Allow specify path of compiler extension points for ide tests

compiler/cli/src/org/jetbrains/kotlin/cli/common/CLIConfigurationKeys.java

@@ -51,6 +51,10 @@ public class CLIConfigurationKeys {
     public static final CompilerConfigurationKey<Integer> REPEAT_COMPILE_MODULES =
             CompilerConfigurationKey.create("debug key for profiling, repeats compileModules");
 
+    // used in FIR IDE uast tests
+    public static final CompilerConfigurationKey<File> PATH_TO_KOTLIN_COMPILER_JAR =
+            CompilerConfigurationKey.create("jar of Kotlin compiler in Kotlin plugin");
+
     private CLIConfigurationKeys() {
     }
 }

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt

@@ -566,6 +566,7 @@ class KotlinCoreEnvironment private constructor(
                     ?: PathUtil.getResourcePathForClass(this::class.java).takeIf { it.hasConfigFile(configFilePath) }
                     // hack for load extensions when compiler run directly from project directory (e.g. in tests)
                     ?: File("compiler/cli/cli-common/resources").takeIf { it.hasConfigFile(configFilePath) }
+                    ?: configuration.get(CLIConfigurationKeys.PATH_TO_KOTLIN_COMPILER_JAR)?.takeIf { it.hasConfigFile(configFilePath) }
                     ?: throw IllegalStateException(
                         "Unable to find extension point configuration $configFilePath " +
                                 "(cp:\n  ${(Thread.currentThread().contextClassLoader as? UrlClassLoader)?.urls?.joinToString("\n  ") { it.file }})"