refactor: add convenience-method for validation

Also, maintain random-constructor flag when creating a new context for
specific field.

Author: Nylle

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

@@ -5,6 +5,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public class CustomizationContext {
     private final List<String> ignoredFields;
@@ -39,6 +40,10 @@ public boolean useRandomConstructor() {
         return useRandomConstructor;
     }
 
+    public Stream<String> findAllCustomizedFieldNames() {
+        return Stream.concat(customFields.keySet().stream(), ignoredFields.stream());
+    }
+
     public CustomizationContext newForField(String name) {
         return new CustomizationContext(
                 ignoredFields.stream()
@@ -49,6 +54,6 @@ public CustomizationContext newForField(String name) {
                         .filter(x -> x.getKey().startsWith(name + "."))
                         .map(x -> Map.entry(x.getKey().substring(name.length() + 1), x.getValue()))
                         .collect(Collectors.toMap(k -> k.getKey(), v -> v.getValue())),
-                false);
+                useRandomConstructor);
     }
 }

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

@@ -28,7 +28,7 @@ public Reflector(T instance, SpecimenType<T> type) {
     public Reflector<T> validateCustomization(CustomizationContext customizationContext) {
         var declaredFields = getDeclaredFields(type.asClass()).map(field -> field.getName()).collect(toList());
 
-        var missingDeclaredField = Stream.concat(customizationContext.getCustomFields().keySet().stream(), customizationContext.getIgnoredFields().stream())
+        var missingDeclaredField = customizationContext.findAllCustomizedFieldNames()
                 .map(entry -> entry.replaceAll("\\..+", ""))
                 .filter(entry -> !declaredFields.contains(entry))
                 .findFirst();
@@ -42,7 +42,7 @@ public Reflector<T> validateCustomization(CustomizationContext customizationCont
                 .entrySet()
                 .stream()
                 .filter(x -> x.getValue().size() > 1)
-                .filter(x -> Stream.concat(customizationContext.getCustomFields().keySet().stream(), customizationContext.getIgnoredFields().stream())
+                .filter(x -> customizationContext.findAllCustomizedFieldNames()
                         .map(entry -> entry.replaceAll("\\..+", ""))
                         .anyMatch(y -> y.equals(x.getKey())))
                 .findFirst();

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

@@ -8,6 +8,7 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -67,12 +68,21 @@ void returnsContextWithEmptyCustomizedNestedFieldWhenFieldHasNoNestedFields(Obje
         @TestWithCases
         @TestCase(bool1 = true)
         @TestCase(bool1 = false)
-        void useRandomConstructorIsAlwaysFalse(boolean useRandomConstructor, @com.github.nylle.javafixture.annotations.testcases.Fixture String fieldName) {
+        void useRandomConstructorIsMaintained(boolean useRandomConstructor, @com.github.nylle.javafixture.annotations.testcases.Fixture String fieldName) {
             var sut = new CustomizationContext(List.of(), Map.of(), useRandomConstructor);
 
             var actual = sut.newForField(fieldName);
 
-            assertThat(actual.useRandomConstructor()).isFalse();
+            assertThat(actual.useRandomConstructor()).isEqualTo(useRandomConstructor);
         }
     }
+
+    @Test
+    void findAllCustomizedFieldNames() {
+        var sut = new CustomizationContext(List.of("remove"), Map.of("change", new Object()), false);
+
+        var actual = sut.findAllCustomizedFieldNames().collect(Collectors.toList());
+
+        assertThat(actual).containsExactlyInAnyOrder("remove", "change");
+    }
 }