Configure imperatively

src/main/java/net/neoforged/moddevgradle/dsl/ImmutableModdingVersions.java

@@ -0,0 +1,6 @@
+package net.neoforged.moddevgradle.dsl;
+
+import groovyjarjarantlr4.v4.runtime.misc.Nullable;
+
+public record ImmutableModdingVersions(@Nullable String neoForgeVersion, @Nullable String neoFormVersion) {
+}

src/main/java/net/neoforged/moddevgradle/dsl/ModdingVersionSettings.java

@@ -0,0 +1,41 @@
+package net.neoforged.moddevgradle.dsl;
+
+import org.gradle.api.provider.ListProperty;
+import org.gradle.api.tasks.SourceSet;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.Nullable;
+
+public abstract class ModdingVersionSettings {
+    @Nullable
+    private String neoForgeVersion;
+
+    @Nullable
+    private String neoFormVersion;
+
+    /**
+     * NeoForge version number. You have to set either this or {@link #setNeoFormVersion}.
+     */
+    public void setNeoForgeVersion(String version) {
+        this.neoForgeVersion = version;
+    }
+
+    /**
+     * You can set this property to a version of <a href="https://projects.neoforged.net/neoforged/neoform">NeoForm</a>
+     * to either override the version used in the version of NeoForge you set, or to compile against
+     * Vanilla artifacts that have no NeoForge code added.
+     */
+    public void setNeoFormVersion(String version) {
+        this.neoFormVersion = version;
+    }
+
+    /**
+     * Contains the list of source sets for which access to Minecraft classes should be configured.
+     * Defaults to the main source set, but can also be set to an empty list.
+     */
+    public abstract ListProperty<SourceSet> getEnabledSourceSets();
+
+    @ApiStatus.Internal
+    public ImmutableModdingVersions toImmutable() {
+        return new ImmutableModdingVersions(neoForgeVersion, neoFormVersion);
+    }
+}

src/main/java/net/neoforged/moddevgradle/dsl/NeoForgeExtension.java

@@ -3,7 +3,7 @@
 import net.neoforged.moddevgradle.internal.ModDevPlugin;
 import net.neoforged.moddevgradle.internal.utils.ExtensionUtils;
 import org.gradle.api.Action;
-import org.gradle.api.GradleException;
+import org.gradle.api.InvalidUserCodeException;
 import org.gradle.api.NamedDomainObjectContainer;
 import org.gradle.api.Project;
 import org.gradle.api.Task;
@@ -15,6 +15,7 @@
 
 import javax.inject.Inject;
 import java.io.File;
+import java.util.List;
 
 /**
  * This is the top-level {@code neoForge} extension, used to configure the moddev plugin.
@@ -44,34 +45,31 @@ public NeoForgeExtension(Project project, DataFileCollection accessTransformers,
         unitTest.getLoadedMods().convention(getMods());
     }
 
-    /**
-     * Adds the necessary dependencies to develop a Minecraft mod to the given source set.
-     * The plugin automatically adds these dependencies to the main source set.
-     */
-    public void addModdingDependenciesTo(SourceSet sourceSet) {
-        var configurations = project.getConfigurations();
-        var sourceSets = ExtensionUtils.getSourceSets(project);
-        if (!sourceSets.contains(sourceSet)) {
-            throw new GradleException("Cannot add to the source set in another project.");
-        }
-
-        configurations.getByName(sourceSet.getRuntimeClasspathConfigurationName())
-                .extendsFrom(configurations.getByName(ModDevPlugin.CONFIGURATION_RUNTIME_DEPENDENCIES));
-        configurations.getByName(sourceSet.getCompileClasspathConfigurationName())
-                .extendsFrom(configurations.getByName(ModDevPlugin.CONFIGURATION_COMPILE_DEPENDENCIES));
+    @Deprecated(forRemoval = true)
+    public void setVersion(Object any) {
+        throw new InvalidUserCodeException("Please use enableModding { neoForgeVersion = ... } instead of the version property.");
     }
 
-    /**
-     * NeoForge version number. You have to set either this or {@link #getNeoFormVersion()}.
-     */
-    public abstract Property<String> getVersion();
+    public void enableModding(Action<ModdingVersionSettings> customizer) {
+        var modDevPlugin = project.getPlugins().getPlugin(ModDevPlugin.class);
 
-    /**
-     * You can set this property to a version of <a href="https://projects.neoforged.net/neoforged/neoform">NeoForm</a>
-     * to either override the version used in the version of NeoForge you set, or to compile against
-     * Vanilla artifacts that have no NeoForge code added.
-     */
-    public abstract Property<String> getNeoFormVersion();
+        var settings = project.getObjects().newInstance(ModdingVersionSettings.class);
+        // By default enable modding deps only for the main source set
+        settings.getEnabledSourceSets().convention(project.provider(() -> {
+            var sourceSets = ExtensionUtils.getSourceSets(project);
+            return List.of(sourceSets.getByName(SourceSet.MAIN_SOURCE_SET_NAME));
+        }));
+        customizer.execute(settings);
+
+        var versions = settings.toImmutable();
+
+        modDevPlugin.enableModding(
+                project,
+                settings.getEnabledSourceSets().get(),
+                versions.neoForgeVersion(),
+                versions.neoFormVersion()
+        );
+    }
 
     /**
      * The list of additional access transformers that should be applied to the Minecraft source code.