Add test on essential plugins

All dependencies of essential plugin should be added as essential plugins otherwise on disabling any of them the product can't be loaded

GitOrigin-RevId: 1ce336e294b07d3672cdbb9279e3dabca947f48c

build/tests/testSrc/org/jetbrains/intellij/build/IdeaCommunityBuildTest.kt

@@ -3,6 +3,7 @@ package org.jetbrains.intellij.build
 
 import com.intellij.openapi.application.PathManager
 import com.intellij.platform.buildScripts.testFramework.createBuildOptionsForTest
+import com.intellij.platform.buildScripts.testFramework.runEssentialPluginsTest
 import com.intellij.platform.buildScripts.testFramework.runTestBuild
 import com.intellij.platform.buildScripts.testFramework.spanName
 import kotlinx.coroutines.Dispatchers
@@ -43,4 +44,12 @@ class IdeaCommunityBuildTest {
       }
     }
   }
+
+  @Test
+  fun `essential plugins depend only on essential plugins`() {
+    val homePath = PathManager.getHomeDirFor(javaClass)!!
+    runEssentialPluginsTest(homePath = homePath,
+                            productProperties = IdeaCommunityProperties(COMMUNITY_ROOT.communityRoot),
+                            buildTools = ProprietaryBuildTools.DUMMY)
+  }
 }

platform/build-scripts/testFramework/intellij.platform.buildScripts.testFramework.iml

@@ -31,5 +31,6 @@
     <orderEntry type="module" module-name="intellij.platform.jps.build" />
     <orderEntry type="module" module-name="intellij.platform.runtime.product" />
     <orderEntry type="library" name="devkit.runtime.module.repository.jps" level="project" />
+    <orderEntry type="module" module-name="intellij.platform.util.xmlDom" />
   </component>
 </module>

platform/build-scripts/testFramework/src/com/intellij/platform/buildScripts/testFramework/EssentialPluginsTestBase.kt

@@ -0,0 +1,61 @@
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.platform.buildScripts.testFramework
+
+import com.intellij.util.xml.dom.readXmlAsModel
+import kotlinx.coroutines.runBlocking
+import org.assertj.core.api.SoftAssertions
+import org.jetbrains.intellij.build.BuildContext
+import org.jetbrains.intellij.build.ProductProperties
+import org.jetbrains.intellij.build.ProprietaryBuildTools
+import org.jetbrains.intellij.build.impl.BuildContextImpl
+import org.jetbrains.intellij.build.impl.collectPluginDescriptors
+import java.nio.file.Path
+
+fun runEssentialPluginsTest(
+  homePath: Path,
+  productProperties: ProductProperties,
+  buildTools: ProprietaryBuildTools,
+) = runBlocking {
+  val buildContext = BuildContextImpl.createContext(
+    projectHome = homePath,
+    productProperties = productProperties,
+    proprietaryBuildTools = buildTools,
+    setupTracer = false,
+    options = createBuildOptionsForTest(productProperties = productProperties, homeDir = homePath)
+  )
+  val essentialPlugins = readXmlAsModel(buildContext.appInfoXml.toByteArray()).children.filter { it.name == "essential-plugin" }.mapNotNull { it.content }
+  val softly = SoftAssertions()
+  println("Essential plugins: ${essentialPlugins.joinToString(", ")}")
+  val pluginById = getPluginByIdMap(buildContext)
+  for (essentialPlugin in essentialPlugins) {
+    val essentialPluginDescription = pluginById[essentialPlugin]
+    if(essentialPluginDescription == null) continue
+    essentialPluginDescription.requiredDependencies.filter { it in pluginById }.forEach { requiredPlugin ->
+      println("$essentialPlugin depends on $requiredPlugin")
+      if (requiredPlugin !in essentialPlugins) {
+        softly.fail<Unit>("$essentialPlugin depends on non-essential plugin $requiredPlugin")
+      }
+    }
+  }
+  softly.assertAll()
+}
+
+private data class PluginDescription(
+  val pluginId: String,
+  val requiredDependencies: Set<String> = emptySet()
+)
+
+private fun getPluginByIdMap(context: BuildContext): Map<String, PluginDescription> {
+  val pluginMap = collectPluginDescriptors(
+    skipImplementationDetailPlugins = true, //it's not possible to disable implementation detail plugin
+    skipBundledPlugins = false,
+    honorCompatiblePluginsToIgnore = false,
+    context = context
+  )
+
+  val plugins = ArrayList<PluginDescription>()
+  for (plugin in pluginMap.values.toSet()) {
+    plugins.add(PluginDescription(pluginId = plugin.id, requiredDependencies = plugin.requiredDependencies))
+  }
+  return plugins.associateBy { it.pluginId }
+}