Fix expression equality (#1003)

Author: nakamura-to

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/expression/AggregateFunction.java

@@ -43,7 +43,7 @@ public PropertyMetamodel<?> argument() {
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof AbstractFunction)) return false;
+      if (o == null || getClass() != o.getClass()) return false;
       AbstractFunction<?> that = (AbstractFunction<?>) o;
       return name.equals(that.name) && argument.equals(that.argument);
     }
@@ -124,6 +124,20 @@ public void accept(PropertyMetamodel.Visitor visitor) {
         v.visit(this);
       }
     }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) return true;
+      if (o == null || getClass() != o.getClass()) return false;
+      if (!super.equals(o)) return false;
+      Count count = (Count) o;
+      return distinct == count.distinct;
+    }
+
+    @Override
+    public int hashCode() {
+      return Objects.hash(super.hashCode(), distinct);
+    }
   }
 
   class Max<PROPERTY> extends AbstractFunction<PROPERTY> {

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/expression/ArithmeticExpression.java

@@ -32,7 +32,7 @@ public Class<?> asClass() {
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof AbstractArithmeticExpression)) return false;
+      if (o == null || getClass() != o.getClass()) return false;
       AbstractArithmeticExpression<?> that = (AbstractArithmeticExpression<?>) o;
       return propertyMetamodel.equals(that.propertyMetamodel)
           && left.equals(that.left)

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/expression/StringExpression.java

@@ -34,7 +34,7 @@ public Class<?> asClass() {
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof StringExpression.OneArgumentStringExpression)) return false;
+      if (o == null || getClass() != o.getClass()) return false;
       OneArgumentStringExpression<?> that = (OneArgumentStringExpression<?>) o;
       return argument.equals(that.argument);
     }
@@ -80,7 +80,7 @@ public Class<?> asClass() {
     @Override
     public boolean equals(Object o) {
       if (this == o) return true;
-      if (!(o instanceof StringExpression.TwoArgumentsStringExpression)) return false;
+      if (o == null || getClass() != o.getClass()) return false;
       TwoArgumentsStringExpression<?> that = (TwoArgumentsStringExpression<?>) o;
       return propertyMetamodel.equals(that.propertyMetamodel)
           && first.equals(that.first)

doma-core/src/test/java/org/seasar/doma/jdbc/criteria/expression/ExpressionsTest.java

@@ -25,6 +25,7 @@
 import org.junit.jupiter.api.Test;
 import org.seasar.doma.DomaIllegalArgumentException;
 import org.seasar.doma.jdbc.criteria.entity.Emp_;
+import org.seasar.doma.jdbc.criteria.metamodel.PropertyMetamodel;
 
 class ExpressionsTest {
 
@@ -229,4 +230,41 @@ void testSum() {
     assertEquals("sum", sum(e.id).getName());
     assertEquals(e.id, sum(e.id).argument());
   }
+
+  @Test
+  void testEquality() {
+    PropertyMetamodel<?> sum = sum(e.id);
+    PropertyMetamodel<?> div = div(sum(e.id), 1);
+    PropertyMetamodel<?> mod = mod(sum(e.id), 1);
+    PropertyMetamodel<?> mul = mul(sum(e.id), 1);
+    PropertyMetamodel<?> sub = sub(sum(e.id), 1);
+    PropertyMetamodel<?> add = add(sum(e.id), 1);
+
+    assertEquals(sum, sum(e.id));
+    assertEquals(div, div(sum(e.id), 1));
+    assertEquals(mod, mod(sum(e.id), 1));
+    assertEquals(mul, mul(sum(e.id), 1));
+    assertEquals(sub, sub(sum(e.id), 1));
+    assertEquals(add, add(sum(e.id), 1));
+
+    assertNotEquals(sum, div);
+    assertNotEquals(sum, mod);
+    assertNotEquals(sum, mul);
+    assertNotEquals(sum, sub);
+    assertNotEquals(sum, add);
+
+    assertNotEquals(div, mod);
+    assertNotEquals(div, mul);
+    assertNotEquals(div, sub);
+    assertNotEquals(div, add);
+
+    assertNotEquals(mod, mul);
+    assertNotEquals(mod, sub);
+    assertNotEquals(mod, add);
+
+    assertNotEquals(mul, sub);
+    assertNotEquals(mul, add);
+
+    assertNotEquals(sub, add);
+  }
 }