ModuleOrigin -> ModuleIdentifier

libraries/tools/kotlin-project-model/src/main/kotlin/DependencyResolution.kt

@@ -5,10 +5,15 @@
 
 package org.jetbrains.kotlin.project.model
 
+// TODO ensure that resolvers are pluggable + custom dependency kinds (& result kinds?)
+// TODO think about state management: unresolved -> (known dependency graph?) ... -> completely resolved
+//      it seems to be important to learn whether or not the model is final
 interface ModuleDependencyResolver {
     fun resolveDependency(moduleDependency: ModuleDependency): KotlinModule?
 }
 
+// TODO merge with ModuleDependencyResolver?
+//  Semantically, they are close and may use shared caches and other shared state in the implementations
 interface DependencyDiscovery {
     // TODO return dependency graph rather than just iterable?
     // TODO make this a partial function, too

libraries/tools/kotlin-project-model/src/main/kotlin/KotlinModule.kt

@@ -5,13 +5,26 @@
 
 package org.jetbrains.kotlin.project.model
 
-sealed class ModuleOrigin
-data class LocalBuild(val buildId: String) : ModuleOrigin() // TODO add project ID?
-data class ExternalOrigin(val dependencyIdParts: List<String>) : ModuleOrigin()
+// TODO sealed with an abstract subclass? this will make exhaustive checks work
+open class ModuleIdentifier
+
+// TODO consider id: Any, to allow IDs with custom equality?
+data class LocalModuleIdentifier(val buildId: String, val projectId: String) : ModuleIdentifier() {
+    companion object {
+        private const val SINGLE_BUILD_ID = ":"
+    }
+
+    override fun toString(): String = "project '$projectId'" + buildId.takeIf { it != SINGLE_BUILD_ID }?.let { "(build '$it')" }.orEmpty()
+}
+
+data class MavenModuleIdentifier(val group: String, val name: String) : ModuleIdentifier() {
+    override fun toString(): String = "$group:$name"
+}
+
+// TODO Gradle allows having multiple capabilities in a published module, we need to figure out how we can include them in the module IDs
 
 interface KotlinModule {
-    val moduleName: String
-    val moduleOrigin: ModuleOrigin
+    val moduleIdentifier: ModuleIdentifier
 
     val fragments: Iterable<KotlinModuleFragment>
 
@@ -20,10 +33,9 @@ interface KotlinModule {
 }
 
 class BasicKotlinModule(
-    override val moduleName: String,
-    override val moduleOrigin: ModuleOrigin
+    override val moduleIdentifier: ModuleIdentifier
 ) : KotlinModule {
     override val fragments = mutableListOf<BasicKotlinModuleFragment>()
 
-    override fun toString(): String = "module '$moduleName'"
+    override fun toString(): String = "module $moduleIdentifier"
 }

libraries/tools/kotlin-project-model/src/main/kotlin/ModuleDependency.kt

@@ -5,13 +5,11 @@
 
 package org.jetbrains.kotlin.project.model
 
-sealed class ModuleDependency(open val moduleOrigin: ModuleOrigin)
-
-data class ExternalModuleDependency(override val moduleOrigin: ExternalOrigin) : ModuleDependency(moduleOrigin) {
-    override fun toString() = "external dependency ${moduleOrigin.dependencyIdParts.joinToString(":")}"
+data class ModuleDependency(val moduleIdentifier: ModuleIdentifier) {
+    override fun toString(): String = "dependency $moduleIdentifier"
 }
 
-data class LocalModuleDependency(override val moduleOrigin: LocalBuild, val moduleName: String) :
-    ModuleDependency(moduleOrigin) {
-    override fun toString() = "local module $moduleName (build ${moduleOrigin.buildId})"
-}
+/**
+ * TODO other kinds of dependencies: non-Kotlin: cinterop, CocoaPods, NPM dependencies?
+ *  support with different moduleIdentifiers? Introduce other kinds of dependencies than ModuleDependency?
+ */

libraries/tools/kotlin-project-model/src/test/kotlin/org/jetbrains/kotlin/project/model/SimpleModel.kt

@@ -5,7 +5,7 @@
 
 package org.jetbrains.kotlin.project.model
 
-fun module(name: String) = BasicKotlinModule(name, LocalBuild("current"))
+fun module(name: String) = BasicKotlinModule(LocalModuleIdentifier("current", name))
 
 fun BasicKotlinModule.fragment(vararg nameParts: String): BasicKotlinModuleFragment =
     fragment(nameParts.drop(1).joinToString("", nameParts.first()) { it.capitalize() })