Fix equalsAndHashCode generation (#12)

Author: kobylynskyi

src/main/resources/templates/javaClassGraphqlType.ftl

@@ -41,20 +41,21 @@ public class ${className} <#if implements?has_content>implements <#list implemen
         if (this == obj) {
             return true;
         }
-        if (that == null || getClass() != obj.getClass()) {
+        if (obj == null || getClass() != obj.getClass()) {
             return false;
         }
-        final ${className} that = (FormField) obj;
-        return <#list fields as field>Objects.equals(${field.name}, that.${field.name}) <#if field_has_next>
+        final ${className} that = (${className}) obj;
+        return <#list fields as field>Objects.equals(${field.name}, that.${field.name})<#if field_has_next>
             && </#if></#list>;
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(
-<#list fields as field>
-            ${field.name}<#if field_has_next>, </#if>
-</#list>;
+<#if fields?has_content>
+        return Objects.hash(<#list fields as field>${field.name}<#if field_has_next>, </#if></#list>);
+<#else>
+        return 0;
+</#if>
     }
 </#if>
 }

src/test/java/com/kobylynskyi/graphql/codegen/GraphqlCodegenTest.java

@@ -217,7 +217,6 @@ void generate_EqualsAndHashCode() throws Exception {
         mappingConfig.setGenerateEqualsAndHashCode(true);
         mappingConfig.setModelNameSuffix("TO");
 
-
         generator.generate();
 
         File[] files = Objects.requireNonNull(outputJavaClassesDir.listFiles());
@@ -239,7 +238,10 @@ void generate_EqualsAndHashCode() throws Exception {
             }
         }
 
-
+        assertEquals(Utils.getFileContent("src/test/resources/expected-classes/EventPropertyTO_withEqualsAndHashCode.java.txt"),
+                Utils.getFileContent(Arrays.stream(files)
+                        .filter(f -> f.getName().equals("EventPropertyTO.java"))
+                        .map(File::getPath).findFirst().orElseThrow(FileNotFoundException::new)));
     }
 
     @Test

src/test/resources/expected-classes/EventPropertyTO_withEqualsAndHashCode.java.txt

@@ -0,0 +1,89 @@
+package com.kobylynskyi.graphql.test1;
+
+import java.util.*;
+
+public class EventPropertyTO {
+
+    private Float floatVal;
+    private Boolean booleanVal;
+    private Integer intVal;
+    private String stringVal;
+    private Collection<EventPropertyTO> child;
+    private EventTO parent;
+
+    public EventPropertyTO() {
+    }
+
+    public EventPropertyTO(Float floatVal, Boolean booleanVal, Integer intVal, String stringVal, Collection<EventPropertyTO> child, EventTO parent) {
+        this.floatVal = floatVal;
+        this.booleanVal = booleanVal;
+        this.intVal = intVal;
+        this.stringVal = stringVal;
+        this.child = child;
+        this.parent = parent;
+    }
+
+    public Float getFloatVal() {
+        return floatVal;
+    }
+    public void setFloatVal(Float floatVal) {
+        this.floatVal = floatVal;
+    }
+
+    public Boolean getBooleanVal() {
+        return booleanVal;
+    }
+    public void setBooleanVal(Boolean booleanVal) {
+        this.booleanVal = booleanVal;
+    }
+
+    public Integer getIntVal() {
+        return intVal;
+    }
+    public void setIntVal(Integer intVal) {
+        this.intVal = intVal;
+    }
+
+    public String getStringVal() {
+        return stringVal;
+    }
+    public void setStringVal(String stringVal) {
+        this.stringVal = stringVal;
+    }
+
+    public Collection<EventPropertyTO> getChild() {
+        return child;
+    }
+    public void setChild(Collection<EventPropertyTO> child) {
+        this.child = child;
+    }
+
+    public EventTO getParent() {
+        return parent;
+    }
+    public void setParent(EventTO parent) {
+        this.parent = parent;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null || getClass() != obj.getClass()) {
+            return false;
+        }
+        final EventPropertyTO that = (EventPropertyTO) obj;
+        return Objects.equals(floatVal, that.floatVal)
+            && Objects.equals(booleanVal, that.booleanVal)
+            && Objects.equals(intVal, that.intVal)
+            && Objects.equals(stringVal, that.stringVal)
+            && Objects.equals(child, that.child)
+            && Objects.equals(parent, that.parent);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(floatVal, booleanVal, intVal, stringVal, child, parent);
+    }
+}