Let ValueProvider return an Optional

jqno · Dec 4, 2024 · 411284c · 411284c
1 parent d1c00ba
commit 411284c
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Showing 12 changed files with 100 additions and 28 deletions.
diff --git a/...ore/src/main/java/nl/jqno/equalsverifier/internal/checkers/AbstractDelegationChecker.java b/...ore/src/main/java/nl/jqno/equalsverifier/internal/checkers/AbstractDelegationChecker.java
@@ -74,7 +74,7 @@ private void checkAbstractDelegationInFields() {
 
     private <U> Tuple<U> safelyGetTuple(TypeTag tag) {
         try {
-            return valueProvider.provide(tag);
+            return valueProvider.provideOrThrow(tag);
         } catch (Exception ignored) {
             // If it fails for some reason, any reason, just return null so we can skip the test.
             return null;

diff --git a/...ain/java/nl/jqno/equalsverifier/internal/checkers/MapEntryHashCodeRequirementChecker.java b/...ain/java/nl/jqno/equalsverifier/internal/checkers/MapEntryHashCodeRequirementChecker.java
@@ -23,7 +23,7 @@ public MapEntryHashCodeRequirementChecker(Context<T> context) {
     public void check() {
         if (Map.Entry.class.isAssignableFrom(config.getType())) {
             Map.Entry<?, ?> e = valueProvider
-                .<Map.Entry<?, ?>>provide(config.getTypeTag())
+                .<Map.Entry<?, ?>>provideOrThrow(config.getTypeTag())
                 .getRed();
 
             int expectedHashCode = Objects.hashCode(e.getKey()) ^ Objects.hashCode(e.getValue());

diff --git a/...in/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/JpaLazyGetterFieldCheck.java b/...in/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/JpaLazyGetterFieldCheck.java
@@ -9,11 +9,7 @@
 import java.util.function.Function;
 import nl.jqno.equalsverifier.Warning;
 import nl.jqno.equalsverifier.internal.exceptions.EqualsVerifierInternalBugException;
-import nl.jqno.equalsverifier.internal.reflection.ClassProbe;
-import nl.jqno.equalsverifier.internal.reflection.FieldProbe;
-import nl.jqno.equalsverifier.internal.reflection.Instantiator;
-import nl.jqno.equalsverifier.internal.reflection.Tuple;
-import nl.jqno.equalsverifier.internal.reflection.TypeTag;
+import nl.jqno.equalsverifier.internal.reflection.*;
 import nl.jqno.equalsverifier.internal.reflection.annotations.AnnotationCache;
 import nl.jqno.equalsverifier.internal.reflection.annotations.SupportedAnnotations;
 import nl.jqno.equalsverifier.internal.reflection.instantiation.SubjectCreator;
@@ -67,8 +63,8 @@ public void execute(FieldProbe fieldProbe) {
             classProbe.hasMethod(getterName)
         );
 
-        Class<T> sub = throwingGetterCreator(getterName);
-        Tuple<T> tuple = valueProvider.<T>provide(new TypeTag(sub));
+        TypeTag sub = new TypeTag(throwingGetterCreator(getterName));
+        Tuple<T> tuple = valueProvider.<T>provideOrThrow(sub);
         T red1 = tuple.getRed();
         T red2 = tuple.getRedCopy();
 

diff --git a/...main/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/ReflexivityFieldCheck.java b/...main/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/ReflexivityFieldCheck.java
@@ -82,7 +82,7 @@ private void checkValueReflexivity(FieldProbe probe) {
         TypeTag tag = TypeTag.of(field, typeTag);
         Tuple<?> tuple = prefabbedFields.contains(fieldName)
             ? fieldCache.get(fieldName)
-            : valueProvider.provide(tag);
+            : valueProvider.provideOrThrow(tag);
 
         Object left = subjectCreator.withFieldSetTo(field, tuple.getRed());
         Object right = subjectCreator.withFieldSetTo(field, tuple.getRedCopy());

diff --git a/.../src/main/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/StringFieldCheck.java b/.../src/main/java/nl/jqno/equalsverifier/internal/checkers/fieldchecks/StringFieldCheck.java
@@ -40,7 +40,8 @@ public StringFieldCheck(
     )
     public void execute(FieldProbe fieldProbe) {
         if (String.class.equals(fieldProbe.getType()) && !fieldProbe.isStatic()) {
-            String red = valueProvider.<String>provide(new TypeTag(String.class)).getRed();
+            TypeTag string = new TypeTag(String.class);
+            String red = valueProvider.<String>provideOrThrow(string).getRed();
 
             final T reference;
             final T copy;

diff --git a/...ifier-core/src/main/java/nl/jqno/equalsverifier/internal/exceptions/NoValueException.java b/...ifier-core/src/main/java/nl/jqno/equalsverifier/internal/exceptions/NoValueException.java
@@ -0,0 +1,20 @@
+package nl.jqno.equalsverifier.internal.exceptions;
+
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import nl.jqno.equalsverifier.internal.reflection.TypeTag;
+
+@SuppressFBWarnings(value = "SE_BAD_FIELD", justification = "EqualsVerifier doesn't serialize.")
+public class NoValueException extends MessagingException {
+
+    private final TypeTag tag;
+
+    public NoValueException(TypeTag tag) {
+        super();
+        this.tag = tag;
+    }
+
+    @Override
+    public String getDescription() {
+        return "Could not find a value for " + tag + ". Please add prefab values for this type.";
+    }
+}
diff --git a/...rc/main/java/nl/jqno/equalsverifier/internal/reflection/instantiation/SubjectCreator.java b/...rc/main/java/nl/jqno/equalsverifier/internal/reflection/instantiation/SubjectCreator.java
@@ -244,7 +244,8 @@ private Tuple<?> valuesFor(Field f) {
             return fieldCache.get(fieldName);
         }
         try {
-            Tuple<?> tuple = valueProvider.provide(TypeTag.of(f, typeTag));
+            TypeTag fieldTag = TypeTag.of(f, typeTag);
+            Tuple<?> tuple = valueProvider.provideOrThrow(fieldTag);
             fieldCache.put(fieldName, tuple);
             return tuple;
         } catch (ModuleException e) {

diff --git a/...src/main/java/nl/jqno/equalsverifier/internal/reflection/instantiation/ValueProvider.java b/...src/main/java/nl/jqno/equalsverifier/internal/reflection/instantiation/ValueProvider.java
@@ -1,5 +1,7 @@
 package nl.jqno.equalsverifier.internal.reflection.instantiation;
 
+import java.util.Optional;
+import nl.jqno.equalsverifier.internal.exceptions.NoValueException;
 import nl.jqno.equalsverifier.internal.reflection.Tuple;
 import nl.jqno.equalsverifier.internal.reflection.TypeTag;
 
@@ -18,7 +20,22 @@ public interface ValueProvider {
      *
      * @param <T> The returned tuple will have this generic type.
      * @param tag A description of the desired type, including generic parameters.
-     * @return A tuple of two different values of the given type.
+     * @return A tuple of two different values of the given type, or an empty Optional if none
+     *      could be found.
      */
-    <T> Tuple<T> provide(TypeTag tag);
+    <T> Optional<Tuple<T>> provide(TypeTag tag);
+
+    /**
+     * Returns a tuple of prefabricated values of the specified type, or, if none exists, throws a
+     * NoValueException.
+     *
+     * @param <T> The returned tuple will have this generic type.
+     * @param tag A description of the desired type, including generic parameters.
+     * @return A tuple of two different values of the given type, or an empty Optional if none
+     *      could be found.
+     * @throws NoValueException if no value could be found for the given tag.
+     */
+    default <T> Tuple<T> provideOrThrow(TypeTag tag) {
+        return this.<T>provide(tag).orElseThrow(() -> new NoValueException(tag));
+    }
 }
diff --git a/...n/java/nl/jqno/equalsverifier/internal/reflection/instantiation/VintageValueProvider.java b/...n/java/nl/jqno/equalsverifier/internal/reflection/instantiation/VintageValueProvider.java
@@ -42,8 +42,8 @@ public VintageValueProvider(FactoryCache factoryCache, Objenesis objenesis) {
 
     /** {@inheritDoc} */
     @Override
-    public <T> Tuple<T> provide(TypeTag tag) {
-        return Rethrow.rethrow(() -> giveTuple(tag));
+    public <T> Optional<Tuple<T>> provide(TypeTag tag) {
+        return Rethrow.rethrow(() -> Optional.of(giveTuple(tag)));
     }
 
     /**

diff --git a/...r-core/src/test/java/nl/jqno/equalsverifier/internal/exceptions/NoValueExceptionTest.java b/...r-core/src/test/java/nl/jqno/equalsverifier/internal/exceptions/NoValueExceptionTest.java
@@ -0,0 +1,16 @@
+package nl.jqno.equalsverifier.internal.exceptions;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import nl.jqno.equalsverifier.internal.reflection.TypeTag;
+import org.junit.jupiter.api.Test;
+
+public class NoValueExceptionTest {
+
+    @Test
+    public void description() {
+        TypeTag tag = new TypeTag(String.class);
+        NoValueException e = new NoValueException(tag);
+        assertTrue(e.getDescription().contains("String"));
+    }
+}
diff --git a/...est/java/nl/jqno/equalsverifier/internal/reflection/instantiation/SubjectCreatorTest.java b/...est/java/nl/jqno/equalsverifier/internal/reflection/instantiation/SubjectCreatorTest.java
@@ -5,9 +5,12 @@
 
 import java.lang.reflect.Field;
 import java.util.Objects;
+import java.util.Optional;
+import nl.jqno.equalsverifier.internal.exceptions.NoValueException;
 import nl.jqno.equalsverifier.internal.reflection.FieldCache;
 import nl.jqno.equalsverifier.internal.reflection.Tuple;
 import nl.jqno.equalsverifier.internal.reflection.TypeTag;
+import nl.jqno.equalsverifier.internal.testhelpers.ExpectedException;
 import nl.jqno.equalsverifier.internal.util.Configuration;
 import nl.jqno.equalsverifier.internal.util.ConfigurationHelper;
 import org.junit.jupiter.api.BeforeEach;
@@ -49,9 +52,6 @@ public void setup() throws NoSuchFieldException {
         fieldS = SomeClass.class.getDeclaredField("s");
     }
 
-    @Test
-    public void sanity() {}
-
     @Test
     public void plain() {
         expected = new SomeClass(I_RED, I_RED, S_RED);
@@ -194,16 +194,36 @@ public void copyIntoSubclass() {
         assertEquals(SomeSub.class, actual.getClass());
     }
 
+    @Test
+    public void noValueFound() {
+        sut = new SubjectCreator<>(config, new NoValueProvider(), fieldCache, objenesis);
+
+        ExpectedException
+            .when(() -> sut.plain())
+            .assertThrows(NoValueException.class)
+            .assertDescriptionContains("int");
+
+        assertEquals(expected, actual);
+    }
+
     static class SubjectCreatorTestValueProvider implements ValueProvider {
 
-        public <T> Tuple<T> provide(TypeTag tag) {
+        public <T> Optional<Tuple<T>> provide(TypeTag tag) {
             if (int.class.equals(tag.getType())) {
-                return Tuple.of(I_RED, I_BLUE, I_RED);
+                return Optional.of(Tuple.of(I_RED, I_BLUE, I_RED));
             }
             if (String.class.equals(tag.getType())) {
-                return Tuple.of(S_RED, S_BLUE, new String(S_RED));
+                return Optional.of(Tuple.of(S_RED, S_BLUE, new String(S_RED)));
             }
-            throw new IllegalStateException();
+            return Optional.empty();
+        }
+    }
+
+    static class NoValueProvider implements ValueProvider {
+
+        @Override
+        public <T> Optional<Tuple<T>> provide(TypeTag tag) {
+            return Optional.empty();
         }
     }
 

diff --git a/...va/nl/jqno/equalsverifier/internal/reflection/instantiation/VintageValueProviderTest.java b/...va/nl/jqno/equalsverifier/internal/reflection/instantiation/VintageValueProviderTest.java
@@ -7,9 +7,7 @@
 import static org.junit.jupiter.api.Assertions.assertNotSame;
 import static org.junit.jupiter.api.Assertions.fail;
 
-import java.util.ArrayList;
-import java.util.LinkedHashSet;
-import java.util.List;
+import java.util.*;
 import nl.jqno.equalsverifier.internal.reflection.FactoryCache;
 import nl.jqno.equalsverifier.internal.reflection.Tuple;
 import nl.jqno.equalsverifier.internal.reflection.TypeTag;
@@ -48,8 +46,11 @@ public void sanityTestFactoryIncreasesStringLength() {
 
     @Test
     public void provide() {
-        Tuple<Point> actual = vp.provide(POINT_TAG);
-        assertEquals(Tuple.of(new Point(42, 42), new Point(1337, 1337), new Point(42, 42)), actual);
+        Optional<Tuple<Point>> actual = vp.provide(POINT_TAG);
+        assertEquals(
+            Tuple.of(new Point(42, 42), new Point(1337, 1337), new Point(42, 42)),
+            actual.get()
+        );
     }
 
     @Test