Make remapped configurations lazy

src/main/java/net/fabricmc/loom/LoomGradleExtension.java

@@ -48,6 +48,7 @@ import org.jetbrains.annotations.ApiStatus;
 
 import net.fabricmc.loom.api.decompilers.LoomDecompiler;
 import net.fabricmc.loom.configuration.LoomDependencyManager;
+import net.fabricmc.loom.configuration.LoomProjectData;
 import net.fabricmc.loom.configuration.ide.RunConfigSettings;
 import net.fabricmc.loom.configuration.processors.JarProcessor;
 import net.fabricmc.loom.configuration.processors.JarProcessorManager;
@@ -80,6 +81,9 @@ public class LoomGradleExtension {
 	private Mercury[] srcMercuryCache = new Mercury[2];
 	private Set<File> mixinMappings = Collections.synchronizedSet(new HashSet<>());
 
+	@ApiStatus.Internal
+	private final LoomProjectData projectData;
+
 	private NamedDomainObjectContainer<RunConfigSettings> runConfigs;
 
 	/**
@@ -119,6 +123,7 @@ public class LoomGradleExtension {
 		this.runConfigs = project.container(RunConfigSettings.class,
 				baseName -> new RunConfigSettings(project, baseName));
 		this.log4jConfigs = project.files(getDefaultLog4jConfigFile());
+		projectData = new LoomProjectData(project);
 	}
 
 	/**
@@ -371,4 +376,9 @@ public class LoomGradleExtension {
 	public NamedDomainObjectContainer<RunConfigSettings> getRunConfigs() {
 		return runConfigs;
 	}
+
+	@ApiStatus.Internal
+	public LoomProjectData getProjectData() {
+		return projectData;
+	}
 }

src/main/java/net/fabricmc/loom/build/ModCompileRemapper.java

@@ -46,6 +46,7 @@ import org.gradle.language.base.artifact.SourcesArtifact;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.LoomGradlePlugin;
+import net.fabricmc.loom.configuration.LoomProjectData;
 import net.fabricmc.loom.configuration.RemappedConfigurationEntry;
 import net.fabricmc.loom.configuration.mods.ModProcessor;
 import net.fabricmc.loom.configuration.processors.dependency.ModDependencyInfo;
@@ -64,9 +65,11 @@ public class ModCompileRemapper {
 		final File modStore = extension.getRemappedModCache();
 		final RemapData remapData = new RemapData(mappingsSuffix, modStore);
 
+		final LoomProjectData data = extension.getProjectData();
+
 		for (RemappedConfigurationEntry entry : Constants.MOD_COMPILE_ENTRIES) {
+			data.getLazyConfigurationProvider(entry.getRemappedConfiguration()).configure(remappedConfig -> {
 				Configuration sourceConfig = project.getConfigurations().getByName(entry.getSourceConfiguration());
-			Configuration remappedConfig = project.getConfigurations().getByName(entry.getRemappedConfiguration());
 				Configuration regularConfig = project.getConfigurations().getByName(entry.getTargetConfiguration(project.getConfigurations()));
 
 				List<ModDependencyInfo> modDependencies = new ArrayList<>();
@@ -118,6 +121,7 @@ public class ModCompileRemapper {
 				for (ModDependencyInfo info : modDependencies) {
 					project.getDependencies().add(info.targetConfig.getName(), info.getRemappedNotation());
 				}
+			});
 		}
 	}
 

src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java

@@ -72,11 +72,15 @@ public final class CompileConfiguration {
 		project.getConfigurations().maybeCreate(Constants.Configurations.LOOM_DEVELOPMENT_DEPENDENCIES);
 		project.getConfigurations().maybeCreate(Constants.Configurations.UNPICK_CLASSPATH);
 
+		LoomProjectData data = project.getExtensions().getByType(LoomGradleExtension.class).getProjectData();
+
 		for (RemappedConfigurationEntry entry : Constants.MOD_COMPILE_ENTRIES) {
-			Configuration compileModsConfig = project.getConfigurations().maybeCreate(entry.getSourceConfiguration());
-			compileModsConfig.setTransitive(true);
-			Configuration compileModsMappedConfig = project.getConfigurations().maybeCreate(entry.getRemappedConfiguration());
-			compileModsMappedConfig.setTransitive(false); // Don't get transitive deps of already remapped mods
+			data.createLazyConfiguration(entry.getSourceConfiguration())
+					.configure(configuration -> configuration.setTransitive(true));
+
+			// Don't get transitive deps of already remapped mods
+			data.createLazyConfiguration(entry.getRemappedConfiguration())
+					.configure(configuration -> configuration.setTransitive(false));
 
 			extendsFrom(entry.getTargetConfiguration(project.getConfigurations()), entry.getRemappedConfiguration(), project);
 

src/main/java/net/fabricmc/loom/configuration/LoomProjectData.java

@@ -0,0 +1,70 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2016, 2017, 2018 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+
+import org.gradle.api.NamedDomainObjectProvider;
+import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
+import org.jetbrains.annotations.ApiStatus;
+
+@ApiStatus.Internal
+/**
+ * This class is stored in the gradle extension, and should not be used outside of loom.
+ * It contains data/info related to the current project
+ */
+public final class LoomProjectData {
+	private final Project project;
+	private final Map<String, NamedDomainObjectProvider<Configuration>> lazyConfigurations = new HashMap<>();
+
+	public LoomProjectData(Project project) {
+		this.project = Objects.requireNonNull(project);
+	}
+
+	public NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name) {
+		NamedDomainObjectProvider<Configuration> provider = project.getConfigurations().register(name);
+
+		if (lazyConfigurations.containsKey(name)) {
+			throw new IllegalStateException("Duplicate configuration name" + name);
+		}
+
+		lazyConfigurations.put(name, provider);
+
+		return provider;
+	}
+
+	public NamedDomainObjectProvider<Configuration> getLazyConfigurationProvider(String name) {
+		NamedDomainObjectProvider<Configuration> provider = lazyConfigurations.get(name);
+
+		if (provider == null) {
+			throw new NullPointerException("Could not find provider with name: " + name);
+		}
+
+		return provider;
+	}
+}