From c28d8c6575b14245db220f02e5a660b5ed1c4f9c Mon Sep 17 00:00:00 2001
From: Sergey Igushkin <sergey.igushkin@jetbrains.com>
Date: Mon, 10 Feb 2020 14:59:11 +0300
Subject: [PATCH] Don't iterate over all tasks in KotlinProjectNpmResolver
 (KT-36472)

Iterating over all tasks triggered the tasks to configure even if that
was not necessary. Filter the task collection by type instead.

Issue #KT-36472 Fixed
---
 .../npm/resolver/KotlinProjectNpmResolver.kt  | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/resolver/KotlinProjectNpmResolver.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/resolver/KotlinProjectNpmResolver.kt
index a93576246ca..b5bf6822097 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/resolver/KotlinProjectNpmResolver.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/resolver/KotlinProjectNpmResolver.kt
@@ -6,6 +6,8 @@
 package org.jetbrains.kotlin.gradle.targets.js.npm.resolver
 
 import org.gradle.api.Project
+import org.gradle.api.Task
+import org.gradle.api.tasks.TaskCollection
 import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
 import org.jetbrains.kotlin.gradle.dsl.KotlinSingleTargetExtension
 import org.jetbrains.kotlin.gradle.dsl.kotlinExtensionOrNull
@@ -16,6 +18,7 @@ import org.jetbrains.kotlin.gradle.targets.js.KotlinJsTarget
 import org.jetbrains.kotlin.gradle.targets.js.RequiredKotlinJsDependency
 import org.jetbrains.kotlin.gradle.targets.js.npm.RequiresNpmDependencies
 import org.jetbrains.kotlin.gradle.targets.js.npm.resolved.KotlinProjectNpmResolution
+import kotlin.reflect.KClass
 
 /**
  * See [KotlinNpmResolutionManager] for details about resolution process.
@@ -112,9 +115,9 @@ internal class KotlinProjectNpmResolver(
             private set
 
         init {
-            projectNpmResolver.project.tasks.forEach { task ->
-                if (task.enabled && task is RequiresNpmDependencies) {
-                    addTaskRequirements(task)
+            projectNpmResolver.project.tasks.implementing(RequiresNpmDependencies::class).forEach { task ->
+                if (task.enabled) {
+                    addTaskRequirements(task as RequiresNpmDependencies)
                     task.dependsOn(projectNpmResolver[task.compilation].packageJsonTaskHolder)
                     task.dependsOn(projectNpmResolver.resolver.nodeJs.npmInstallTask)
                 }
@@ -135,4 +138,13 @@ internal class KotlinProjectNpmResolver(
                 .add(task)
         }
     }
-}
\ No newline at end of file
+}
+
+/**
+ * Filters a [TaskCollection] by type that is not a subtype of [Task] (for use with interfaces)
+ *
+ * TODO properly express within the type system? The result should be a TaskCollection<T & R>
+ */
+private fun <T : Task, R : Any> TaskCollection<T>.implementing(kclass: KClass<R>): TaskCollection<T> =
+    @Suppress("UNCHECKED_CAST")
+    withType(kclass.java as Class<T>)
\ No newline at end of file