Simplify project dependency resolution

src/main/java/io/github/ascopes/protobufmavenplugin/AbstractGenerateMojo.java

@@ -33,7 +33,6 @@
 import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
-import java.util.Set;
 import java.util.stream.Collectors;
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.plugin.AbstractMojo;
@@ -255,10 +254,9 @@ public abstract class AbstractGenerateMojo extends AbstractMojo {
    * Whether to fail on missing sources.
    *
    * <p>If no sources are detected, it is usually a sign that this plugin
-   * is misconfigured, or that you are including this plugin in a project
-   * that does not need it. For this reason, the plugin defaults this setting
-   * to being enabled. If you wish to not fail, you can explicitly set this
-   * to false instead.
+   * is misconfigured, or that you are including this plugin in a project that does not need it. For
+   * this reason, the plugin defaults this setting to being enabled. If you wish to not fail, you
+   * can explicitly set this to false instead.
    *
    * @since 0.5.0
    */
@@ -310,12 +308,11 @@ public abstract class AbstractGenerateMojo extends AbstractMojo {
   private boolean pythonEnabled;
 
   /**
-   * Enable generating Python stubs ({@code *.pyi} files) for static typechecking
-   * from the protobuf sources.
+   * Enable generating Python stubs ({@code *.pyi} files) for static typechecking from the protobuf
+   * sources.
    *
    * <p>If you enable this, you probably will also want to enable Python itself
-   * to get actual source code
-   * to accompany the stubs.
+   * to get actual source code to accompany the stubs.
    *
    * @since 1.1.0
    */
@@ -384,12 +381,11 @@ public abstract class AbstractGenerateMojo extends AbstractMojo {
   private boolean liteOnly;
 
   /**
-   * Whether to register the output directories as compilation roots with
-   * Maven.
+   * Whether to register the output directories as compilation roots with Maven.
    *
    * <p>Generally, you want to do this, but there may be edge cases where you
-   * wish to control this behaviour manually instead. In this case, set this
-   * parameter to be {@code false}.
+   * wish to control this behaviour manually instead. In this case, set this parameter to be
+   * {@code false}.
    *
    * @since 0.5.0
    */
@@ -410,8 +406,8 @@ public void execute() throws MojoExecutionException, MojoFailureException {
       throw new MojoExecutionException(ex.getMessage(), ex);
     }
 
+    //noinspection DataFlowIssue
     var request = ImmutableGenerationRequest.builder()
-        .allowedDependencyScopes(allowedScopes())
         .binaryMavenPlugins(nonNullList(binaryMavenPlugins))
         .binaryPathPlugins(nonNullList(binaryPathPlugins))
         .binaryUrlPlugins(nonNullList(binaryUrlPlugins))
@@ -499,16 +495,6 @@ private Collection<Path> sourceDirectories() {
    */
   protected abstract Path defaultOutputDirectory(MavenSession session);
 
-  /**
-   * Provides the scopes allowed for dependencies.
-   *
-   * <p>Dependencies matching one of these scopes will be indexed and made visible
-   * to the protoc compiler if proto files are discovered.
-   *
-   * @return a set of the scopes.
-   */
-  protected abstract Set<String> allowedScopes();
-
   /**
    * Validate this Mojo's parameters.
    *

src/main/java/io/github/ascopes/protobufmavenplugin/MainGenerateMojo.java

@@ -22,6 +22,7 @@
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.plugins.annotations.LifecyclePhase;
 import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.ResolutionScope;
 
 /**
  * Generate source code from protobuf files.
@@ -42,6 +43,8 @@
 @Mojo(
     name = "generate",
     defaultPhase = LifecyclePhase.GENERATE_SOURCES,
+    requiresDependencyCollection = ResolutionScope.COMPILE_PLUS_RUNTIME,
+    requiresDependencyResolution = ResolutionScope.COMPILE_PLUS_RUNTIME,
     threadSafe = true
 )
 public final class MainGenerateMojo extends AbstractGenerateMojo {
@@ -51,11 +54,6 @@ protected SourceRootRegistrar sourceRootRegistrar() {
     return SourceRootRegistrar.MAIN;
   }
 
-  @Override
-  protected Set<String> allowedScopes() {
-    return Set.of("compile", "provided", "system");
-  }
-
   @Override
   protected Path defaultSourceDirectory(MavenSession session) {
     return session.getCurrentProject().getBasedir().toPath()

src/main/java/io/github/ascopes/protobufmavenplugin/TestGenerateMojo.java

@@ -22,6 +22,7 @@
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.plugins.annotations.LifecyclePhase;
 import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.ResolutionScope;
 
 /**
  * Generate source code from protobuf files for use in tests.
@@ -47,6 +48,8 @@
 @Mojo(
     name = "generate-test",
     defaultPhase = LifecyclePhase.GENERATE_TEST_SOURCES,
+    requiresDependencyCollection = ResolutionScope.TEST,
+    requiresDependencyResolution = ResolutionScope.TEST,
     threadSafe = true
 )
 public final class TestGenerateMojo extends AbstractGenerateMojo {
@@ -56,11 +59,6 @@ protected SourceRootRegistrar sourceRootRegistrar() {
     return SourceRootRegistrar.TEST;
   }
 
-  @Override
-  protected Set<String> allowedScopes() {
-    return Set.of("compile", "provided", "system", "test");
-  }
-
   @Override
   protected Path defaultSourceDirectory(MavenSession session) {
     return session.getCurrentProject().getBasedir().toPath()

src/main/java/io/github/ascopes/protobufmavenplugin/dependency/JvmPluginResolver.java

@@ -46,8 +46,6 @@
 @Named
 public final class JvmPluginResolver {
 
-  private static final Set<String> SCOPES = Set.of("compile", "runtime", "system");
-
   private final HostSystem hostSystem;
   private final MavenDependencyPathResolver dependencyPathResolver;
   private final TemporarySpace temporarySpace;
@@ -104,7 +102,6 @@ private List<String> resolveAndBuildArgLine(
     var dependencyIterator = dependencyPathResolver
         .resolveDependencyTreePaths(
             session,
-            SCOPES,
             DependencyResolutionDepth.TRANSITIVE,
             plugin
         )

src/main/java/io/github/ascopes/protobufmavenplugin/dependency/MavenDependencyPathResolver.java

@@ -16,15 +16,16 @@
 
 package io.github.ascopes.protobufmavenplugin.dependency;
 
+import java.io.File;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Set;
+import java.util.stream.Collectors;
 import javax.inject.Inject;
 import javax.inject.Named;
+import org.apache.maven.artifact.Artifact;
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.project.DefaultProjectBuildingRequest;
-import org.apache.maven.shared.artifact.filter.resolve.ScopeFilter;
 import org.apache.maven.shared.transfer.artifact.resolve.ArtifactResolver;
 import org.apache.maven.shared.transfer.artifact.resolve.ArtifactResolverException;
 import org.apache.maven.shared.transfer.dependencies.resolve.DependencyResolver;
@@ -56,27 +57,31 @@ public MavenDependencyPathResolver(
 
   public Collection<Path> resolveProjectDependencyPaths(
       MavenSession session,
-      Set<String> allowedScopes,
       DependencyResolutionDepth dependencyResolutionDepth
   ) throws ResolutionException {
-    var paths = new ArrayList<Path>();
-
-    for (var dependency : session.getCurrentProject().getDependencies()) {
-      var artifact = MavenArtifact.fromDependency(dependency);
-      paths.addAll(resolveDependencyTreePaths(
-          session,
-          allowedScopes,
-          dependencyResolutionDepth,
-          artifact
-      ));
+    if (dependencyResolutionDepth == DependencyResolutionDepth.DIRECT) {
+      var artifacts = session.getCurrentProject().getDependencies()
+          .stream()
+          .map(MavenArtifact::fromDependency)
+          .collect(Collectors.toList());
+
+      var paths = new ArrayList<Path>();
+      for (var artifact : artifacts) {
+        paths.add(resolveArtifact(session, artifact));
+      }
+      return paths;
     }
 
-    return paths;
+    return session.getCurrentProject().getArtifacts()
+        .stream()
+        .map(Artifact::getFile)
+        .map(File::toPath)
+        .distinct()
+        .collect(Collectors.toList());
   }
 
   public Collection<Path> resolveDependencyTreePaths(
       MavenSession session,
-      Set<String> allowedScopes,
       DependencyResolutionDepth dependencyResolutionDepth,
       MavenArtifact artifact
   ) throws ResolutionException {
@@ -92,11 +97,10 @@ public Collection<Path> resolveDependencyTreePaths(
     }
 
     var request = new DefaultProjectBuildingRequest(session.getProjectBuildingRequest());
-    var scopes = ScopeFilter.including(allowedScopes);
     var coordinate = artifact.toDependableCoordinate();
 
     try {
-      for (var next : dependencyResolver.resolveDependencies(request, coordinate, scopes)) {
+      for (var next : dependencyResolver.resolveDependencies(request, coordinate, null)) {
         allDependencyPaths.add(next.getArtifact().getFile().toPath());
       }
     } catch (DependencyResolverException ex) {

src/main/java/io/github/ascopes/protobufmavenplugin/generate/GenerationRequest.java

@@ -21,7 +21,6 @@
 import java.net.URL;
 import java.nio.file.Path;
 import java.util.Collection;
-import java.util.Set;
 import org.apache.maven.execution.MavenSession;
 import org.immutables.value.Value.Immutable;
 
@@ -45,8 +44,6 @@ public interface GenerationRequest {
 
   Collection<MavenArtifact> getJvmMavenPlugins();
 
-  Set<String> getAllowedDependencyScopes();
-
   MavenSession getMavenSession();
 
   Path getOutputDirectory();

src/main/java/io/github/ascopes/protobufmavenplugin/generate/SourceCodeGenerator.java

@@ -17,7 +17,6 @@
 package io.github.ascopes.protobufmavenplugin.generate;
 
 import io.github.ascopes.protobufmavenplugin.dependency.BinaryPluginResolver;
-import io.github.ascopes.protobufmavenplugin.dependency.DependencyResolutionDepth;
 import io.github.ascopes.protobufmavenplugin.dependency.JvmPluginResolver;
 import io.github.ascopes.protobufmavenplugin.dependency.MavenDependencyPathResolver;
 import io.github.ascopes.protobufmavenplugin.dependency.ProtocResolver;
@@ -179,7 +178,6 @@ private Collection<ProtoFileListing> discoverImportPaths(
 
     var dependencyPaths = mavenDependencyPathResolver.resolveProjectDependencyPaths(
         session,
-        request.getAllowedDependencyScopes(),
         request.getDependencyResolutionDepth()
     );