diff --git a/kotlin-power-assert-plugin/src/main/kotlin/com/bnorm/power/PowerAssertCallTransformer.kt b/kotlin-power-assert-plugin/src/main/kotlin/com/bnorm/power/PowerAssertCallTransformer.kt
index f3a5ebdb8fb..e9367f5c037 100644
--- a/kotlin-power-assert-plugin/src/main/kotlin/com/bnorm/power/PowerAssertCallTransformer.kt
+++ b/kotlin-power-assert-plugin/src/main/kotlin/com/bnorm/power/PowerAssertCallTransformer.kt
@@ -229,11 +229,11 @@ class PowerAssertCallTransformer(
   private fun isStringSupertype(type: IrType): Boolean =
     context.irBuiltIns.stringType.isSubtypeOf(type, context.irBuiltIns)
 
-  private fun IrType.isAssignableTo(type: IrType): Boolean =
-    isSubtypeOf(type, context.irBuiltIns) ||
-      ((type.classifierOrNull as? IrTypeParameterSymbol)?.owner?.superTypes?.all {
-        isSubtypeOf(it, context.irBuiltIns)
-      } ?: false)
+  private fun IrType.isAssignableTo(type: IrType): Boolean {
+    if (isSubtypeOf(type, context.irBuiltIns)) return true
+    val superTypes = (type.classifierOrNull as? IrTypeParameterSymbol)?.owner?.superTypes
+    return superTypes != null && superTypes.all { isSubtypeOf(it, context.irBuiltIns) }
+  }
 
   private fun MessageCollector.info(expression: IrElement, message: String) {
     report(expression, CompilerMessageSeverity.INFO, message)
diff --git a/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/AssertBooleanTest.kt b/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/AssertBooleanTest.kt
index 786287f45d0..ade3f26a4de 100644
--- a/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/AssertBooleanTest.kt
+++ b/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/AssertBooleanTest.kt
@@ -2,24 +2,23 @@ package com.bnorm.power
 
 import org.jetbrains.kotlin.name.FqName
 import org.junit.Test
-import kotlin.test.assertEquals
 
 class AssertBooleanTest {
   @Test
   fun `test assertTrue transformation`() {
     assertMessage(
       """
-import kotlin.test.assertTrue
-
-fun main() {
-  assertTrue(1 != 1)
-}""",
+      import kotlin.test.assertTrue
+      
+      fun main() {
+        assertTrue(1 != 1)
+      }""",
       """
-Assertion failed
-assertTrue(1 != 1)
-             |
-             false
-""".trimIndent(),
+      Assertion failed
+      assertTrue(1 != 1)
+                   |
+                   false
+      """.trimIndent(),
       PowerAssertComponentRegistrar(setOf(FqName("kotlin.test.assertTrue")))
     )
   }
@@ -28,17 +27,17 @@ assertTrue(1 != 1)
   fun `test assertFalse transformation`() {
     assertMessage(
       """
-import kotlin.test.assertFalse
-
-fun main() {
-  assertFalse(1 == 1)
-}""",
+      import kotlin.test.assertFalse
+      
+      fun main() {
+        assertFalse(1 == 1)
+      }""",
       """
-Assertion failed
-assertFalse(1 == 1)
-              |
-              true
-""".trimIndent(),
+      Assertion failed
+      assertFalse(1 == 1)
+                    |
+                    true
+      """.trimIndent(),
       PowerAssertComponentRegistrar(setOf(FqName("kotlin.test.assertFalse")))
     )
   }
diff --git a/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/DebugFunctionTest.kt b/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/DebugFunctionTest.kt
index 34edaa0d940..b77dad7cb41 100644
--- a/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/DebugFunctionTest.kt
+++ b/kotlin-power-assert-plugin/src/test/kotlin/com/bnorm/power/DebugFunctionTest.kt
@@ -12,9 +12,11 @@ import kotlin.test.assertEquals
 class DebugFunctionTest {
   @Test
   fun `debug function transformation`() {
-    val actual = executeMainDebug("""
+    val actual = executeMainDebug(
+      """
       dbg(1 + 2 + 3)
-    """.trimIndent())
+      """.trimIndent()
+    )
     assertEquals(
       """
       dbg(1 + 2 + 3)
@@ -27,9 +29,11 @@ class DebugFunctionTest {
   }
   @Test
   fun `debug function transformation with message`() {
-    val actual = executeMainDebug("""
+    val actual = executeMainDebug(
+      """
       dbg(1 + 2 + 3, "Message:")
-    """.trimIndent())
+      """.trimIndent()
+    )
     assertEquals(
       """
       Message:
diff --git a/sample/src/commonTest/kotlin/com/bnorm/power/PowerAssertTest.kt b/sample/src/commonTest/kotlin/com/bnorm/power/PowerAssertTest.kt
index 8e374f9396e..c0231ff33de 100644
--- a/sample/src/commonTest/kotlin/com/bnorm/power/PowerAssertTest.kt
+++ b/sample/src/commonTest/kotlin/com/bnorm/power/PowerAssertTest.kt
@@ -130,7 +130,8 @@ class PowerAssertTest {
             |        |
             |        Jane
             Hello, Jane
-      """.trimIndent())
+      """.trimIndent()
+    )
   }
 
   @Test
@@ -146,6 +147,7 @@ class PowerAssertTest {
             |        |
             |        Jane
             Hello, Jane
-      """.trimIndent())
+      """.trimIndent()
+    )
   }
 }