[Test] Create test setup for IC and IR plugin referencing some external function

^KT-79504

Author: demiurg906

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLReversedSandboxBackBoxTestGenerated.java

@@ -81,3 +81,9 @@ annotation class EmitMetadata(val value: Int)
 
 @Retention(AnnotationRetention.SOURCE)
 annotation class GenerateBodyUsingEmittedMetadata
+
+/**
+ * Signals [IrTransformerForICTesting] to insert a call of the specified function
+ * in the annotated function
+ */
+annotation class CallSpecifiedFunction(val functionName: String)

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLSandboxBackBoxTestGenerated.java

@@ -0,0 +1,8 @@
+package foo
+
+var result = "Error"
+
+fun functionToCall(): String {
+    result = "OK"
+    return "OK"
+}

plugins/plugin-sandbox/plugin-annotations/src/commonMain/kotlin/org/jetbrains/kotlin/plugin/sandbox/annotations.kt

@@ -0,0 +1,8 @@
+package foo
+
+var result = "Error"
+
+fun functionToCall(): Int {
+    result = "OK"
+    return 1
+}

plugins/plugin-sandbox/plugin-sandbox-ic-test/testData/pureKotlin/referenceFunctionFromIrPlugin/a.kt

@@ -0,0 +1,17 @@
+package foo
+
+import org.jetbrains.kotlin.plugin.sandbox.CallSpecifiedFunction
+
+@CallSpecifiedFunction("foo.functionToCall")
+fun test(): Int {
+    val x = 1
+    val y = 2
+    return x + y
+}
+
+fun box(): String {
+    if (result != "Error") return result
+    val testResult = test()
+    if (testResult != 3) return "Error: $testResult"
+    return result
+}

plugins/plugin-sandbox/plugin-sandbox-ic-test/testData/pureKotlin/referenceFunctionFromIrPlugin/a.kt.new

@@ -0,0 +1,8 @@
+================ Step #1 =================
+
+Compiling files:
+  src/a.kt
+End of files
+Exit code: OK
+
+------------------------------------------

plugins/plugin-sandbox/plugin-sandbox-ic-test/testData/pureKotlin/referenceFunctionFromIrPlugin/b.kt

@@ -0,0 +1 @@
+Test fails due to difference between bodies in b.kt in clean and IC builds

plugins/plugin-sandbox/plugin-sandbox-ic-test/testData/pureKotlin/referenceFunctionFromIrPlugin/build.log

@@ -25,6 +25,7 @@ class GeneratedDeclarationsIrBodyFiller : IrGenerationExtension {
             SourceElementChecker(pluginContext),
             MetadataExtensionEmitter(pluginContext),
             MetadataExtensionExtractor(pluginContext),
+            IrTransformerForICTesting(pluginContext),
         )
 
         for (transformer in transformers) {