feat: Use constructor when reflection fails

Refs: JF-63

Author: akutschera

src/main/java/com/github/nylle/javafixture/Context.java

@@ -35,6 +35,11 @@ public boolean isCached(SpecimenType<?> type) {
         return cache.containsKey(type.hashCode());
     }
 
+    public <T> T overwrite(SpecimenType<?> type, T instance) {
+        cache.put(type.hashCode(), instance);
+        return (T) cache.get(type.hashCode());
+    }
+
     public <T> T cached(SpecimenType<?> type, T instance) {
         cache.putIfAbsent(type.hashCode(), instance);
         return (T) cache.get(type.hashCode());

src/main/java/com/github/nylle/javafixture/specimen/GenericSpecimen.java

@@ -9,6 +9,7 @@
 import com.github.nylle.javafixture.SpecimenType;
 
 import java.lang.annotation.Annotation;
+import java.lang.reflect.InaccessibleObjectException;
 import java.util.Map;
 import java.util.stream.IntStream;
 
@@ -87,14 +88,18 @@ private T populate(CustomizationContext customizationContext) {
         var result = context.cached(type, instanceFactory.instantiate(type));
         var reflector = new Reflector<>(result)
                 .validateCustomization(customizationContext, type);
-        reflector.getDeclaredFields()
-                .filter(field -> !customizationContext.getIgnoredFields().contains(field.getName()))
-                .forEach(field -> reflector.setField(field,
-                        customizationContext.getCustomFields().getOrDefault(
-                                field.getName(),
-                                specimens.getOrDefault(
-                                        field.getGenericType().getTypeName(),
-                                        specimenFactory.build(SpecimenType.fromClass(field.getType()))).create(new Annotation[0]))));
+        try {
+            reflector.getDeclaredFields()
+                    .filter(field -> !customizationContext.getIgnoredFields().contains(field.getName()))
+                    .forEach(field -> reflector.setField(field,
+                            customizationContext.getCustomFields().getOrDefault(
+                                    field.getName(),
+                                    specimens.getOrDefault(
+                                            field.getGenericType().getTypeName(),
+                                            specimenFactory.build(SpecimenType.fromClass(field.getType()))).create(new Annotation[0]))));
+        } catch (InaccessibleObjectException ex ) {
+            return context.overwrite(type, instanceFactory.construct(type));
+        }
         return result;
     }
 }

src/main/java/com/github/nylle/javafixture/specimen/ObjectSpecimen.java

@@ -9,6 +9,7 @@
 import com.github.nylle.javafixture.SpecimenType;
 
 import java.lang.annotation.Annotation;
+import java.lang.reflect.InaccessibleObjectException;
 import java.util.Map;
 
 import static com.github.nylle.javafixture.CustomizationContext.noContext;
@@ -66,14 +67,18 @@ private T populate(CustomizationContext customizationContext) {
         var result = context.cached(type, instanceFactory.instantiate(type));
         var reflector = new Reflector<>(result)
                 .validateCustomization(customizationContext, type);
-        reflector.getDeclaredFields()
-                .filter(field -> !customizationContext.getIgnoredFields().contains(field.getName()))
-                .forEach(field -> reflector.setField(field,
-                        customizationContext.getCustomFields().getOrDefault(
-                                field.getName(),
-                                Map.<String, ISpecimen<?>>of().getOrDefault(
-                                        field.getGenericType().getTypeName(),
-                                        specimenFactory.build(SpecimenType.fromClass(field.getGenericType()))).create(field.getAnnotations()))));
+        try {
+            reflector.getDeclaredFields()
+                    .filter(field -> !customizationContext.getIgnoredFields().contains(field.getName()))
+                    .forEach(field -> reflector.setField(field,
+                            customizationContext.getCustomFields().getOrDefault(
+                                    field.getName(),
+                                    Map.<String, ISpecimen<?>>of().getOrDefault(
+                                            field.getGenericType().getTypeName(),
+                                            specimenFactory.build(SpecimenType.fromClass(field.getGenericType()))).create(field.getAnnotations()))));
+        } catch (InaccessibleObjectException ex ) {
+            return context.overwrite(type, instanceFactory.construct(type));
+        }
         return result;
     }
 }

src/test/java/com/github/nylle/javafixture/ContextTest.java

@@ -41,6 +41,21 @@ void cachedReturnsCachedInstanceWhenExisting() {
 
     }
 
+    @Test
+    void overwriteWillRemovePreviousValue() {
+        var sut = new Context(new Configuration());
+
+        var unexpected = new TestObject("Hello!");
+        sut.cached(SpecimenType.fromClass(Integer.class), unexpected);
+
+        var expected = new TestObject("World!");
+        var actual = sut.overwrite(SpecimenType.fromClass(Integer.class), expected);
+
+        assertThat(actual).isEqualTo(expected);
+        assertThat(actual.getValue()).isEqualTo("World!");
+
+    }
+
     class TestObject {
         private final String value;
 

src/test/java/com/github/nylle/javafixture/FixtureTest.java

@@ -19,7 +19,6 @@
 import com.github.nylle.javafixture.testobjects.example.Contract;
 import com.github.nylle.javafixture.testobjects.example.ContractCategory;
 import com.github.nylle.javafixture.testobjects.example.ContractPosition;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
@@ -295,19 +294,6 @@ void canCreateComplexModel() {
             assertThat(firstContractPosition.getFile()).isInstanceOf(File.class);
         }
 
-        @Test
-        void canCreateThrowable() {
-            Fixture fixture = new Fixture(configuration);
-
-            Throwable result = fixture.create(Throwable.class);
-            assertThat(result).isInstanceOf(Throwable.class);
-            assertThat(result.getMessage().length()).isGreaterThan(0);
-            assertThat(result.getLocalizedMessage().length()).isGreaterThan(0);
-            assertThat(result.getStackTrace().length).isGreaterThan(0);
-            assertThat(result.getStackTrace()[0]).isInstanceOf(StackTraceElement.class);
-            assertThat(result.getCause()).isNull(); //if cause == this, the getter returns null
-        }
-
         @Test
         void canCreateNestedParameterizedCollections() {
             Fixture fixture = new Fixture(configuration);
@@ -596,7 +582,6 @@ void createThroughRandomConstructor() {
     }
 
     @Test
-    @Disabled("This is a known problem")
     void createExceptionWithLimitedTree() {
 
         var sut = new Fixture(configuration);

src/test/java/com/github/nylle/javafixture/specimen/ObjectSpecimenTest.java

@@ -86,7 +86,6 @@ void create() {
         assertThat(second.getKey()).isExactlyInstanceOf(Integer.class);
         assertThat(second.getValue()).isExactlyInstanceOf(String.class);
     }
-
     @Test
     void resultIsCached() {
 
@@ -98,6 +97,13 @@ void resultIsCached() {
         assertThat(original.getValue()).isEqualTo(cached.getValue());
         assertThat(original.getIntegers()).isEqualTo(cached.getIntegers());
     }
+    @Test
+    void revertToConstructorIfReflectionFails() {
+
+        var actual = new ObjectSpecimen<Throwable>(new SpecimenType<>(){}, context, specimenFactory).create(new Annotation[0]);
+
+        assertThat(actual).isInstanceOf(Throwable.class);
+    }
 
     @Test
     void ignoresStaticFields() {