationVariance()).isEqualTo(0.0);
     assertThat(Stats.of(POSITIVE_INFINITY).populationVariance()).isNaN();
     assertThat(Stats.of(NEGATIVE_INFINITY).populationVariance()).isNaN();
     assertThat(Stats.of(NaN).populationVariance()).isNaN();
@@ -253,7 +253,7 @@ public void testPopulationStandardDeviation() {
         IllegalStateException.class, () -> EMPTY_STATS_VARARGS.populationStandardDeviation());
     assertThrows(
         IllegalStateException.class, () -> EMPTY_STATS_ITERABLE.populationStandardDeviation());
-    assertThat(ONE_VALUE_STATS.populationStandardDeviation()).isWithin(0.0).of(0.0);
+    assertThat(ONE_VALUE_STATS.populationStandardDeviation()).isEqualTo(0.0);
     assertThat(TWO_VALUES_STATS.populationStandardDeviation())
         .isWithin(ALLOWED_ERROR)
         .of(sqrt(TWO_VALUES_SUM_OF_SQUARES_OF_DELTAS / 2));
diff --git a/guava-tests/test/com/google/common/math/StatsTesting.java b/guava-tests/test/com/google/common/math/StatsTesting.java
@@ -384,7 +384,7 @@ static void assertStatsApproxEqual(Stats expectedStats, Stats actualStats) {
       }
     } else if (expectedStats.count() == 1) {
       assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());
-      assertThat(actualStats.populationVariance()).isWithin(0.0).of(0.0);
+      assertThat(actualStats.populationVariance()).isEqualTo(0.0);
       assertThat(actualStats.min()).isWithin(ALLOWED_ERROR).of(expectedStats.min());
       assertThat(actualStats.max()).isWithin(ALLOWED_ERROR).of(expectedStats.max());
     } else {
diff --git a/guava-tests/test/com/google/common/primitives/UnsignedLongTest.java b/guava-tests/test/com/google/common/primitives/UnsignedLongTest.java
@@ -151,8 +151,7 @@ public void testFloatValue() {
       UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);
       assertWithMessage("Float value of " + unsignedValue)
           .that(unsignedValue.floatValue())
-          .isWithin(0.0f)
-          .of(unsignedValue.bigIntegerValue().floatValue());
+          .isEqualTo(unsignedValue.bigIntegerValue().floatValue());
     }
   }
 
@@ -161,8 +160,7 @@ public void testDoubleValue() {
       UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);
       assertWithMessage("Double value of " + unsignedValue)
           .that(unsignedValue.doubleValue())
-          .isWithin(0.0)
-          .of(unsignedValue.bigIntegerValue().doubleValue());
+          .isEqualTo(unsignedValue.bigIntegerValue().doubleValue());
     }
   }
 

Original file line number	Diff line number	Diff line change
`@@ -354,7 +354,7 @@ static void assertStatsApproxEqual(Stats expectedStats, Stats actualStats) {`
`354`	`354`	`}`
`355`	`355`	`} else if (expectedStats.count() == 1) {`
`356`	`356`	`assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());`
`357`		`- assertThat(actualStats.populationVariance()).isWithin(0.0).of(0.0);`
	`357`	`+ assertThat(actualStats.populationVariance()).isEqualTo(0.0);`
`358`	`358`	`assertThat(actualStats.min()).isWithin(ALLOWED_ERROR).of(expectedStats.min());`
`359`	`359`	`assertThat(actualStats.max()).isWithin(ALLOWED_ERROR).of(expectedStats.max());`
`360`	`360`	`} else {`
Original file line number	Diff line number	Diff line change
`@@ -151,8 +151,7 @@ public void testFloatValue() {`
`151`	`151`	`UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);`
`152`	`152`	`assertWithMessage("Float value of " + unsignedValue)`
`153`	`153`	`.that(unsignedValue.floatValue())`
`154`		`- .isWithin(0.0f)`
`155`		`- .of(unsignedValue.bigIntegerValue().floatValue());`
	`154`	`+ .isEqualTo(unsignedValue.bigIntegerValue().floatValue());`
`156`	`155`	`}`
`157`	`156`	`}`
`158`	`157`
`@@ -161,8 +160,7 @@ public void testDoubleValue() {`
`161`	`160`	`UnsignedLong unsignedValue = UnsignedLong.fromLongBits(value);`
`162`	`161`	`assertWithMessage("Double value of " + unsignedValue)`
`163`	`162`	`.that(unsignedValue.doubleValue())`
`164`		`- .isWithin(0.0)`
`165`		`- .of(unsignedValue.bigIntegerValue().doubleValue());`
	`163`	`+ .isEqualTo(unsignedValue.bigIntegerValue().doubleValue());`
`166`	`164`	`}`
`167`	`165`	`}`
`168`	`166`
Original file line number	Diff line number	Diff line change
`@@ -384,7 +384,7 @@ static void assertStatsApproxEqual(Stats expectedStats, Stats actualStats) {`
`384`	`384`	`}`
`385`	`385`	`} else if (expectedStats.count() == 1) {`
`386`	`386`	`assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());`
`387`		`- assertThat(actualStats.populationVariance()).isWithin(0.0).of(0.0);`
	`387`	`+ assertThat(actualStats.populationVariance()).isEqualTo(0.0);`
`388`	`388`	`assertThat(actualStats.min()).isWithin(ALLOWED_ERROR).of(expectedStats.min());`
`389`	`389`	`assertThat(actualStats.max()).isWithin(ALLOWED_ERROR).of(expectedStats.max());`
`390`	`390`	`} else {`