From 0d8cdb7bdb5fa4e00568254b4be77d2f4398d0af Mon Sep 17 00:00:00 2001
From: Nikita Bobko <nikita.bobko@jetbrains.com>
Date: Fri, 4 Dec 2020 15:45:15 +0300
Subject: [PATCH] Fix double registered "com.intellij.psi.classFileDecompiler"
 for 203 platform

This commit addresses 1243c641296e74a572a4f274df72a4cda60635c6 in intellij
In intellij they added registration of "com.intellij.psi.classFileDecompiler" in
`JavaCoreApplicationEnvironment`. And because the `KotlinCoreApplicationEnvironment` inherits
`JavaCoreApplicationEnvironment` we don't need to register this EP ourselves.

This commit fixes in 203 tests + 1.4.30 compiler:
```
java.lang.RuntimeException: Duplicate registration for EP 'com.intellij.psi.classFileDecompiler': first in com.intellij.openapi.extensions.DefaultPluginDescriptor@44f464d1, second in PluginDescriptor(name=org.jetbrains.kotlin, id=org.jetbrains.kotlin, path=/home/builduser/.m2/repository/org/jetbrains/kotlin/kotlin-compiler-for-ide/1.4.30-M1-30/kotlin-compiler-for-ide-1.4.30-M1-30.jar, version=1.2)
	at com.intellij.openapi.components.ComponentManager.createError(ComponentManager.java:167)
	at com.intellij.openapi.extensions.impl.ExtensionsAreaImpl.registerExtensionPoints(ExtensionsAreaImpl.java:262)
	at com.intellij.ide.plugins.PluginManagerCore.registerExtensionPointAndExtensions(PluginManagerCore.java:1334)
	...
```
---
 .../cli/cli-common/resources/META-INF/extensions/core.xml  | 2 ++
 .../kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt       | 7 ++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/compiler/cli/cli-common/resources/META-INF/extensions/core.xml b/compiler/cli/cli-common/resources/META-INF/extensions/core.xml
index da66522edb3..bc2b356021d 100644
--- a/compiler/cli/cli-common/resources/META-INF/extensions/core.xml
+++ b/compiler/cli/cli-common/resources/META-INF/extensions/core.xml
@@ -2,6 +2,8 @@
     <id>org.jetbrains.kotlin</id>
     <version>1.2</version>
 
+    <!-- Don't add more extension points here! Logic in KotlinCoreEnvironment assumes that there is only one EP.  -->
+    <!-- And this file should be removed once 202 is no longer supported -->
     <extensionPoints>
         <extensionPoint qualifiedName="com.intellij.psi.classFileDecompiler"
                         interface="com.intellij.psi.compiled.ClassFileDecompilers$Decompiler"
diff --git a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt
index 5c1cda1d7cc..1624b9df21b 100644
--- a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt
+++ b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt
@@ -40,6 +40,7 @@ import com.intellij.openapi.vfs.*
 import com.intellij.openapi.vfs.impl.ZipHandler
 import com.intellij.psi.PsiElementFinder
 import com.intellij.psi.PsiManager
+import com.intellij.psi.compiled.ClassFileDecompilers
 import com.intellij.psi.impl.JavaClassSupersImpl
 import com.intellij.psi.impl.PsiElementFinderImpl
 import com.intellij.psi.impl.PsiTreeChangePreprocessor
@@ -509,7 +510,11 @@ class KotlinCoreEnvironment private constructor(
             val applicationEnvironment = KotlinCoreApplicationEnvironment.create(parentDisposable, unitTestMode)
 
             registerApplicationExtensionPointsAndExtensionsFrom(configuration, "extensions/compiler.xml")
-            registerApplicationExtensionPointsAndExtensionsFrom(configuration, "extensions/core.xml")
+            // FIX ME WHEN BUNCH 202 REMOVED: this code is required to support compiler bundled to both 202 and 203.
+            // Please, remove "com.intellij.psi.classFileDecompiler" EP registration once 202 is no longer supported by the compiler
+            if (!Extensions.getRootArea().hasExtensionPoint("com.intellij.psi.classFileDecompiler")) {
+                registerApplicationExtensionPointsAndExtensionsFrom(configuration, "extensions/core.xml")
+            }
 
             registerApplicationServicesForCLI(applicationEnvironment)
             registerApplicationServices(applicationEnvironment)