Use more fluent streams constructs.

Previously we avoided collectors like `toImmutableList()` because of Google-internal problems where sometimes we would end up with a version of Guava that didn't include those methods. Now we have copies of the methods in `MoreStreams` so we can use those.

RELNOTES=n/a
PiperOrigin-RevId: 381898090

6 files changed, 28 insertions, 34 deletions

diff --git a/common/src/main/java/com/google/auto/common/BasicAnnotationProcessor.java b/common/src/main/java/com/google/auto/common/BasicAnnotationProcessor.java
index 31336cc3..92a72c49 100644
--- a/common/src/main/java/com/google/auto/common/BasicAnnotationProcessor.java
+++ b/common/src/main/java/com/google/auto/common/BasicAnnotationProcessor.java
@@ -17,14 +17,13 @@ package com.google.auto.common;
 
 import static com.google.auto.common.MoreElements.asExecutable;
 import static com.google.auto.common.MoreElements.asPackage;
+import static com.google.auto.common.MoreStreams.toImmutableMap;
+import static com.google.auto.common.MoreStreams.toImmutableSet;
 import static com.google.auto.common.SuperficialValidation.validateElement;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.collect.Iterables.transform;
 import static com.google.common.collect.Multimaps.filterKeys;
-import static java.util.stream.Collectors.collectingAndThen;
-import static java.util.stream.Collectors.toList;
-import static java.util.stream.Collectors.toMap;
 import static javax.lang.model.element.ElementKind.PACKAGE;
 import static javax.tools.Diagnostic.Kind.ERROR;
 
@@ -162,14 +161,14 @@ public abstract class BasicAnnotationProcessor extends AbstractProcessor {
     checkState(steps != null);
     return steps.stream()
         .flatMap(step -> getSupportedAnnotationTypeElements(step).stream())
-        .collect(collectingAndThen(toList(), ImmutableSet::copyOf));
+        .collect(toImmutableSet());
   }
 
   private ImmutableSet<TypeElement> getSupportedAnnotationTypeElements(Step step) {
     return step.annotations().stream()
         .map(elements::getTypeElement)
         .filter(Objects::nonNull)
-        .collect(collectingAndThen(toList(), ImmutableSet::copyOf));
+        .collect(toImmutableSet());
   }
 
   /**
@@ -181,7 +180,7 @@ public abstract class BasicAnnotationProcessor extends AbstractProcessor {
     checkState(steps != null);
     return steps.stream()
         .flatMap(step -> step.annotations().stream())
-        .collect(collectingAndThen(toList(), ImmutableSet::copyOf));
+        .collect(toImmutableSet());
   }
 
   @Override
@@ -478,10 +477,8 @@ public abstract class BasicAnnotationProcessor extends AbstractProcessor {
       this.annotationsByName =
           processingStep.annotations().stream()
               .collect(
-                  collectingAndThen(
-                      toMap(
-                          Class::getCanonicalName, (Class<? extends Annotation> aClass) -> aClass),
-                      ImmutableMap::copyOf));
+                  toImmutableMap(
+                      Class::getCanonicalName, (Class<? extends Annotation> aClass) -> aClass));
     }
 
     @Override
diff --git a/common/src/main/java/com/google/auto/common/MoreElements.java b/common/src/main/java/com/google/auto/common/MoreElements.java
index 8061cd57..c8a478a4 100644
--- a/common/src/main/java/com/google/auto/common/MoreElements.java
+++ b/common/src/main/java/com/google/auto/common/MoreElements.java
@@ -16,6 +16,7 @@
  */
 package com.google.auto.common;
 
+import static com.google.auto.common.MoreStreams.toImmutableSet;
 import static javax.lang.model.element.ElementKind.PACKAGE;
 import static javax.lang.model.element.Modifier.STATIC;
 
@@ -482,9 +483,9 @@ public final class MoreElements {
         }
       }
     }
-    Set<ExecutableElement> methods = new LinkedHashSet<ExecutableElement>(methodMap.values());
-    methods.removeAll(overridden);
-    return ImmutableSet.copyOf(methods);
+    return methodMap.values().stream()
+        .filter(m -> !overridden.contains(m))
+        .collect(toImmutableSet());
   }
 
   // Add to `methods` the static and instance methods from `type`. This means all methods from
diff --git a/value/src/it/functional/src/test/java/com/google/auto/value/AutoAnnotationTest.java b/value/src/it/functional/src/test/java/com/google/auto/value/AutoAnnotationTest.java
index f894d6b9..aec89287 100644
--- a/value/src/it/functional/src/test/java/com/google/auto/value/AutoAnnotationTest.java
+++ b/value/src/it/functional/src/test/java/com/google/auto/value/AutoAnnotationTest.java
@@ -116,7 +116,7 @@ public class AutoAnnotationTest {
     assertThat(arrays.ints()).asList().containsExactly(2, 3, 5).inOrder();
     strings[0] = "Hyde";
     ints[0] = -1;
-    assertThat(ImmutableList.copyOf(arrays.strings())).containsExactly("Jekyll");
+    assertThat(arrays.strings()).asList().containsExactly("Jekyll");
     assertThat(arrays.ints()).asList().containsExactly(2, 3, 5).inOrder();
   }
 
diff --git a/value/src/main/java/com/google/auto/value/processor/AutoValueProcessor.java b/value/src/main/java/com/google/auto/value/processor/AutoValueProcessor.java
index 837fc573..ab7da924 100644
--- a/value/src/main/java/com/google/auto/value/processor/AutoValueProcessor.java
+++ b/value/src/main/java/com/google/auto/value/processor/AutoValueProcessor.java
@@ -16,12 +16,12 @@
 package com.google.auto.value.processor;
 
 import static com.google.auto.common.MoreElements.getLocalAndInheritedMethods;
+import static com.google.auto.common.MoreStreams.toImmutableList;
 import static com.google.auto.value.processor.ClassNames.AUTO_VALUE_NAME;
 import static com.google.common.collect.Sets.difference;
 import static com.google.common.collect.Sets.intersection;
 import static java.util.Comparator.naturalOrder;
 import static java.util.stream.Collectors.joining;
-import static java.util.stream.Collectors.toList;
 
 import com.google.auto.service.AutoService;
 import com.google.auto.value.extension.AutoValueExtension;
@@ -33,7 +33,6 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.Iterables;
 import java.lang.annotation.Annotation;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -100,10 +99,9 @@ public class AutoValueProcessor extends AutoValueishProcessor {
 
   @VisibleForTesting
   static ImmutableList<AutoValueExtension> extensionsFromLoader(ClassLoader loader) {
-    return ImmutableList.copyOf(
-        Iterables.filter(
-            SimpleServiceLoader.load(AutoValueExtension.class, loader),
-            ext -> !ext.getClass().getName().equals(OLD_MEMOIZE_EXTENSION)));
+    return SimpleServiceLoader.load(AutoValueExtension.class, loader).stream()
+        .filter(ext -> !ext.getClass().getName().equals(OLD_MEMOIZE_EXTENSION))
+        .collect(toImmutableList());
   }
 
   @Override
@@ -428,9 +426,8 @@ public class AutoValueProcessor extends AutoValueishProcessor {
       ImmutableMap<ExecutableElement, TypeMirror> propertyMethodsAndTypes,
       Optional<BuilderSpec.Builder> maybeBuilder) {
     ImmutableSet<ExecutableElement> propertyMethods = propertyMethodsAndTypes.keySet();
-    // We can't use ImmutableList.toImmutableList() for obscure Google-internal reasons.
     vars.toBuilderMethods =
-        ImmutableList.copyOf(toBuilderMethods.stream().map(SimpleMethod::new).collect(toList()));
+        toBuilderMethods.stream().map(SimpleMethod::new).collect(toImmutableList());
     vars.toBuilderConstructor = !vars.toBuilderMethods.isEmpty();
     ImmutableListMultimap<ExecutableElement, AnnotationMirror> annotatedPropertyFields =
         propertyFieldAnnotationMap(type, propertyMethods);
diff --git a/value/src/main/java/com/google/auto/value/processor/AutoValueishProcessor.java b/value/src/main/java/com/google/auto/value/processor/AutoValueishProcessor.java
index 3f949f5b..93f2f79e 100644
--- a/value/src/main/java/com/google/auto/value/processor/AutoValueishProcessor.java
+++ b/value/src/main/java/com/google/auto/value/processor/AutoValueishProcessor.java
@@ -19,6 +19,7 @@ import static com.google.auto.common.AnnotationMirrors.getAnnotationValue;
 import static com.google.auto.common.GeneratedAnnotations.generatedAnnotation;
 import static com.google.auto.common.MoreElements.getPackage;
 import static com.google.auto.common.MoreElements.isAnnotationPresent;
+import static com.google.auto.common.MoreStreams.toImmutableList;
 import static com.google.auto.common.MoreStreams.toImmutableSet;
 import static com.google.auto.value.processor.ClassNames.AUTO_VALUE_PACKAGE_NAME;
 import static com.google.auto.value.processor.ClassNames.COPY_ANNOTATIONS_NAME;
@@ -467,8 +468,9 @@ abstract class AutoValueishProcessor extends AbstractProcessor {
   /** Returns the spelling to be used in the generated code for the given list of annotations. */
   static ImmutableList<String> annotationStrings(List<? extends AnnotationMirror> annotations) {
     // TODO(b/68008628): use ImmutableList.toImmutableList() when that works.
-    return ImmutableList.copyOf(
-        annotations.stream().map(AnnotationOutput::sourceFormForAnnotation).collect(toList()));
+    return annotations.stream()
+        .map(AnnotationOutput::sourceFormForAnnotation)
+        .collect(toImmutableList());
   }
 
   /**
diff --git a/value/src/main/java/com/google/auto/value/processor/BuilderSpec.java b/value/src/main/java/com/google/auto/value/processor/BuilderSpec.java
index 017a5ff5..9f45d172 100644
--- a/value/src/main/java/com/google/auto/value/processor/BuilderSpec.java
+++ b/value/src/main/java/com/google/auto/value/processor/BuilderSpec.java
@@ -16,6 +16,7 @@
 package com.google.auto.value.processor;
 
 import static com.google.auto.common.MoreElements.getLocalAndInheritedMethods;
+import static com.google.auto.common.MoreStreams.toImmutableSet;
 import static com.google.auto.value.processor.AutoValueishProcessor.hasAnnotationMirror;
 import static com.google.auto.value.processor.AutoValueishProcessor.nullableAnnotationFor;
 import static com.google.auto.value.processor.ClassNames.AUTO_VALUE_BUILDER_NAME;
@@ -35,7 +36,6 @@ import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Maps;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -330,15 +330,12 @@ class BuilderSpec {
       vars.builderPropertyBuilders =
           ImmutableMap.copyOf(classifier.propertyNameToPropertyBuilder());
 
-      Set<Property> required = new LinkedHashSet<>(vars.props);
-      for (Property property : vars.props) {
-        if (property.isNullable()
-            || property.getOptional() != null
-            || vars.builderPropertyBuilders.containsKey(property.getName())) {
-          required.remove(property);
-        }
-      }
-      vars.builderRequiredProperties = ImmutableSet.copyOf(required);
+      vars.builderRequiredProperties =
+          vars.props.stream()
+              .filter(p -> !p.isNullable())
+              .filter(p -> p.getOptional() == null)
+              .filter(p -> !vars.builderPropertyBuilders.containsKey(p.getName()))
+              .collect(toImmutableSet());
     }
   }