Gradle, js: extract NpmProjectModules to separate file

#KT-30530

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/NpmProject.kt

@@ -5,8 +5,6 @@
 
 package org.jetbrains.kotlin.gradle.targets.js.npm
 
-import com.google.gson.Gson
-import com.google.gson.JsonObject
 import org.gradle.api.Project
 import org.gradle.process.ExecSpec
 import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsPlugin
@@ -28,14 +26,13 @@ open class NpmProject(
     open val compileOutputCopyDest: File?
         get() = nodeModulesDir
 
-    fun useTool(exec: ExecSpec, tool: String, vararg args: String) {
+    private val modules = object : NpmProjectModules(nodeWorkDir, nodeModulesDir) {
-        NpmResolver.resolve(project)
+        override val parent get() = if (searchInParents) parentModules else null
-
-        exec.workingDir = nodeWorkDir
-        exec.executable = project.nodeJs.root.environment.nodeExecutable
-        exec.args = listOf(require(tool)) + args
     }
 
+    private val parentModules: NpmProjectModules?
+        get() = project.parent?.npmProject?.modules
+
     val hoistGradleNodeModules: Boolean
         get() = project.nodeJs.root.packageManager.shouldHoistGradleNodeModules(project)
 
@@ -48,68 +45,25 @@ open class NpmProject(
         return compileOutputCopyDest?.resolve(compilationTask.outputFile.name) ?: compilationTask.outputFile
     }
 
+    fun useTool(exec: ExecSpec, tool: String, vararg args: String) {
+        exec.workingDir = nodeWorkDir
+        exec.executable = project.nodeJs.root.environment.nodeExecutable
+        exec.args = listOf(require(tool)) + args
+    }
+
     /**
      * Require [request] nodejs module and return canonical path to it's main js file.
      */
     fun require(request: String): String {
         NpmResolver.requireResolved(project)
-        return resolve(request)?.canonicalPath ?: error("Cannot find node module \"$request\" in \"$this\"")
+        return modules.require(request)
     }
 
     /**
      * Find node module according to https://nodejs.org/api/modules.html#modules_all_together,
      * with exception that instead of traversing parent folders, we are traversing parent projects
      */
-    internal fun resolve(name: String, context: File = nodeWorkDir): File? =
+    internal fun resolve(name: String): File? = modules.resolve(name)
-        if (name.startsWith("/")) resolve(name.removePrefix("/"), File("/"))
-        else resolveAsRelative("./", name, context)
-            ?: resolveAsRelative("/", name, context)
-            ?: resolveAsRelative("../", name, context)
-            ?: resolveInNodeModulesDir(name, nodeModulesDir)
-            ?: if (searchInParents) project.parent?.let { NpmProject[it].resolve(name) } else null
-
-    private fun resolveAsRelative(prefix: String, name: String, context: File): File? {
-        if (!name.startsWith(prefix)) return null
-
-        val relative = context.resolve(name.removePrefix(prefix))
-        return resolveAsFile(relative)
-            ?: resolveAsDirectory(relative)
-    }
-
-    private fun resolveInNodeModulesDir(name: String, nodeModulesDir: File): File? {
-        return resolveAsFile(nodeModulesDir.resolve(name))
-            ?: resolveAsDirectory(nodeModulesDir.resolve(name))
-    }
-
-    private fun resolveAsDirectory(dir: File): File? {
-        val packageJsonFile = dir.resolve("package.json")
-        val main: String? = if (packageJsonFile.isFile) {
-            val packageJson = packageJsonFile.reader().use {
-                Gson().fromJson(it, JsonObject::class.java)
-            }
-
-            packageJson["main"] as? String?
-                ?: packageJson["module"] as? String?
-                ?: packageJson["browser"] as? String?
-        } else null
-
-        return if (main != null) {
-            val mainFile = dir.resolve(main)
-            resolveAsFile(mainFile)
-                ?: resolveIndex(mainFile)
-        } else resolveIndex(dir)
-    }
-
-    private fun resolveIndex(dir: File): File? = resolveAsFile(dir.resolve("index"))
-
-    private fun resolveAsFile(file: File): File? {
-        if (file.isFile) return file
-
-        val js = File(file.path + ".js")
-        if (js.isFile) return js
-
-        return null
-    }
 
     override fun toString() = "NpmProject($nodeWorkDir)"
 

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/NpmProjectModules.kt

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.targets.js.npm
+
+import com.google.gson.Gson
+import com.google.gson.JsonObject
+import org.jetbrains.kotlin.gradle.targets.js.npm.NpmProject.Companion.NODE_MODULES
+import org.jetbrains.kotlin.gradle.targets.js.npm.NpmProject.Companion.PACKAGE_JSON
+import java.io.File
+
+internal open class NpmProjectModules(
+    val dir: File,
+    val nodeModulesDir: File = dir.resolve(NODE_MODULES)
+) {
+    /**
+     * Require [request] nodejs module and return canonical path to it's main js file.
+     */
+    fun require(request: String): String {
+        return resolve(request)?.canonicalPath ?: error("Cannot find node module \"$request\" in \"$this\"")
+    }
+
+    open val parent: NpmProjectModules?
+        get() = null
+
+    /**
+     * Find node module according to https://nodejs.org/api/modules.html#modules_all_together,
+     * with exception that instead of traversing parent folders, we are traversing parent projects
+     */
+    internal fun resolve(name: String, context: File = dir): File? =
+        if (name.startsWith("/")) resolve(name.removePrefix("/"), File("/"))
+        else resolveAsRelative("./", name, context)
+            ?: resolveAsRelative("/", name, context)
+            ?: resolveAsRelative("../", name, context)
+            ?: resolveInNodeModulesDir(name, nodeModulesDir)
+            ?: parent?.resolve(name)
+
+    private fun resolveAsRelative(prefix: String, name: String, context: File): File? {
+        if (!name.startsWith(prefix)) return null
+
+        val relative = context.resolve(name.removePrefix(prefix))
+        return resolveAsFile(relative)
+            ?: resolveAsDirectory(relative)
+    }
+
+    private fun resolveInNodeModulesDir(name: String, nodeModulesDir: File): File? {
+        return resolveAsFile(nodeModulesDir.resolve(name))
+            ?: resolveAsDirectory(nodeModulesDir.resolve(name))
+    }
+
+    private fun resolveAsDirectory(dir: File): File? {
+        val packageJsonFile = dir.resolve(PACKAGE_JSON)
+        val main: String? = if (packageJsonFile.isFile) {
+            val packageJson = packageJsonFile.reader().use {
+                Gson().fromJson(it, JsonObject::class.java)
+            }
+
+            packageJson["main"] as? String?
+                ?: packageJson["module"] as? String?
+                ?: packageJson["browser"] as? String?
+        } else null
+
+        return if (main != null) {
+            val mainFile = dir.resolve(main)
+            resolveAsFile(mainFile)
+                ?: resolveIndex(mainFile)
+        } else resolveIndex(dir)
+    }
+
+    private fun resolveIndex(dir: File): File? = resolveAsFile(dir.resolve(INDEX_FILE_NAME))
+
+    private fun resolveAsFile(file: File): File? {
+        if (file.isFile) return file
+
+        val js = File(file.path + JS_SUFFIX)
+        if (js.isFile) return js
+
+        return null
+    }
+
+    companion object {
+        const val JS_SUFFIX = ".js"
+        const val INDEX_FILE_NAME = "index"
+    }
+}