diff --git a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.fir.kt b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.fir.kt
index 366aee5408e..1a38660d1ca 100644
--- a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.fir.kt
+++ b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.fir.kt
@@ -4,7 +4,7 @@
 
 import kotlin.contracts.*
 
-class Foo {
+open class Foo {
     fun myRun(block: () -> Unit) {
         contract {
             callsInPlace(block, InvocationKind.EXACTLY_ONCE)
@@ -12,17 +12,46 @@ class Foo {
         block()
     }
 
-    fun require(x: Boolean) {
+    fun myRequire(x: Boolean) {
         contract { returns() implies (x) }
     }
+
+    inline fun <reified T> assertIs(value: Any) {
+        <!WRONG_IMPLIES_CONDITION!>contract { returns() implies (value is T) }<!>
+    }
+}
+
+class Bar : Foo() {
+    fun test_1(x: Any) {
+        myRequire(x is String)
+        x.length
+    }
+
+    fun test_2(x: Any) {
+        assertIs<String>(x)
+        x.length
+    }
+
+    fun test_3(): Int {
+        val x: Int
+        myRun {
+            x = 1
+        }
+        return x + 1
+    }
 }
 
 fun test_1(foo: Foo, x: Any) {
-    foo.require(x is String)
+    foo.myRequire(x is String)
     x.length
 }
 
-fun test_2(foo: Foo): Int {
+fun test_2(foo: Foo, x: Any) {
+    foo.assertIs<String>(x)
+    x.length
+}
+
+fun test_3(foo: Foo): Int {
     val x: Int
     foo.myRun {
         x = 1
diff --git a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.kt b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.kt
index 520a8571f8c..f5563df584f 100644
--- a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.kt
+++ b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.kt
@@ -4,7 +4,7 @@
 
 import kotlin.contracts.*
 
-class Foo {
+open class Foo {
     fun myRun(block: () -> Unit) {
         contract {
             callsInPlace(block, InvocationKind.EXACTLY_ONCE)
@@ -12,17 +12,46 @@ class Foo {
         block()
     }
 
-    fun require(x: Boolean) {
+    fun myRequire(x: Boolean) {
         contract { returns() implies (x) }
     }
+
+    inline fun <reified T> assertIs(value: Any) {
+        contract { returns() implies (value is T) }
+    }
+}
+
+class Bar : Foo() {
+    fun test_1(x: Any) {
+        myRequire(x is String)
+        <!DEBUG_INFO_SMARTCAST!>x<!>.length
+    }
+
+    fun test_2(x: Any) {
+        assertIs<String>(x)
+        x.<!UNRESOLVED_REFERENCE!>length<!>
+    }
+
+    fun test_3(): Int {
+        val x: Int
+        myRun {
+            x = 1
+        }
+        return x + 1
+    }
 }
 
 fun test_1(foo: Foo, x: Any) {
-    foo.require(x is String)
+    foo.myRequire(x is String)
     <!DEBUG_INFO_SMARTCAST!>x<!>.length
 }
 
-fun test_2(foo: Foo): Int {
+fun test_2(foo: Foo, x: Any) {
+    foo.assertIs<String>(x)
+    <!DEBUG_INFO_SMARTCAST!>x<!>.length
+}
+
+fun test_3(foo: Foo): Int {
     val x: Int
     foo.myRun {
         x = 1
diff --git a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.txt b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.txt
index 2a7eb3c2ea9..f8144d90e8d 100644
--- a/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.txt
+++ b/compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/contractsOnMembers.txt
@@ -1,17 +1,41 @@
 package
 
 public fun test_1(/*0*/ foo: Foo, /*1*/ x: kotlin.Any): kotlin.Unit
-public fun test_2(/*0*/ foo: Foo): kotlin.Int
+public fun test_2(/*0*/ foo: Foo, /*1*/ x: kotlin.Any): kotlin.Unit
+public fun test_3(/*0*/ foo: Foo): kotlin.Int
+
+public final class Bar : Foo {
+    public constructor Bar()
+    public final override /*1*/ inline /*fake_override*/ fun </*0*/ reified T> assertIs(/*0*/ value: kotlin.Any): kotlin.Unit
+        Returns(WILDCARD) -> value is T
 
-public final class Foo {
-    public constructor Foo()
     public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun myRequire(/*0*/ x: kotlin.Boolean): kotlin.Unit
+        Returns(WILDCARD) -> x
+
+    public final override /*1*/ /*fake_override*/ fun myRun(/*0*/ block: () -> kotlin.Unit): kotlin.Unit
+        CallsInPlace(block, EXACTLY_ONCE)
+
+    public final fun test_1(/*0*/ x: kotlin.Any): kotlin.Unit
+    public final fun test_2(/*0*/ x: kotlin.Any): kotlin.Unit
+    public final fun test_3(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class Foo {
+    public constructor Foo()
+    public final inline fun </*0*/ reified T> assertIs(/*0*/ value: kotlin.Any): kotlin.Unit
+        Returns(WILDCARD) -> value is T
+
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final fun myRequire(/*0*/ x: kotlin.Boolean): kotlin.Unit
+        Returns(WILDCARD) -> x
+
     public final fun myRun(/*0*/ block: () -> kotlin.Unit): kotlin.Unit
         CallsInPlace(block, EXACTLY_ONCE)
 
-    public final fun require(/*0*/ x: kotlin.Boolean): kotlin.Unit
-        Returns(WILDCARD) -> x
-
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
+