# HG changeset patch
# User cin
# Date 2026-04-21 18:55:26
# Node ID 780370baa54c1055b902596f328af69181b08840
# Parent  a4138749793f886f24b03ba14a82a395c90f445c

variants: move source set layout conventions out of model

Keep GenericSourceSet convention-free and apply layout defaults from SourcesPlugin and VariantSourcesPlugin.

Add compile unit layout convention and cover standalone and variant source set layouts in functional tests.

diff --git a/.vscode/settings.json b/.vscode/settings.json
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -4,6 +4,7 @@
     "cSpell.words": [
         "implab",
         "materializer",
-        "rawtypes"
+        "rawtypes",
+        "Replayable"
     ]
 }
\ No newline at end of file
diff --git a/variants/src/main/java/org/implab/gradle/variants/SourcesPlugin.java b/variants/src/main/java/org/implab/gradle/variants/SourcesPlugin.java
--- a/variants/src/main/java/org/implab/gradle/variants/SourcesPlugin.java
+++ b/variants/src/main/java/org/implab/gradle/variants/SourcesPlugin.java
@@ -6,6 +6,7 @@ import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.logging.Logger;
 import org.gradle.api.logging.Logging;
+import org.implab.gradle.common.core.lang.FilePaths;
 import org.implab.gradle.variants.sources.GenericSourceSet;
 
 /**
@@ -16,12 +17,27 @@ import org.implab.gradle.variants.source
 public abstract class SourcesPlugin implements Plugin<Project> {
     private static final Logger logger = Logging.getLogger(SourcesPlugin.class);
 
-    private static final String SOURCES_EXTENSION_NAME = "sources";
+    public static final String SOURCES_EXTENSION_NAME = "sources";
+
+    private static final String SOURCES_DIRECTORY = "src";
+
+    private static final String OUTPUTS_DIRECTORY = "out";
 
     @Override
     public void apply(Project target) {
         logger.debug("Registering '{}' extension on project '{}'", SOURCES_EXTENSION_NAME, target.getPath());
+
+        var layout = target.getLayout();
+
         var sources = target.getObjects().domainObjectContainer(GenericSourceSet.class);
+        sources.configureEach(sourceSet -> {
+            sourceSet.getSourceSetDir()
+                    .convention(layout.getProjectDirectory()
+                            .dir(FilePaths.cat(SOURCES_DIRECTORY, sourceSet.getName())));
+            sourceSet.getOutputsDir()
+                    .convention(layout.getBuildDirectory()
+                            .dir(FilePaths.cat(OUTPUTS_DIRECTORY, sourceSet.getName())));
+        });
         target.getExtensions().add(SOURCES_EXTENSION_NAME, sources);
     }
 
@@ -32,7 +48,8 @@ public abstract class SourcesPlugin impl
         var extension = (NamedDomainObjectContainer<GenericSourceSet>) extensions.findByName(SOURCES_EXTENSION_NAME);
 
         if (extension == null) {
-            logger.error("Sources extension '{}' isn't found on project '{}'", SOURCES_EXTENSION_NAME, target.getPath());
+            logger.error("Sources extension '{}' isn't found on project '{}'", SOURCES_EXTENSION_NAME,
+                    target.getPath());
             throw new GradleException("Sources extension isn't found");
         }
         logger.debug("Resolved '{}' extension on project '{}'", SOURCES_EXTENSION_NAME, target.getPath());
diff --git a/variants/src/main/java/org/implab/gradle/variants/VariantArtifactsPlugin.java b/variants/src/main/java/org/implab/gradle/variants/VariantArtifactsPlugin.java
--- a/variants/src/main/java/org/implab/gradle/variants/VariantArtifactsPlugin.java
+++ b/variants/src/main/java/org/implab/gradle/variants/VariantArtifactsPlugin.java
@@ -21,6 +21,7 @@ import org.implab.gradle.variants.source
 import org.implab.gradle.variants.artifacts.OutgoingConfigurationSlotSpec;
 
 public abstract class VariantArtifactsPlugin implements Plugin<Project> {
+    public static final String VARIANT_ARTIFACTS_EXTENSION = "variantArtifacts";
 
     @Override
     public void apply(Project target) {
@@ -105,7 +106,7 @@ public abstract class VariantArtifactsPl
 
         };
 
-        extensions.add(VariantArtifactsExtension.class, "variantArtifacts", variantArtifacts);
+        extensions.add(VariantArtifactsExtension.class, VARIANT_ARTIFACTS_EXTENSION, variantArtifacts);
 
     }
 
diff --git a/variants/src/main/java/org/implab/gradle/variants/VariantSourcesPlugin.java b/variants/src/main/java/org/implab/gradle/variants/VariantSourcesPlugin.java
--- a/variants/src/main/java/org/implab/gradle/variants/VariantSourcesPlugin.java
+++ b/variants/src/main/java/org/implab/gradle/variants/VariantSourcesPlugin.java
@@ -1,12 +1,9 @@
 package org.implab.gradle.variants;
 
 import java.util.Objects;
-import java.util.function.Predicate;
 
 import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.gradle.api.Action;
-import org.gradle.api.InvalidUserDataException;
-import org.gradle.api.Named;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.implab.gradle.common.core.lang.Deferred;
@@ -14,13 +11,13 @@ import org.implab.gradle.common.core.lan
 import org.implab.gradle.variants.core.Layer;
 import org.implab.gradle.variants.core.Variant;
 import org.implab.gradle.variants.core.VariantsExtension;
-import org.implab.gradle.variants.core.VariantsView;
 import org.implab.gradle.variants.sources.CompileUnit;
 import org.implab.gradle.variants.sources.CompileUnitSourceSetSpec;
 import org.implab.gradle.variants.sources.CompileUnitsView;
 import org.implab.gradle.variants.sources.RoleProjectionsView;
 import org.implab.gradle.variants.sources.VariantSourcesContext;
 import org.implab.gradle.variants.sources.VariantSourcesExtension;
+import org.implab.gradle.variants.sources.internal.CompileUnitLayoutConvention;
 import org.implab.gradle.variants.sources.internal.CompileUnitNamer;
 import org.implab.gradle.variants.sources.internal.DefaultCompileUnitNamingPolicy;
 import org.implab.gradle.variants.sources.internal.DefaultLateConfigurationPolicySpec;
@@ -32,6 +29,10 @@ import org.implab.gradle.variants.source
 public abstract class VariantSourcesPlugin implements Plugin<Project> {
     public static final String VARIANT_SOURCES_EXTENSION = "variantSources";
 
+    private static final String VARIANT_OUTPUTS_DIRECTORY = "variants";
+
+    private static final String VARIANT_SOURCES_DIRECTORY = "src";
+
     @Override
     public void apply(Project target) {
         var extensions = target.getExtensions();
@@ -40,7 +41,8 @@ public abstract class VariantSourcesPlug
         target.getPlugins().apply(VariantsPlugin.class);
         // Access the VariantsExtension to configure variant sources.
         var variantsExtension = extensions.getByType(VariantsExtension.class);
-        var objectFactory = target.getObjects();
+        var objects = target.getObjects();
+        var providers = target.getProviders();
 
         var deferred = new Deferred<VariantSourcesContext>();
 
@@ -53,25 +55,31 @@ public abstract class VariantSourcesPlug
             var roleProjections = RoleProjectionsView.of(variants);
 
             // create registries
-            var sourceSetRegistry = new SourceSetRegistry(objectFactory);
+            var sourceSetRegistry = new SourceSetRegistry(objects);
             lateConfigurationPolicy.finalizePolicy();
             var sourceSetConfiguration = new SourceSetConfigurationRegistry(lateConfigurationPolicy::mode);
 
             // build compile unit namer
             var compileUnitNamer = CompileUnitNamer.builder()
-                .addUnits(compileUnits.getUnits())
-                .nameCollisionPolicy(namingPolicy.policy())
-                .build();
+                    .addUnits(compileUnits.getUnits())
+                    .nameCollisionPolicy(namingPolicy.policy())
+                    .build();
+
+            var compileUnitLayoutConvention = new CompileUnitLayoutConvention(
+                    providers.provider(() -> target.getLayout().getProjectDirectory().dir(VARIANT_SOURCES_DIRECTORY)),
+                    target.getLayout().getBuildDirectory().dir(VARIANT_OUTPUTS_DIRECTORY));
+
+            // apply layout convention to all compile unit source sets
+            sourceSetConfiguration.addAction(compileUnitLayoutConvention);
 
             // create the context
             var context = new DefaultVariantSourcesContext(
-                variants,
-                compileUnits,
-                roleProjections,
-                compileUnitNamer,
-                sourceSetRegistry,
-                sourceSetConfiguration
-            );
+                    variants,
+                    compileUnits,
+                    roleProjections,
+                    compileUnitNamer,
+                    sourceSetRegistry,
+                    sourceSetConfiguration);
             deferred.resolve(context);
         });
 
@@ -98,7 +106,9 @@ public abstract class VariantSourcesPlug
 
                 lateConfigurationPolicy.finalizePolicy();
 
-                whenAvailable(ctx -> ctx.configureVariant(resolveVariant(ctx.getVariants(), variantName), action));
+                var variant = objects.named(Variant.class, variantName);
+
+                whenAvailable(ctx -> ctx.configureVariant(variant, action));
             }
 
             @Override
@@ -109,7 +119,9 @@ public abstract class VariantSourcesPlug
 
                 lateConfigurationPolicy.finalizePolicy();
 
-                whenAvailable(ctx -> ctx.configureLayer(resolveLayer(ctx.getVariants(), layerName), action));
+                var layer = objects.named(Layer.class, layerName);
+
+                whenAvailable(ctx -> ctx.configureLayer(layer, action));
             }
 
             @Override
@@ -120,7 +132,11 @@ public abstract class VariantSourcesPlug
 
                 lateConfigurationPolicy.finalizePolicy();
 
-                whenAvailable(ctx -> ctx.configureUnit(resolveCompileUnit(ctx, variantName, layerName), action));
+                var variant = objects.named(Variant.class, variantName);
+                var layer = objects.named(Layer.class, layerName);
+                var unit = new CompileUnit(variant, layer);
+
+                whenAvailable(ctx -> ctx.configureUnit(unit, action));
             }
 
             @Override
@@ -136,31 +152,4 @@ public abstract class VariantSourcesPlug
         extensions.add(VariantSourcesExtension.class, VARIANT_SOURCES_EXTENSION, variantSourcesExtension);
 
     }
-
-    private static Layer resolveLayer(VariantsView variants, String name) {
-        return variants.getLayers().stream()
-                .filter(named(name))
-                .findAny()
-                .orElseThrow(() -> new InvalidUserDataException("Layer '" + name + "' isn't declared"));
-    }
-
-    private static Variant resolveVariant(VariantsView variants, String name) {
-        return variants.getVariants().stream()
-                .filter(named(name))
-                .findAny()
-                .orElseThrow(() -> new InvalidUserDataException("Variant '" + name + "' isn't declared"));
-    }
-
-    private static CompileUnit resolveCompileUnit(VariantSourcesContext ctx, String variantName, String layerName) {
-        return ctx.getCompileUnits().findUnit(
-                resolveVariant(ctx.getVariants(), variantName),
-                resolveLayer(ctx.getVariants(), layerName))
-                .orElseThrow(() -> new InvalidUserDataException(
-                        "The CompileUnit isn't declared for variant '" + variantName + "', layer '" + layerName + "'"));
-    }
-
-    private static Predicate<Named> named(String name) {
-        return named -> named.getName().equals(name);
-    }
-
 }
diff --git a/variants/src/main/java/org/implab/gradle/variants/VariantsPlugin.java b/variants/src/main/java/org/implab/gradle/variants/VariantsPlugin.java
--- a/variants/src/main/java/org/implab/gradle/variants/VariantsPlugin.java
+++ b/variants/src/main/java/org/implab/gradle/variants/VariantsPlugin.java
@@ -23,13 +23,15 @@ import org.implab.gradle.variants.intern
  *
  */
 public abstract class VariantsPlugin implements Plugin<Project> {
+    public static final String VARIANTS_EXTENSION = "variants";
+
     @Override
     public void apply(Project target) {
 
         var objectFactory = target.getObjects();
 
         var variantsExtension = new DefaultVariantsExtension(objectFactory);
-        target.getExtensions().add(VariantsExtension.class, "variants", variantsExtension);
+        target.getExtensions().add(VariantsExtension.class, VARIANTS_EXTENSION, variantsExtension);
         target.afterEvaluate(t -> variantsExtension.finalizeExtension());
 
     }
diff --git a/variants/src/main/java/org/implab/gradle/variants/sources/GenericSourceSet.java b/variants/src/main/java/org/implab/gradle/variants/sources/GenericSourceSet.java
--- a/variants/src/main/java/org/implab/gradle/variants/sources/GenericSourceSet.java
+++ b/variants/src/main/java/org/implab/gradle/variants/sources/GenericSourceSet.java
@@ -1,7 +1,6 @@
 package org.implab.gradle.variants.sources;
 
 import java.io.File;
-import java.nio.file.Paths;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -22,7 +21,6 @@ import org.gradle.api.Task;
 import org.gradle.api.file.ConfigurableFileCollection;
 import org.gradle.api.file.DirectoryProperty;
 import org.gradle.api.file.FileCollection;
-import org.gradle.api.file.ProjectLayout;
 import org.gradle.api.file.SourceDirectorySet;
 import org.gradle.api.model.ObjectFactory;
 import org.gradle.api.tasks.TaskProvider;
@@ -33,9 +31,10 @@ import org.gradle.api.tasks.TaskProvider
  * <p>
  * Each instance aggregates multiple {@link SourceDirectorySet source sets}
  * under a shared name and exposes typed outputs that must be declared up front.
- * Default locations are {@code src/<name>} for sources and
- * {@code build/<name>} for outputs, both of which can be customized via the
- * exposed {@link DirectoryProperty} setters.
+ * Source and output base directories are explicit model properties. They do
+ * not define source directories or outputs by themselves; plugins and adapters
+ * may attach conventions or use them as layout hints for their own
+ * materialization rules.
  * </p>
  *
  * <p>
@@ -62,7 +61,7 @@ public abstract class GenericSourceSet i
     private final Set<String> declaredOutputs = new HashSet<>();
 
     @Inject
-    public GenericSourceSet(String name, ObjectFactory objects, ProjectLayout layout) {
+    public GenericSourceSet(String name, ObjectFactory objects) {
         this.name = name;
         this.objects = objects;
 
@@ -75,14 +74,6 @@ public abstract class GenericSourceSet i
         allSourceDirectories = objects.fileCollection().from(sourceDirectoriesProvider());
 
         allOutputs = objects.fileCollection().from(outputsProvider());
-
-        getSourceSetDir().convention(layout
-                .getProjectDirectory()
-                .dir(Paths.get("src", name).toString()));
-
-        getOutputsDir().convention(layout
-                .getBuildDirectory()
-                .dir(name));
     }
 
     @Override
@@ -91,14 +82,24 @@ public abstract class GenericSourceSet i
     }
 
     /**
-     * Base directory for this source set. Defaults to {@code src/<name>} under
-     * the project directory.
+     * Base directory associated with this source set.
+     *
+     * <p>
+     * This property is intentionally convention-free in the base model. A
+     * plugin may attach a convention when it knows the surrounding layout
+     * policy, for example when materializing variant compile units.
+     * </p>
      */
     public abstract DirectoryProperty getSourceSetDir();
 
     /**
-     * Base directory for outputs of this source set. Defaults to
-     * {@code build/<name>}.
+     * Base directory associated with outputs of this source set.
+     *
+     * <p>
+     * This property is a layout hint. Actual named outputs are declared and
+     * populated through {@link #declareOutputs(String, String...)} and
+     * {@link #registerOutput(String, Object...)}.
+     * </p>
      */
     public abstract DirectoryProperty getOutputsDir();
 
diff --git a/variants/src/main/java/org/implab/gradle/variants/sources/internal/CompileUnitLayoutConvention.java b/variants/src/main/java/org/implab/gradle/variants/sources/internal/CompileUnitLayoutConvention.java
new file mode 100644
--- /dev/null
+++ b/variants/src/main/java/org/implab/gradle/variants/sources/internal/CompileUnitLayoutConvention.java
@@ -0,0 +1,45 @@
+package org.implab.gradle.variants.sources.internal;
+
+import org.gradle.api.Action;
+import org.gradle.api.file.Directory;
+import org.gradle.api.provider.Provider;
+import org.implab.gradle.common.core.lang.FilePaths;
+import org.implab.gradle.variants.sources.CompileUnitSourceSetSpec;
+
+/**
+ * Applies the default layout policy for source sets materialized from variant
+ * compile units.
+ *
+ * <p>
+ * The convention keeps sources grouped by layer and outputs grouped by
+ * variant/layer. It only sets directory properties on the materialized source
+ * set; declaring source directories and named outputs remains the
+ * responsibility of adapters or user DSL.
+ * </p>
+ */
+public class CompileUnitLayoutConvention implements Action<CompileUnitSourceSetSpec> {
+    private final Provider<Directory> sourcesBaseDir;
+    private final Provider<Directory> outputsBaseDir;
+
+    public CompileUnitLayoutConvention(
+            Provider<Directory> baseDirectory,
+            Provider<Directory> outputsBaseDir) {
+        this.sourcesBaseDir = baseDirectory;
+        this.outputsBaseDir = outputsBaseDir;
+    }
+
+    @Override
+    public void execute(CompileUnitSourceSetSpec spec) {
+        var sourceSet = spec.getSourceSet();
+        var unit = spec.getCompileUnit();
+        var layerName = unit.layer().getName();
+        var variantName = unit.variant().getName();
+
+        sourceSet.getSourceSetDir()
+                .convention(sourcesBaseDir.map(base -> base.dir(FilePaths.cat(layerName))));
+
+        sourceSet.getOutputsDir()
+                .convention(outputsBaseDir.map(base -> base.dir(FilePaths.cat(variantName, layerName))));
+    }
+
+}
diff --git a/variants/src/test/java/org/implab/gradle/variants/PluginMarkerFunctionalTest.java b/variants/src/test/java/org/implab/gradle/variants/PluginMarkerFunctionalTest.java
--- a/variants/src/test/java/org/implab/gradle/variants/PluginMarkerFunctionalTest.java
+++ b/variants/src/test/java/org/implab/gradle/variants/PluginMarkerFunctionalTest.java
@@ -63,6 +63,8 @@ class PluginMarkerFunctionalTest extends
                     doLast {
                         def main = sources.named('main').get()
                         println("sourceSet=" + main.name)
+                        println("sourceSetDir=" + project.relativePath(main.sourceSetDir.get().asFile))
+                        println("outputsDir=" + project.relativePath(main.outputsDir.get().asFile))
                         println("jsFiles=" + main.output('js').files.collect { it.name }.sort().join(','))
                     }
                 }
@@ -71,6 +73,8 @@ class PluginMarkerFunctionalTest extends
         BuildResult result = runner("probe").build();
 
         assertTrue(result.getOutput().contains("sourceSet=main"));
+        assertTrue(result.getOutput().contains("sourceSetDir=src/main"));
+        assertTrue(result.getOutput().contains("outputsDir=build/out/main"));
         assertTrue(result.getOutput().contains("jsFiles=main.js"));
     }
 
diff --git a/variants/src/test/java/org/implab/gradle/variants/VariantSourcesPluginFunctionalTest.java b/variants/src/test/java/org/implab/gradle/variants/VariantSourcesPluginFunctionalTest.java
--- a/variants/src/test/java/org/implab/gradle/variants/VariantSourcesPluginFunctionalTest.java
+++ b/variants/src/test/java/org/implab/gradle/variants/VariantSourcesPluginFunctionalTest.java
@@ -40,12 +40,15 @@ class VariantSourcesPluginFunctionalTest
 
                     def left = ctx.sourceSets.getSourceSet(unit)
                     def right = ctx.sourceSets.getSourceSet(unit)
+                    def sourceSet = left.get()
 
                     lines << "projectionUnits=" + ctx.roleProjections.getUnits(projection)
                         .collect { it.layer().name }
                         .sort()
                         .join(',')
-                    lines << "mainSourceSet=" + left.name
+                    lines << "mainSourceSet=" + sourceSet.name
+                    lines << "mainSourceSetDir=" + project.relativePath(sourceSet.sourceSetDir.get().asFile)
+                    lines << "mainOutputsDir=" + project.relativePath(sourceSet.outputsDir.get().asFile)
                     lines << "sameProvider=" + left.is(right)
                 }
 
@@ -67,6 +70,8 @@ class VariantSourcesPluginFunctionalTest
         assertTrue(result.getOutput().contains("units=browser:main,browser:test"));
         assertTrue(result.getOutput().contains("projectionUnits=main"));
         assertTrue(result.getOutput().contains("mainSourceSet=browserMain"));
+        assertTrue(result.getOutput().contains("mainSourceSetDir=src/main"));
+        assertTrue(result.getOutput().contains("mainOutputsDir=build/variants/browser/main"));
         assertTrue(result.getOutput().contains("sameProvider=true"));
         assertTrue(result.getOutput().contains("late:variants=browser"));
     }
@@ -372,7 +377,7 @@ class VariantSourcesPluginFunctionalTest
                 }
                 """);
 
-        assertBuildFails("Variant 'missing' isn't declared", "help");
+        assertBuildFails("The specified variant 'missing' isn't declared", "help");
     }
 
     @Test
@@ -423,7 +428,7 @@ class VariantSourcesPluginFunctionalTest
                 }
                 """);
 
-        assertBuildFails("Layer 'missing' isn't declared", "help");
+        assertBuildFails("The specified layer 'missing' isn't declared", "help");
     }
 
     @Test
@@ -475,7 +480,7 @@ class VariantSourcesPluginFunctionalTest
                 }
                 """);
 
-        assertBuildFails("The CompileUnit isn't declared for variant 'browser', layer 'test'", "help");
+        assertBuildFails("Compile unit for variant 'browser' and layer 'test' not found", "help");
     }
 
     @Test