pkl-gradle: Migrate nullness to jSpecify (#1530)

pkl-gradle/gradle.lockfile

@@ -16,10 +16,28 @@ com.github.ajalt.mordant:mordant-jvm:3.0.1=compileClasspath
 com.github.ajalt.mordant:mordant:3.0.1=compileClasspath
 com.github.ajalt.mordant:mordant:3.0.2=compileOnlyDependenciesMetadata
 com.github.ben-manes.caffeine:caffeine:2.9.3=swiftExportClasspathResolvable
+com.github.ben-manes.caffeine:caffeine:3.0.5=annotationProcessor,testAnnotationProcessor
+com.github.kevinstern:software-and-algorithms:1.0=annotationProcessor,testAnnotationProcessor
+com.google.auto.service:auto-service-annotations:1.0.1=annotationProcessor,testAnnotationProcessor
+com.google.auto.value:auto-value-annotations:1.9=annotationProcessor,testAnnotationProcessor
+com.google.auto:auto-common:1.2.2=annotationProcessor,testAnnotationProcessor
+com.google.errorprone:error_prone_annotation:2.48.0=annotationProcessor,testAnnotationProcessor
 com.google.errorprone:error_prone_annotations:2.28.0=swiftExportClasspathResolvable
-io.github.java-diff-utils:java-diff-utils:4.12=kotlinInternalAbiValidation
+com.google.errorprone:error_prone_annotations:2.48.0=annotationProcessor,testAnnotationProcessor
+com.google.errorprone:error_prone_check_api:2.48.0=annotationProcessor,testAnnotationProcessor
+com.google.errorprone:error_prone_core:2.48.0=annotationProcessor,testAnnotationProcessor
+com.google.googlejavaformat:google-java-format:1.34.1=annotationProcessor,testAnnotationProcessor
+com.google.guava:failureaccess:1.0.3=annotationProcessor,testAnnotationProcessor
+com.google.guava:guava:33.5.0-jre=annotationProcessor,testAnnotationProcessor
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava=annotationProcessor,testAnnotationProcessor
+com.google.j2objc:j2objc-annotations:3.1=annotationProcessor,testAnnotationProcessor
+com.google.protobuf:protobuf-java:4.33.2=annotationProcessor,testAnnotationProcessor
+com.uber.nullaway:nullaway:0.13.1=annotationProcessor,testAnnotationProcessor
+io.github.eisop:dataflow-errorprone:3.41.0-eisop1=annotationProcessor,testAnnotationProcessor
+io.github.java-diff-utils:java-diff-utils:4.12=annotationProcessor,kotlinInternalAbiValidation,testAnnotationProcessor
 io.opentelemetry:opentelemetry-api:1.41.0=swiftExportClasspathResolvable
 io.opentelemetry:opentelemetry-context:1.41.0=swiftExportClasspathResolvable
+javax.inject:javax.inject:1=annotationProcessor,testAnnotationProcessor
 net.bytebuddy:byte-buddy:1.18.3=testCompileClasspath,testRuntimeClasspath
 org.apiguardian:apiguardian-api:1.1.2=testCompileClasspath
 org.assertj:assertj-core:3.27.7=testCompileClasspath,testRuntimeClasspath
@@ -28,6 +46,8 @@ org.bouncycastle:bcpkix-jdk18on:1.80=kotlinBouncyCastleConfiguration
 org.bouncycastle:bcprov-jdk18on:1.80=kotlinBouncyCastleConfiguration
 org.bouncycastle:bcutil-jdk18on:1.80=kotlinBouncyCastleConfiguration
 org.checkerframework:checker-qual:3.43.0=swiftExportClasspathResolvable
+org.checkerframework:checker-qual:3.53.0=annotationProcessor,testAnnotationProcessor
+org.checkerframework:dataflow-nullaway:3.53.0=annotationProcessor,testAnnotationProcessor
 org.jetbrains.kotlin:abi-tools-api:2.3.20=kotlinInternalAbiValidation
 org.jetbrains.kotlin:abi-tools:2.3.20=kotlinInternalAbiValidation
 org.jetbrains.kotlin:kotlin-build-tools-api:2.3.20=kotlinBuildToolsApiClasspath,kotlinCompilerClasspath
@@ -63,7 +83,7 @@ org.jetbrains.kotlinx:kotlinx-serialization-bom:1.7.3=swiftExportClasspathResolv
 org.jetbrains.kotlinx:kotlinx-serialization-core-jvm:1.7.3=swiftExportClasspathResolvable
 org.jetbrains.kotlinx:kotlinx-serialization-core:1.7.3=swiftExportClasspathResolvable
 org.jetbrains:annotations:13.0=compileClasspath,kotlinBuildToolsApiClasspath,kotlinCompilerClasspath,kotlinCompilerPluginClasspathMain,kotlinCompilerPluginClasspathTest,kotlinInternalAbiValidation,kotlinKlibCommonizerClasspath,swiftExportClasspathResolvable,testCompileClasspath,testRuntimeClasspath
-org.jspecify:jspecify:1.0.0=compileClasspath,testCompileClasspath
+org.jspecify:jspecify:1.0.0=annotationProcessor,compileClasspath,runtimeClasspath,testAnnotationProcessor,testCompileClasspath,testRuntimeClasspath
 org.junit.jupiter:junit-jupiter-api:6.0.3=testCompileClasspath,testRuntimeClasspath
 org.junit.jupiter:junit-jupiter-engine:6.0.3=testCompileClasspath,testRuntimeClasspath
 org.junit.jupiter:junit-jupiter-params:6.0.3=testCompileClasspath,testRuntimeClasspath
@@ -73,4 +93,5 @@ org.junit.platform:junit-platform-launcher:6.0.3=testRuntimeClasspath
 org.junit:junit-bom:6.0.3=testCompileClasspath,testRuntimeClasspath
 org.msgpack:msgpack-core:0.9.11=testRuntimeClasspath
 org.opentest4j:opentest4j:1.3.0=testCompileClasspath,testRuntimeClasspath
-empty=annotationProcessor,apiDependenciesMetadata,implementationDependenciesMetadata,intransitiveDependenciesMetadata,kotlinCompilerPluginClasspath,kotlinNativeCompilerPluginClasspath,kotlinScriptDefExtensions,runtimeClasspath,signatures,sourcesJar,testAnnotationProcessor,testApiDependenciesMetadata,testCompileOnlyDependenciesMetadata,testImplementationDependenciesMetadata,testIntransitiveDependenciesMetadata,testKotlinScriptDefExtensions
+org.pcollections:pcollections:4.0.1=annotationProcessor,testAnnotationProcessor
+empty=apiDependenciesMetadata,implementationDependenciesMetadata,intransitiveDependenciesMetadata,kotlinCompilerPluginClasspath,kotlinNativeCompilerPluginClasspath,kotlinScriptDefExtensions,signatures,sourcesJar,testApiDependenciesMetadata,testCompileOnlyDependenciesMetadata,testImplementationDependenciesMetadata,testIntransitiveDependenciesMetadata,testKotlinScriptDefExtensions

pkl-gradle/pkl-gradle.gradle.kts

@@ -17,7 +17,7 @@ plugins {
   id("pklAllProjects")
   id("pklJavaLibrary")
   id("pklGradlePluginTest")
-
+  id("pklJSpecify")
   `java-gradle-plugin`
   `maven-publish`
   id("pklPublishLibrary")

pkl-gradle/src/main/java/org/pkl/gradle/PklPlugin.java

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2026 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,12 +36,11 @@ import org.gradle.api.tasks.TaskProvider;
 import org.gradle.language.base.plugins.LifecycleBasePlugin;
 import org.gradle.plugins.ide.idea.model.IdeaModel;
 import org.gradle.util.GradleVersion;
+import org.jspecify.annotations.Nullable;
 import org.pkl.cli.CliEvaluatorOptions;
 import org.pkl.core.ImportGraph;
 import org.pkl.core.OutputFormat;
 import org.pkl.core.util.IoUtils;
-import org.pkl.core.util.LateInit;
-import org.pkl.core.util.Nullable;
 import org.pkl.gradle.spec.AnalyzeImportsSpec;
 import org.pkl.gradle.spec.BasePklSpec;
 import org.pkl.gradle.spec.CodeGenSpec;
@@ -71,21 +70,26 @@ public class PklPlugin implements Plugin<Project> {
 
   private static final String MIN_GRADLE_VERSION = "8.2";
 
-  @LateInit private Project project;
+  private @Nullable Project __project;
 
   @Override
   public void apply(Project project) {
-    this.project = project;
+    __project = project;
 
     if (GradleVersion.current().compareTo(GradleVersion.version(MIN_GRADLE_VERSION)) < 0) {
       throw new GradleException(
           String.format("Plugin `org.pkl` requires Gradle %s or higher.", MIN_GRADLE_VERSION));
     }
 
-    var extension = project.getExtensions().create("pkl", PklExtension.class);
+    var extension = project().getExtensions().create("pkl", PklExtension.class);
     configureExtension(extension);
   }
 
+  private Project project() {
+    assert __project != null;
+    return __project;
+  }
+
   private void configureExtension(PklExtension extension) {
     configureEvalTasks(extension.getEvaluators());
     configureJavaCodeGenTasks(extension.getJavaCodeGenerators());
@@ -102,7 +106,7 @@ public class PklPlugin implements Plugin<Project> {
         spec -> {
           configureBaseSpec(spec);
           spec.getOutputPath()
-              .convention(project.getLayout().getBuildDirectory().dir("generated/pkl/packages"));
+              .convention(project().getLayout().getBuildDirectory().dir("generated/pkl/packages"));
           spec.getOverwrite().convention(false);
           var packageTask = createTask(ProjectPackageTask.class, spec);
           packageTask.configure(
@@ -113,12 +117,12 @@ public class PklPlugin implements Plugin<Project> {
                 task.getJunitReportsDir().set(spec.getJunitReportsDir());
                 task.getOverwrite().set(spec.getOverwrite());
               });
-          project
+          project()
               .getPluginManager()
               .withPlugin(
                   "base",
                   appliedPlugin ->
-                      project
+                      project()
                           .getTasks()
                           .named(
                               LifecycleBasePlugin.BUILD_TASK_NAME,
@@ -157,7 +161,7 @@ public class PklPlugin implements Plugin<Project> {
           configureBaseSpec(spec);
           spec.getOutputFile()
               .convention(
-                  project
+                  project()
                       .getLayout()
                       .getProjectDirectory()
                       // %{moduleDir} is resolved relatively to the working directory,
@@ -194,11 +198,12 @@ public class PklPlugin implements Plugin<Project> {
           // constructor parameters annotations by setting this property to `null`.
           spec.getParamsAnnotation()
               .set(
-                  project.provider(
+                  project()
-                      () ->
+                      .provider(
-                          spec.getGenerateSpringBootConfig().get()
+                          () ->
-                              ? null
+                              spec.getGenerateSpringBootConfig().get()
-                              : "org.pkl.config.java.mapper.Named"));
+                                  ? null
+                                  : "org.pkl.config.java.mapper.Named"));
 
           createModulesTask(JavaCodeGenTask.class, spec)
               .configure(
@@ -211,14 +216,15 @@ public class PklPlugin implements Plugin<Project> {
                   });
         });
 
-    project.afterEvaluate(
+    project()
-        prj ->
+        .afterEvaluate(
-            specs.all(
+            prj ->
-                spec -> {
+                specs.all(
-                  configureIdeaModule(spec);
+                    spec -> {
-                  configureCodeGenSpecSourceDirectories(
+                      configureIdeaModule(spec);
-                      spec, "java", s -> Optional.of(s.getJava()));
+                      configureCodeGenSpecSourceDirectories(
-                }));
+                          spec, "java", s -> Optional.of(s.getJava()));
+                    }));
   }
 
   private void configureKotlinCodeGenTasks(NamedDomainObjectContainer<KotlinCodeGenSpec> specs) {
@@ -237,14 +243,15 @@ public class PklPlugin implements Plugin<Project> {
                   });
         });
 
-    project.afterEvaluate(
+    project()
-        prj ->
+        .afterEvaluate(
-            specs.all(
+            prj ->
-                spec -> {
+                specs.all(
-                  configureIdeaModule(spec);
+                    spec -> {
-                  configureCodeGenSpecSourceDirectories(
+                      configureIdeaModule(spec);
-                      spec, "kotlin", this::getKotlinSourceDirectorySet);
+                      configureCodeGenSpecSourceDirectories(
-                }));
+                          spec, "kotlin", this::getKotlinSourceDirectorySet);
+                    }));
   }
 
   private void configurePkldocTasks(NamedDomainObjectContainer<PkldocSpec> specs) {
@@ -254,7 +261,7 @@ public class PklPlugin implements Plugin<Project> {
 
           spec.getOutputDir()
               .convention(
-                  project
+                  project()
                       .getLayout()
                       .getBuildDirectory()
                       .map(it -> it.dir("pkldoc").dir(spec.getName())));
@@ -284,12 +291,12 @@ public class PklPlugin implements Plugin<Project> {
                 task.getOverwrite().set(spec.getOverwrite());
               });
 
-          project
+          project()
               .getPluginManager()
               .withPlugin(
                   "base",
                   appliedPlugin ->
-                      project
+                      project()
                           .getTasks()
                           .named(
                               LifecycleBasePlugin.CHECK_TASK_NAME,
@@ -306,7 +313,7 @@ public class PklPlugin implements Plugin<Project> {
     spec.getAllowedResources()
         .convention(List.of("env:", "prop:", "file:", "modulepath:", "https:", "package:"));
 
-    spec.getEvalRootDir().convention(project.getRootProject().getLayout().getProjectDirectory());
+    spec.getEvalRootDir().convention(project().getRootProject().getLayout().getProjectDirectory());
 
     // Defaulting to OS env vars is bad for reproducibility and cachability.
     // Hence, this spec defaults to empty env vars, which is consistent with other Gradle tasks
@@ -326,18 +333,19 @@ public class PklPlugin implements Plugin<Project> {
   private void configureCodeGenSpec(CodeGenSpec spec) {
     spec.getOutputDir()
         .convention(
-            project
+            project()
                 .getLayout()
                 .getBuildDirectory()
                 .map(it -> it.dir("generated").dir("pkl").dir(spec.getName())));
 
     spec.getSourceSet()
         .convention(
-            project
+            project()
                 .getProviders()
                 .provider(
                     () -> {
-                      var sourceSets = project.getExtensions().findByType(SourceSetContainer.class);
+                      var sourceSets =
+                          project().getExtensions().findByType(SourceSetContainer.class);
                       if (sourceSets == null) {
                         return null;
                       }
@@ -371,7 +379,7 @@ public class PklPlugin implements Plugin<Project> {
     // Refer to configureCodeGenSpecSourceDirectories for logic which links the codegen task
     // to sourceSet.getResources().getSourceDirectories().
 
-    var modulePath = project.files();
+    var modulePath = project().files();
     modulePath
         .from(getResourceSourceDirectoriesExceptSpecOutput(spec))
         // This technically breaks the dependency on compile classpath builder tasks,
@@ -411,14 +419,14 @@ public class PklPlugin implements Plugin<Project> {
       String languageName,
       Function<? super SourceSet, ? extends Optional<SourceDirectorySet>>
           extractSourceDirectorySet) {
-    var task = project.getTasks().named(spec.getName(), CodeGenTask.class);
+    var task = project().getTasks().named(spec.getName(), CodeGenTask.class);
     var sourceSet = spec.getSourceSet().get();
     extractSourceDirectorySet
         .apply(sourceSet)
         .ifPresentOrElse(
             dirSet -> dirSet.srcDir(task.flatMap(t -> t.getOutputDir().dir(languageName))),
             () ->
-                project
+                project()
                     .getLogger()
                     .debug(
                         "Source directory set for language {} is not available, "
@@ -431,12 +439,12 @@ public class PklPlugin implements Plugin<Project> {
   // Must be called from Project.afterEvaluate() only, because this method depends
   // on user-provided configuration not accessible with lazy configuration.
   private void configureIdeaModule(CodeGenSpec spec) {
-    project
+    project()
         .getPluginManager()
         .withPlugin(
             "idea",
             plugin -> {
-              var module = project.getExtensions().getByType(IdeaModel.class).getModule();
+              var module = project().getExtensions().getByType(IdeaModel.class).getModule();
               var outputDir = spec.getOutputDir().get().getAsFile();
               module.getGeneratedSourceDirs().add(outputDir);
               if (spec.getSourceSet().get().getName().toLowerCase().contains("test")) {
@@ -521,11 +529,11 @@ public class PklPlugin implements Plugin<Project> {
 
   private TaskProvider<AnalyzeImportsTask> createAnalyzeImportsTask(ModulesSpec spec) {
     var outputFile =
-        project
+        project()
             .getLayout()
             .getBuildDirectory()
             .file("pkl-gradle/imports/" + spec.getName() + ".json");
-    return project
+    return project()
         .getTasks()
         .register(
             spec.getName() + "GatherImports",
@@ -567,7 +575,7 @@ public class PklPlugin implements Plugin<Project> {
   private <T extends ModulesTask> TaskProvider<T> createModulesTask(
       Class<T> taskClass, ModulesSpec spec) {
     var analyzeImportsTask = createAnalyzeImportsTask(spec);
-    return project
+    return project()
         .getTasks()
         .register(
             spec.getName(),
@@ -576,7 +584,7 @@ public class PklPlugin implements Plugin<Project> {
   }
 
   private <T extends BasePklTask> TaskProvider<T> createTask(Class<T> taskClass, BasePklSpec spec) {
-    return project
+    return project()
         .getTasks()
         .register(spec.getName(), taskClass, task -> configureBaseTask(task, spec));
   }

pkl-gradle/src/main/java/org/pkl/gradle/package-info.java

@@ -1,4 +1,4 @@
-@NonnullByDefault
+@NullMarked
 package org.pkl.gradle;
 
-import org.pkl.core.util.NonnullByDefault;
+import org.jspecify.annotations.NullMarked;

pkl-gradle/src/main/java/org/pkl/gradle/spec/package-info.java

@@ -1,4 +1,4 @@
-@NonnullByDefault
+@NullMarked
 package org.pkl.gradle.spec;
 
-import org.pkl.core.util.NonnullByDefault;
+import org.jspecify.annotations.NullMarked;

pkl-gradle/src/main/java/org/pkl/gradle/task/BasePklTask.java

@@ -28,6 +28,7 @@ import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import javax.inject.Inject;
 import org.gradle.api.DefaultTask;
+import org.gradle.api.Transformer;
 import org.gradle.api.file.ConfigurableFileCollection;
 import org.gradle.api.file.DirectoryProperty;
 import org.gradle.api.model.ObjectFactory;
@@ -45,10 +46,9 @@ import org.gradle.api.tasks.Optional;
 import org.gradle.api.tasks.PathSensitive;
 import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.TaskAction;
+import org.jspecify.annotations.Nullable;
 import org.pkl.commons.cli.CliBaseOptions;
 import org.pkl.core.evaluatorSettings.Color;
-import org.pkl.core.util.LateInit;
-import org.pkl.core.util.Nullable;
 import org.pkl.gradle.utils.PluginUtils;
 
 @CacheableTask
@@ -86,27 +86,21 @@ public abstract class BasePklTask extends DefaultTask {
   @Optional
   @PathSensitive(PathSensitivity.ABSOLUTE)
   public Provider<File> getSettingsModuleFile() {
+    //noinspection RedundantCast
     return getParsedSettingsModule()
+        // NullAway needs this redundant cast
         .map(
-            it -> {
+            (Transformer<@Nullable File, Object>)
-              if (it instanceof File file) {
+                object -> object instanceof File file ? file : null);
-                return file;
-              }
-              return null;
-            });
   }
 
   @Input
   @Optional
   public Provider<URI> getSettingsModuleUri() {
+    //noinspection RedundantCast
     return getParsedSettingsModule()
-        .map(
+        // NullAway needs this redundant cast
-            it -> {
+        .map((Transformer<@Nullable URI, Object>) object -> object instanceof URI uri ? uri : null);
-              if (it instanceof URI uri) {
-                return uri;
-              }
-              return null;
-            });
   }
 
   // Exposed as a task input via evalRootDirPath, because we only need to depend
@@ -180,13 +174,13 @@ public abstract class BasePklTask extends DefaultTask {
 
   protected abstract void doRunTask();
 
-  @LateInit protected CliBaseOptions cachedOptions;
+  protected @Nullable CliBaseOptions __cachedOptions;
 
   // Must be called during task execution time only.
   @Internal
   protected CliBaseOptions getCliBaseOptions() {
-    if (cachedOptions == null) {
+    if (__cachedOptions == null) {
-      cachedOptions =
+      __cachedOptions =
           new CliBaseOptions(
               getSourceModulesAsUris(),
               patternsFromStrings(getAllowedModules().get()),
@@ -215,7 +209,7 @@ public abstract class BasePklTask extends DefaultTask {
               null,
               getPowerAssertions().getOrElse(false));
     }
-    return cachedOptions;
+    return __cachedOptions;
   }
 
   @Internal

pkl-gradle/src/main/java/org/pkl/gradle/task/ModulesTask.java

@@ -145,8 +145,8 @@ public abstract class ModulesTask extends BasePklTask {
   @Internal
   @Override
   protected CliBaseOptions getCliBaseOptions() {
-    if (cachedOptions == null) {
+    if (__cachedOptions == null) {
-      cachedOptions =
+      __cachedOptions =
           new CliBaseOptions(
               getSourceModulesAsUris(),
               patternsFromStrings(getAllowedModules().get()),
@@ -175,6 +175,6 @@ public abstract class ModulesTask extends BasePklTask {
               null,
               getPowerAssertions().getOrElse(false));
     }
-    return cachedOptions;
+    return __cachedOptions;
   }
 }

pkl-gradle/src/main/java/org/pkl/gradle/task/package-info.java

@@ -1,4 +1,4 @@
-@NonnullByDefault
+@NullMarked
 package org.pkl.gradle.task;
 
-import org.pkl.core.util.NonnullByDefault;
+import org.jspecify.annotations.NullMarked;

pkl-gradle/src/main/java/org/pkl/gradle/utils/package-info.java

@@ -1,4 +1,4 @@
-@NonnullByDefault
+@NullMarked
 package org.pkl.gradle.utils;
 
-import org.pkl.core.util.NonnullByDefault;
+import org.jspecify.annotations.NullMarked;