diff --git a/idea/idea-completion/testData/basic/common/annotations/Annotated.kt b/idea/idea-completion/testData/basic/common/annotations/Annotated.kt
index f2cd74d106d..77141ea24d7 100644
--- a/idea/idea-completion/testData/basic/common/annotations/Annotated.kt
+++ b/idea/idea-completion/testData/basic/common/annotations/Annotated.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 <caret> class Annotated
 
 // EXIST: annotation
\ No newline at end of file
diff --git a/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName1.kt b/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName1.kt
index b0b93eca6fd..eebe0da6501 100644
--- a/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName1.kt
+++ b/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName1.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar() {
     val handler = { <caret> }
 }
diff --git a/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName4.kt b/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName4.kt
index bb9325e7bd4..2f1cc099daa 100644
--- a/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName4.kt
+++ b/idea/idea-completion/testData/basic/common/lambdaSignature/ParameterName4.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar() {
     val handler = { <caret>
         foo()
diff --git a/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt b/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt
index c83ea3652f4..2a20eafe0a6 100644
--- a/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt
+++ b/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 cl<caret>interface MyClass
 
 // ELEMENT: "class"
diff --git a/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt.after b/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt.after
index 408077d9804..14d74c1b392 100644
--- a/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt.after
+++ b/idea/idea-completion/testData/handlers/basic/ClassKeywordBeforeName.kt.after
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 class <caret>MyClass
 
 // ELEMENT: "class"
diff --git a/idea/idea-completion/testData/weighers/basic/ExactMatchForKeyword.kt b/idea/idea-completion/testData/weighers/basic/ExactMatchForKeyword.kt
index 37afaa2932c..4c30ab4019d 100644
--- a/idea/idea-completion/testData/weighers/basic/ExactMatchForKeyword.kt
+++ b/idea/idea-completion/testData/weighers/basic/ExactMatchForKeyword.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun test() {
     val ifMore = true
     val isFirst = true
diff --git a/idea/idea-completion/testData/weighers/basic/KeywordsLast.kt b/idea/idea-completion/testData/weighers/basic/KeywordsLast.kt
index 5b8a37bda8f..ef591284d2a 100644
--- a/idea/idea-completion/testData/weighers/basic/KeywordsLast.kt
+++ b/idea/idea-completion/testData/weighers/basic/KeywordsLast.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun main(variables: Array<String>) {
     val values = ""
     va<caret>
diff --git a/idea/idea-completion/testData/weighers/basic/LocalsBeforeKeywords.kt b/idea/idea-completion/testData/weighers/basic/LocalsBeforeKeywords.kt
index 1da772909bf..3870f7888da 100644
--- a/idea/idea-completion/testData/weighers/basic/LocalsBeforeKeywords.kt
+++ b/idea/idea-completion/testData/weighers/basic/LocalsBeforeKeywords.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun test() {
     val r = 12
     r<caret>
diff --git a/idea/idea-completion/testData/weighers/basic/LocalsPropertiesKeywords.kt b/idea/idea-completion/testData/weighers/basic/LocalsPropertiesKeywords.kt
index 8aa74430b68..4005f3f2da6 100644
--- a/idea/idea-completion/testData/weighers/basic/LocalsPropertiesKeywords.kt
+++ b/idea/idea-completion/testData/weighers/basic/LocalsPropertiesKeywords.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun test(fals: Int) {
     val falt = 111
     fal<caret>
diff --git a/idea/idea-completion/testData/weighers/basic/ParametersBeforeKeywords.kt b/idea/idea-completion/testData/weighers/basic/ParametersBeforeKeywords.kt
index a4403c50e0e..4347290dfb7 100644
--- a/idea/idea-completion/testData/weighers/basic/ParametersBeforeKeywords.kt
+++ b/idea/idea-completion/testData/weighers/basic/ParametersBeforeKeywords.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun bar(breach: Int) {
     while (true)
         bre<caret>
diff --git a/idea/idea-completion/testData/weighers/basic/TopLevelKeywordWithClassName.kt b/idea/idea-completion/testData/weighers/basic/TopLevelKeywordWithClassName.kt
index 19f67f34ab4..ffe03d6ae11 100644
--- a/idea/idea-completion/testData/weighers/basic/TopLevelKeywordWithClassName.kt
+++ b/idea/idea-completion/testData/weighers/basic/TopLevelKeywordWithClassName.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 cla<caret>
 
 // ORDER: class
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfNestedBlock.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfNestedBlock.kt
index 287fb10b056..0707028cfe2 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfNestedBlock.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfNestedBlock.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun() {}
 
 fun usage() {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfTopLevelBlock.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfTopLevelBlock.kt
index 40fe046be2d..e2b2b584790 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfTopLevelBlock.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/BeginOfTopLevelBlock.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun() {}
 
 fun usage() {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/EndOfTopLevelBlock.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/EndOfTopLevelBlock.kt
index 897b9cc9a9b..0e6434b3055 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/EndOfTopLevelBlock.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/EndOfTopLevelBlock.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun() {}
 
 fun usage() {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithBody.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithBody.kt
index 3a2bee48ddc..08772039c55 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithBody.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithBody.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun() {}
 
 fun usage() {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithoutBody.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithoutBody.kt
index 0339f7f8e29..2722484ff2d 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithoutBody.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/noReturnType/ForWithoutBody.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun() {}
 
 fun usage() {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfNestedBlock.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfNestedBlock.kt
index dbe5dd2ab1d..0c461a0e465 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfNestedBlock.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfNestedBlock.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun(): Int = 10
 
 fun usage(): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfTopLevelBlock.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfTopLevelBlock.kt
index 542bb01f4b0..3c81fed8479 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfTopLevelBlock.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/BeginOfTopLevelBlock.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun(): Int = 10
 
 fun usage(): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithBody.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithBody.kt
index 2117788c584..4c670030f7c 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithBody.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithBody.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun(): Int = 10
 
 fun usage(): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithoutBody.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithoutBody.kt
index 82f905cc8cf..e221b927dd1 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithoutBody.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/ForWithoutBody.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun(): Int = 10
 
 fun usage(): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InElvisInReturn.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InElvisInReturn.kt
index 4ec2f55f09d..31aa0a33773 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InElvisInReturn.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InElvisInReturn.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun reportError(): Nothing
 
 fun usage(a: Int?): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InIfAsReturnedExpression.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InIfAsReturnedExpression.kt
index d40a523b7a9..01aa60ac47b 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InIfAsReturnedExpression.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InIfAsReturnedExpression.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun reportError(): Nothing
 
 fun usage(a: Int?): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InNotElvisBinaryOperator.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InNotElvisBinaryOperator.kt
index 8fa85626aa2..f017a3775b0 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InNotElvisBinaryOperator.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InNotElvisBinaryOperator.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun returnFun(): String = ""
 
 fun usage(a: Int?): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenAsReturnedExpression.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenAsReturnedExpression.kt
index 760af7e23c2..26994b6edd8 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenAsReturnedExpression.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenAsReturnedExpression.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun reportError(): Nothing
 
 fun usage(a: Int?): Int {
diff --git a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenWithBodyAsReturnedExpression.kt b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenWithBodyAsReturnedExpression.kt
index 760af7e23c2..26994b6edd8 100644
--- a/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenWithBodyAsReturnedExpression.kt
+++ b/idea/idea-completion/testData/weighers/basic/contextualReturn/withReturnType/InWhenWithBodyAsReturnedExpression.kt
@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 fun reportError(): Nothing
 
 fun usage(a: Int?): Int {