diff --git a/plugins/kotlin/idea/tests/testData/diagnosticMessage/abstractBaseClassMemberNotImplemented1.txt b/plugins/kotlin/idea/tests/testData/diagnosticMessage/abstractBaseClassMemberNotImplemented1.txt
index dc73fbf39d0b..5eb4f97391bd 100644
--- a/plugins/kotlin/idea/tests/testData/diagnosticMessage/abstractBaseClassMemberNotImplemented1.txt
+++ b/plugins/kotlin/idea/tests/testData/diagnosticMessage/abstractBaseClassMemberNotImplemented1.txt
@@ -1,2 +1,2 @@
 <!-- abstractBaseClassMemberNotImplemented1 -->
-Class 'E' must be declared abstract or implement abstract base class member public abstract fun f(): T4 defined in D
\ No newline at end of file
+Class 'E' is not abstract and does not implement abstract base class member public abstract fun f(): T4 defined in D
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/function/noDirectOverridesNeeded.kt b/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/function/noDirectOverridesNeeded.kt
index d03e3f255a87..5e8dc49829fe 100644
--- a/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/function/noDirectOverridesNeeded.kt
+++ b/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/function/noDirectOverridesNeeded.kt
@@ -1,5 +1,5 @@
 // IS_APPLICABLE: false
-// ERROR: Class 'C' must be declared abstract or implement abstract base class member public abstract fun foo(): Int defined in B
+// ERROR: Class 'C' is not abstract and does not implement abstract base class member public abstract fun foo(): Int defined in B
 interface A {
     fun <caret>foo(): Int
 }
diff --git a/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/property/noDirectOverridesNeeded.kt b/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/property/noDirectOverridesNeeded.kt
index 4edd5ca9a14e..0db1aaf81c23 100644
--- a/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/property/noDirectOverridesNeeded.kt
+++ b/plugins/kotlin/idea/tests/testData/intentions/implementAbstractMember/property/noDirectOverridesNeeded.kt
@@ -1,5 +1,5 @@
 // IS_APPLICABLE: false
-// ERROR: Class 'C' must be declared abstract or implement abstract base class member public abstract val foo: Int defined in B
+// ERROR: Class 'C' is not abstract and does not implement abstract base class member public abstract val foo: Int defined in B
 interface A {
     val <caret>foo: Int
 }
diff --git a/plugins/kotlin/idea/tests/testData/intentions/implementAsConstructorParameter/noDirectOverridesNeeded.kt b/plugins/kotlin/idea/tests/testData/intentions/implementAsConstructorParameter/noDirectOverridesNeeded.kt
index 4edd5ca9a14e..0db1aaf81c23 100644
--- a/plugins/kotlin/idea/tests/testData/intentions/implementAsConstructorParameter/noDirectOverridesNeeded.kt
+++ b/plugins/kotlin/idea/tests/testData/intentions/implementAsConstructorParameter/noDirectOverridesNeeded.kt
@@ -1,5 +1,5 @@
 // IS_APPLICABLE: false
-// ERROR: Class 'C' must be declared abstract or implement abstract base class member public abstract val foo: Int defined in B
+// ERROR: Class 'C' is not abstract and does not implement abstract base class member public abstract val foo: Int defined in B
 interface A {
     val <caret>foo: Int
 }
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/abstract/makeEnumEntryAbstract.kt b/plugins/kotlin/idea/tests/testData/quickfix/abstract/makeEnumEntryAbstract.kt
index b3a12edc7df9..8d34c8a75b26 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/abstract/makeEnumEntryAbstract.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/abstract/makeEnumEntryAbstract.kt
@@ -1,6 +1,6 @@
 // "Make 'A' abstract" "false"
 // ACTION: Implement members
-// ERROR: Class 'A' must be declared abstract or implement abstract member public abstract fun foo(): Unit defined in E
+// ERROR: Class 'A' is not abstract and does not implement abstract member public abstract fun foo(): Unit defined in E
 
 enum class E {
     <caret>A;
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/memberExtensionProperty.kt b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/memberExtensionProperty.kt
index d53af91b8ee7..d50fc235d260 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/memberExtensionProperty.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/memberExtensionProperty.kt
@@ -3,7 +3,7 @@
 // ACTION: Make private
 // ACTION: Make protected
 // ACTION: Make 'n' abstract
-// ERROR: Property must be initialized or be abstract
+// ERROR: Extension property must have accessors or be abstract
 class A {
     <caret>val Int.n: Int
 }
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionProperty.kt b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionProperty.kt
index 0a0a69db6b91..42dbf07521dc 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionProperty.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionProperty.kt
@@ -1,5 +1,5 @@
 // "class org.jetbrains.kotlin.idea.quickfix.InitializePropertyQuickFixFactory$AddInitializerFix" "false"
 // ACTION: Make internal
 // ACTION: Make private
-// ERROR: Property must be initialized
+// ERROR: Extension property must have accessors or be abstract
 <caret>val Int.n: Int
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionPropertySetterOnly.kt b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionPropertySetterOnly.kt
index 0a0a69db6b91..42dbf07521dc 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionPropertySetterOnly.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/addInitializer/topLevelExtensionPropertySetterOnly.kt
@@ -1,5 +1,5 @@
 // "class org.jetbrains.kotlin.idea.quickfix.InitializePropertyQuickFixFactory$AddInitializerFix" "false"
 // ACTION: Make internal
 // ACTION: Make private
-// ERROR: Property must be initialized
+// ERROR: Extension property must have accessors or be abstract
 <caret>val Int.n: Int
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt b/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt
index 83d6713c9ecc..0bb854097c49 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt
@@ -1,5 +1,5 @@
 // "Create class 'Foo'" "true"
-// ERROR: Class 'Foo' must be declared abstract or implement abstract member public abstract operator fun getValue(thisRef: A<T>, property: KProperty<*>): B defined in kotlin.properties.ReadOnlyProperty
+// ERROR: Class 'Foo' is not abstract and does not implement abstract member public abstract operator fun getValue(thisRef: A<T>, property: KProperty<*>): B defined in kotlin.properties.ReadOnlyProperty
 
 open class B
 
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt.after b/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt.after
index 9fdd368955a6..9c6c1e23244f 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt.after
+++ b/plugins/kotlin/idea/tests/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberValDelegateRuntime.kt.after
@@ -1,7 +1,7 @@
 import kotlin.properties.ReadOnlyProperty
 
 // "Create class 'Foo'" "true"
-// ERROR: Class 'Foo' must be declared abstract or implement abstract member public abstract operator fun getValue(thisRef: A<T>, property: KProperty<*>): B defined in kotlin.properties.ReadOnlyProperty
+// ERROR: Class 'Foo' is not abstract and does not implement abstract member public abstract operator fun getValue(thisRef: A<T>, property: KProperty<*>): B defined in kotlin.properties.ReadOnlyProperty
 
 open class B
 
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForAnonymousObject.kt b/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForAnonymousObject.kt
index f13947c5cf3f..bd36c6b8c39e 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForAnonymousObject.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForAnonymousObject.kt
@@ -2,7 +2,7 @@
 // ACTION: Implement members
 // ACTION: Split property declaration
 // ACTION: Convert object literal to class
-// ERROR: Object must be declared abstract or implement abstract member public abstract fun foo(): Unit defined in T
+// ERROR: Object is not abstract and does not implement abstract member public abstract fun foo(): Unit defined in T
 interface T {
     fun foo()
 }
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForObject.kt b/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForObject.kt
index 91e215f10ae3..10537eeab9eb 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForObject.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/modifiers/noAbstractForObject.kt
@@ -3,7 +3,7 @@
 // ACTION: Implement members
 // ACTION: Move 'Some' to separate file
 // ACTION: Rename file to Some.kt
-// ERROR: Object 'Some' must be declared abstract or implement abstract member public abstract fun foo(): Unit defined in T
+// ERROR: Object 'Some' is not abstract and does not implement abstract member public abstract fun foo(): Unit defined in T
 interface T {
     fun foo()
 }
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/moveToConstructorParameters/memberExtensionProperty.kt b/plugins/kotlin/idea/tests/testData/quickfix/moveToConstructorParameters/memberExtensionProperty.kt
index 8be009cbae8a..b047ccb67073 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/moveToConstructorParameters/memberExtensionProperty.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/moveToConstructorParameters/memberExtensionProperty.kt
@@ -3,7 +3,7 @@
 // ACTION: Make internal
 // ACTION: Make private
 // ACTION: Make protected
-// ERROR: Property must be initialized or be abstract
+// ERROR: Extension property must have accessors or be abstract
 class A {
     <caret>val Int.n: Int
 }
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterFunction.kt b/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterFunction.kt
index f268e3f662b0..a2cd0aa01de3 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterFunction.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterFunction.kt
@@ -5,7 +5,7 @@
 // ACTION: Make internal
 // ACTION: Make private
 // ACTION: Move 'A' to separate file
-// ERROR: Class 'A' must be declared abstract or implement abstract member public abstract fun foo(): Int defined in I
+// ERROR: Class 'A' is not abstract and does not implement abstract member public abstract fun foo(): Int defined in I
 interface I {
     fun foo(): Int
 }
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterInObject.kt b/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterInObject.kt
index 9f2d1c08335f..b69abdc8c869 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterInObject.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/override/implemenAsConstructorParameterInObject.kt
@@ -4,7 +4,7 @@
 // ACTION: Make internal
 // ACTION: Make private
 // ACTION: Move 'A' to separate file
-// ERROR: Object 'A' must be declared abstract or implement abstract member public abstract val foo: Int defined in I
+// ERROR: Object 'A' is not abstract and does not implement abstract member public abstract val foo: Int defined in I
 interface I {
     val foo: Int
 }
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt b/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt
index 143dbcc2cf2e..9d81e08818e9 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt
+++ b/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt
@@ -1,5 +1,5 @@
 // "Change function signature..." "true"
-// ERROR: Class 'B' must be declared abstract or implement abstract member public abstract fun f(a: String): Unit defined in A
+// ERROR: Class 'B' is not abstract and does not implement abstract member public abstract fun f(a: String): Unit defined in A
 interface A {
     fun f(a: Int)
     fun f(a: String)
diff --git a/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt.after b/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt.after
index 141cdf7cf9c2..5f1df06a1d4e 100644
--- a/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt.after
+++ b/plugins/kotlin/idea/tests/testData/quickfix/override/nothingToOverride/addParameterMultiple.kt.after
@@ -1,5 +1,5 @@
 // "Change function signature..." "true"
-// ERROR: Class 'B' must be declared abstract or implement abstract member public abstract fun f(a: String): Unit defined in A
+// ERROR: Class 'B' is not abstract and does not implement abstract member public abstract fun f(a: String): Unit defined in A
 interface A {
     fun f(a: Int)
     fun f(a: String)
diff --git a/plugins/kotlin/j2k/old/tests/testData/fileOrElement/comments/comments.kt b/plugins/kotlin/j2k/old/tests/testData/fileOrElement/comments/comments.kt
index 633f5a3fb8a6..4796775a2b7b 100644
--- a/plugins/kotlin/j2k/old/tests/testData/fileOrElement/comments/comments.kt
+++ b/plugins/kotlin/j2k/old/tests/testData/fileOrElement/comments/comments.kt
@@ -1,4 +1,4 @@
-// ERROR: Class 'A' must be declared abstract or implement abstract member public abstract fun run(): Unit defined in java.lang.Runnable
+// ERROR: Class 'A' is not abstract and does not implement abstract member public abstract fun run(): Unit defined in java.lang.Runnable
 package foo
 
 // we use package 'foo'
diff --git a/plugins/kotlin/jps/jps-plugin/testData/incremental/classHierarchyAffected/overrideImplicit/build.log b/plugins/kotlin/jps/jps-plugin/testData/incremental/classHierarchyAffected/overrideImplicit/build.log
index 3370de7c993e..2533be1703d3 100644
--- a/plugins/kotlin/jps/jps-plugin/testData/incremental/classHierarchyAffected/overrideImplicit/build.log
+++ b/plugins/kotlin/jps/jps-plugin/testData/incremental/classHierarchyAffected/overrideImplicit/build.log
@@ -19,7 +19,7 @@ End of files
 Exit code: ABORT
 ------------------------------------------
 COMPILATION FAILED
-Class 'BA' must be declared abstract or implement abstract member public abstract fun f(c: C<Any>): Unit defined in A
+Class 'BA' is not abstract and does not implement abstract member public abstract fun f(c: C<Any>): Unit defined in A
 
 ================ Step #2 =================
 
@@ -31,4 +31,4 @@ Compiling files:
   src/BA.kt
 End of files
 Exit code: OK
-------------------------------------------
+------------------------------------------
\ No newline at end of file
diff --git a/plugins/kotlin/jps/jps-plugin/testData/incremental/pureKotlin/conflictingPlatformDeclarations/build.log b/plugins/kotlin/jps/jps-plugin/testData/incremental/pureKotlin/conflictingPlatformDeclarations/build.log
index 6c49ba3e152e..470833135793 100644
--- a/plugins/kotlin/jps/jps-plugin/testData/incremental/pureKotlin/conflictingPlatformDeclarations/build.log
+++ b/plugins/kotlin/jps/jps-plugin/testData/incremental/pureKotlin/conflictingPlatformDeclarations/build.log
@@ -12,8 +12,8 @@ Exit code: ABORT
 ------------------------------------------
 COMPILATION FAILED
 Platform declaration clash: The following declarations have the same JVM signature (function(Ljava/util/List;)V):
-    fun function(list: List<Any>): Unit
-    fun function(list: List<String>): Unit
+    fun function(list: List<Any>): Unit defined in test
+    fun function(list: List<String>): Unit defined in test
 Platform declaration clash: The following declarations have the same JVM signature (function(Ljava/util/List;)V):
-    fun function(list: List<Any>): Unit
-    fun function(list: List<String>): Unit
\ No newline at end of file
+    fun function(list: List<Any>): Unit defined in test
+    fun function(list: List<String>): Unit defined in test
\ No newline at end of file