Write test to compare FIR from light tree with FIR from PSI

compiler/fir/lightTree/src/org/jetbrains/kotlin/fir/lightTree/Converter.kt

@@ -69,7 +69,7 @@ class Converter(
         for (kid in kidsArray) {
             if (kid == null) continue
             val tokenType = kid.tokenType
-            if (COMMENTS.contains(tokenType) || tokenType == WHITE_SPACE || tokenType == SEMICOLON || tokenType == COLON) continue
+            if (COMMENTS.contains(tokenType) || tokenType == WHITE_SPACE || tokenType == SEMICOLON) continue
             f(kid)
         }
     }
@@ -641,11 +641,12 @@ class Converter(
                 is KtNodeType,
                 is KtConstantExpressionElementType,
                 is KtDotQualifiedExpressionElementType,
-                is KtStringTemplateExpressionElementType -> firExpression = visitExpression(it) //TODO implement
+                is KtStringTemplateExpressionElementType,
+                REFERENCE_EXPRESSION -> firExpression = visitExpression(it) //TODO implement
             }
         }
 
-        returnType = if (firBlock != null || modifiers.inheritanceModifier == InheritanceModifier.ABSTRACT) {
+        returnType = if (firBlock != null || (firBlock == null && firExpression == null)) {
             returnType ?: implicitUnitType
         } else {
             returnType ?: implicitType
@@ -714,7 +715,8 @@ class Converter(
                 is KtNodeType,
                 is KtConstantExpressionElementType,
                 is KtDotQualifiedExpressionElementType,
-                is KtStringTemplateExpressionElementType -> firExpression = visitExpression(it) //TODO implement
+                is KtStringTemplateExpressionElementType,
+                REFERENCE_EXPRESSION -> firExpression = visitExpression(it) //TODO implement
             }
         }
 
@@ -818,7 +820,7 @@ class Converter(
                 COLON -> isReturnType = true
                 TYPE_REFERENCE -> if (isReturnType) returnType = convertType(it) else receiverType = convertType(it)
                 TYPE_CONSTRAINT_LIST -> typeConstraints += convertTypeConstraints(it)
-                BY_KEYWORD -> isDelegate = true
+                PROPERTY_DELEGATE -> isDelegate = true
                 VAR_KEYWORD -> isVar = true
                 PROPERTY_ACCESSOR ->
                     if (it.toString().contains("get")) //TODO make it better
@@ -828,7 +830,8 @@ class Converter(
                 is KtNodeType,
                 is KtConstantExpressionElementType,
                 is KtDotQualifiedExpressionElementType,
-                is KtStringTemplateExpressionElementType -> firExpression = visitExpression(it) //TODO implement
+                is KtStringTemplateExpressionElementType,
+                REFERENCE_EXPRESSION -> firExpression = visitExpression(it) //TODO implement
             }
         }
 
@@ -901,7 +904,8 @@ class Converter(
                 is KtNodeType,
                 is KtConstantExpressionElementType,
                 is KtDotQualifiedExpressionElementType,
-                is KtStringTemplateExpressionElementType -> firExpression = visitExpression(it) //TODO implement
+                is KtStringTemplateExpressionElementType,
+                REFERENCE_EXPRESSION -> firExpression = visitExpression(it) //TODO implement
             }
         }
 
@@ -936,7 +940,8 @@ class Converter(
                 is KtNodeType,
                 is KtConstantExpressionElementType,
                 is KtDotQualifiedExpressionElementType,
-                is KtStringTemplateExpressionElementType -> firExpression = visitExpression(it) //TODO implement
+                is KtStringTemplateExpressionElementType,
+                REFERENCE_EXPRESSION -> firExpression = visitExpression(it) //TODO implement
             }
         }
 
@@ -1360,12 +1365,15 @@ class Converter(
         annotationUseSiteTarget: AnnotationUseSiteTarget?
     ): FirAnnotationCall {
         //TODO not implemented
+        val pair = convertConstructorInvocation(unescapedAnnotation)
         return FirAnnotationCallImpl(
             session,
             null,
             annotationUseSiteTarget,
-            FirErrorTypeRefImpl(session, null, "not implemented") //TODO not implemented
+            pair.first
-        )
+        ).apply {
+            arguments += pair.second
+        }
     }
 
     private fun visitExpression(expression: LighterASTNode): FirExpression {

compiler/fir/lightTree/tests/org/jetbrains/kotlin/fir/lightTree/LightTree2FirConverterTotalKotlin.kt

@@ -5,19 +5,13 @@
 
 package org.jetbrains.kotlin.fir.lightTree
 
-import com.intellij.lang.impl.PsiBuilderFactoryImpl
 import com.intellij.openapi.util.io.FileUtil
 import com.intellij.openapi.vfs.CharsetToolkit
-import com.intellij.psi.PsiManager
 import com.intellij.psi.impl.DebugUtil
-import com.intellij.psi.impl.PsiManagerEx
-import com.intellij.testFramework.LightVirtualFile
 import com.intellij.testFramework.TestDataPath
 import com.intellij.util.PathUtil
 import org.jetbrains.kotlin.fir.FirRenderer
 import org.jetbrains.kotlin.fir.builder.AbstractRawFirBuilderTestCase
-import org.jetbrains.kotlin.idea.KotlinFileType
-import org.jetbrains.kotlin.parsing.KotlinParser
 import org.jetbrains.kotlin.parsing.KotlinParserDefinition
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.test.JUnit3RunnerWithInners

compiler/fir/lightTree/tests/org/jetbrains/kotlin/fir/lightTree/TreesCompareTest.kt

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. 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.fir.lightTree
+
+import com.intellij.openapi.util.io.FileUtil
+import com.intellij.openapi.vfs.CharsetToolkit
+import com.intellij.testFramework.TestDataPath
+import com.intellij.util.PathUtil
+import junit.framework.TestCase
+import org.jetbrains.kotlin.fir.FirRenderer
+import org.jetbrains.kotlin.fir.builder.AbstractRawFirBuilderTestCase
+import org.jetbrains.kotlin.parsing.KotlinParserDefinition
+import org.jetbrains.kotlin.psi.KtFile
+import org.jetbrains.kotlin.test.JUnit3RunnerWithInners
+import org.junit.runner.RunWith
+import java.io.File
+
+@TestDataPath("\$PROJECT_ROOT")
+@RunWith(JUnit3RunnerWithInners::class)
+class TreesCompareTest: AbstractRawFirBuilderTestCase() {
+    fun testCompare() {
+        val path = System.getProperty("user.dir")
+        val root = File(path)
+        var counter = 0
+        var errorCounter = 0
+
+        val parserDefinition = KotlinParserDefinition()
+        val lexer = parserDefinition.createLexer(myProject)
+        val lightTreeConverter = LightTree2Fir(true, parserDefinition, lexer)
+
+        println("BASE PATH: $path")
+        for (file in root.walkTopDown()) {
+            if (file.isDirectory) continue
+            if (file.path.contains("testData") || file.path.contains("resources")) continue
+            if (file.extension != "kt") continue
+
+            val text = FileUtil.loadFile(file, CharsetToolkit.UTF8, true).trim()
+
+            //light tree
+            val firFileFromLightTree = lightTreeConverter.buildFirFile(text, file.name)
+            val treeFromLightTree = StringBuilder().also { FirRenderer(it).visitFile(firFileFromLightTree) }.toString()
+
+            //psi
+            val ktFile = createPsiFile(FileUtil.getNameWithoutExtension(PathUtil.getFileName(file.path)), text) as KtFile
+            val firFileFromPsi = ktFile.toFirFile(stubMode = true)
+            val treeFromPsi = StringBuilder().also { FirRenderer(it).visitFile(firFileFromPsi) }.toString()
+
+            if (treeFromLightTree != treeFromPsi){
+                errorCounter++;
+                //TestCase.assertEquals(treeFromPsi, treeFromLightTree)
+            }
+            counter++
+        }
+        println("All scanned files: $counter")
+        println("Files that aren't equal to FIR: $errorCounter")
+    }
+}