fix: No change if same minItems or maxItems (#780)

* fix: No change if same minItems or maxItems

* feat: Test adding or removing property

Author: danilofuchs

core/src/main/java/org/openapitools/openapidiff/core/model/schema/ChangedMaxItems.java

@@ -17,7 +17,7 @@ public ChangedMaxItems(Integer oldValue, Integer newValue, DiffContext context)
 
   @Override
   public DiffResult isChanged() {
-    if (oldValue == null && newValue == null) {
+    if (oldValue == newValue) {
       return DiffResult.NO_CHANGES;
     }
     if (oldValue == null || newValue == null) {

core/src/main/java/org/openapitools/openapidiff/core/model/schema/ChangedMinItems.java

@@ -17,7 +17,7 @@ public ChangedMinItems(Integer oldValue, Integer newValue, DiffContext context)
 
   @Override
   public DiffResult isChanged() {
-    if (oldValue == null && newValue == null) {
+    if (oldValue == newValue) {
       return DiffResult.NO_CHANGES;
     }
     if (oldValue == null || newValue == null) {

core/src/test/java/org/openapitools/openapidiff/core/SchemaDiffTest.java

@@ -144,7 +144,7 @@ public void changeMultipleOfHandling() {
     assertThat(props.get("field4").getMultipleOf().getRight()).isNull();
   }
 
-  @Test // issues #480
+  @Test // issues #480 and #779
   public void changeMinMaxItemsHandling() {
     ChangedOpenApi changedOpenApi =
         OpenApiCompare.fromLocations(
@@ -158,6 +158,9 @@ public void changeMinMaxItemsHandling() {
     Map<String, ChangedSchema> props = changedSchema.getChangedProperties();
     assertThat(props).isNotEmpty();
 
+    // Check no changes in minItems and maxItems
+    assertThat(props.get("field0")).isNull();
+
     // Check increasing of minItems
     assertThat(props.get("field1").getMinItems().isIncompatible()).isTrue();
     assertThat(props.get("field1").getMinItems().getOldValue()).isEqualTo(1);
@@ -177,6 +180,26 @@ public void changeMinMaxItemsHandling() {
     assertThat(props.get("field4").getMaxItems().isIncompatible()).isTrue();
     assertThat(props.get("field4").getMaxItems().getOldValue()).isEqualTo(100);
     assertThat(props.get("field4").getMaxItems().getNewValue()).isEqualTo(90);
+
+    // Check removal of minItems
+    assertThat(props.get("field5").getMinItems().isCompatible()).isTrue();
+    assertThat(props.get("field5").getMinItems().getOldValue()).isEqualTo(1);
+    assertThat(props.get("field5").getMinItems().getNewValue()).isNull();
+
+    // Check removal of maxItems
+    assertThat(props.get("field5").getMaxItems().isCompatible()).isTrue();
+    assertThat(props.get("field5").getMaxItems().getOldValue()).isEqualTo(100);
+    assertThat(props.get("field5").getMaxItems().getNewValue()).isNull();
+
+    // Check addition of minItems
+    assertThat(props.get("field6").getMinItems().isCompatible()).isTrue();
+    assertThat(props.get("field6").getMinItems().getOldValue()).isNull();
+    assertThat(props.get("field6").getMinItems().getNewValue()).isEqualTo(1);
+
+    // Check addition of maxItems
+    assertThat(props.get("field6").getMaxItems().isCompatible()).isTrue();
+    assertThat(props.get("field6").getMaxItems().getOldValue()).isNull();
+    assertThat(props.get("field6").getMaxItems().getNewValue()).isEqualTo(100);
   }
 
   @Test // issue #482

core/src/test/resources/schemaDiff/schema-min-max-items-diff-1.yaml

@@ -16,6 +16,12 @@ components:
     TestDTO:
       type: object
       properties:
+        field0:
+          type: array
+          items:
+            type: string
+          minItems: 1
+          maxItems: 10
         field1:
           type: array
           items:
@@ -33,10 +39,20 @@ components:
           items:
             type: string
           minItems: 1
-          maxItems: 90              
+          maxItems: 90
         field4:
           type: array
           items:
             type: string
           minItems: 1
           maxItems: 100
+        field5:
+          type: array
+          items:
+            type: string
+          minItems: 1
+          maxItems: 100
+        field6:
+          type: array
+          items:
+            type: string

core/src/test/resources/schemaDiff/schema-min-max-items-diff-2.yaml

@@ -16,6 +16,12 @@ components:
     TestDTO:
       type: object
       properties:
+        field0:
+          type: array
+          items:
+            type: string
+          minItems: 1
+          maxItems: 10
         field1:
           type: array
           items:
@@ -27,16 +33,26 @@ components:
           items:
             type: string
           minItems: 10
-          maxItems: 100  
+          maxItems: 100
         field3:
           type: array
           items:
             type: string
           minItems: 1
-          maxItems: 100  
+          maxItems: 100
         field4:
           type: array
           items:
             type: string
           minItems: 1
           maxItems: 90
+        field5:
+          type: array
+          items:
+            type: string
+        field6:
+          type: array
+          items:
+            type: string
+          minItems: 1
+          maxItems: 100