diff --git a/libraries/stdlib/src/kotlin/test/Test.kt b/libraries/stdlib/src/kotlin/test/Test.kt
index b63a762e10c..d35700281d8 100644
--- a/libraries/stdlib/src/kotlin/test/Test.kt
+++ b/libraries/stdlib/src/kotlin/test/Test.kt
@@ -44,7 +44,7 @@ public fun <T> assertNotNull(actual: T?, message: String = ""): T {
     return actual!!
 }
 
-//TODO merge with next via default
+//TODO merge with next via default (currently inline functions do not support default values)
 /** Asserts that the expression is not null, with an optional message and a function block to process the not-null value */
 public inline fun <T, R> assertNotNull(actual: T?, block: (T) -> R) {
     assertNotNull(actual, "", block)
diff --git a/libraries/stdlib/test/ExceptionTest.kt b/libraries/stdlib/test/ExceptionTest.kt
index 07b7b2744a8..5481959a823 100644
--- a/libraries/stdlib/test/ExceptionTest.kt
+++ b/libraries/stdlib/test/ExceptionTest.kt
@@ -29,12 +29,11 @@ class ExceptionTest {
 
     fun assertPrintStackTraceStream(t: Throwable) {
         val byteBuffer = ByteArrayOutputStream()
-/*
-        // TODO compiler error
+
         PrintStream(byteBuffer).use {
             t.printStackTrace(it)
         }
-*/
+
         val stream = PrintStream(byteBuffer)
         stream.use {
             t.printStackTrace(stream)
diff --git a/libraries/stdlib/test/PreconditionsTest.kt b/libraries/stdlib/test/PreconditionsTest.kt
index 4ba0b97c93f..c88448050ff 100644
--- a/libraries/stdlib/test/PreconditionsTest.kt
+++ b/libraries/stdlib/test/PreconditionsTest.kt
@@ -33,7 +33,7 @@ class PreconditionsTest() {
 
     test fun failingRequireWithLazyMessage() {
         val error = failsWith(javaClass<IllegalArgumentException>()) {
-            require(false) {"Hello"}
+            require(false) { "Hello" }
         }
         assertEquals("Hello", error.getMessage())
     }
@@ -66,7 +66,7 @@ class PreconditionsTest() {
 
     test fun failingCheckWithLazyMessage() {
         val error = failsWith(javaClass<IllegalStateException>()) {
-            check(false) {"Hello"}
+            check(false) { "Hello" }
         }
         assertEquals("Hello", error.getMessage())
     }
@@ -105,16 +105,15 @@ class PreconditionsTest() {
         assertFalse(called)
     }
 
-    test fun failingAssert() {
-        val assertDefaultMessage = "Assertion failed"
 
+    test fun failingAssert() {
         val error = fails {
             assert(false)
         }
-        if(error is AssertionError) {
-            assertEquals(assertDefaultMessage, error.getMessage())
+        if (error is AssertionError) {
+            assertEquals("Assertion failed", error.getMessage())
         } else {
-            fail("Invalid exception type: "+error)
+            fail("Invalid exception type: " + error)
         }
     }
 
@@ -126,21 +125,21 @@ class PreconditionsTest() {
         val error = fails {
             assert(false, "Hello")
         }
-        if(error is AssertionError) {
+        if (error is AssertionError) {
             assertEquals("Hello", error.getMessage())
         } else {
-            fail("Invalid exception type: "+error)
+            fail("Invalid exception type: " + error)
         }
     }
 
     test fun failingAssertWithLazyMessage() {
         val error = fails {
-            assert(false) {"Hello"}
+            assert(false) { "Hello" }
         }
-        if(error is AssertionError) {
+        if (error is AssertionError) {
             assertEquals("Hello", error.getMessage())
         } else {
-            fail("Invalid exception type: "+error)
+            fail("Invalid exception type: " + error)
         }
     }
 }
\ No newline at end of file
diff --git a/libraries/stdlib/test/language/StringExpressionExampleTest.kt b/libraries/stdlib/test/language/StringExpressionExampleTest.kt
index 4f7bebbc7dd..8c1634d002a 100644
--- a/libraries/stdlib/test/language/StringExpressionExampleTest.kt
+++ b/libraries/stdlib/test/language/StringExpressionExampleTest.kt
@@ -30,7 +30,7 @@ fun productSnippet(product: Product) = "<li>${product.name}. Price : ${product.p
 
 
 class StringExpressionExampleTest : TestCase() {
-    val customer = Customer("James", arrayList(Product("Beer", 1.99), Product("Wine", 5.99)))
+    val customer = Customer("James", arrayListOf(Product("Beer", 1.99), Product("Wine", 5.99)))
 
     fun testExpressions(): Unit {
         println(customerTemplate(customer))
diff --git a/libraries/stdlib/test/regressions/Kt1617Test.kt b/libraries/stdlib/test/regressions/Kt1617Test.kt
index 4dade12a55f..f8c808fd239 100644
--- a/libraries/stdlib/test/regressions/Kt1617Test.kt
+++ b/libraries/stdlib/test/regressions/Kt1617Test.kt
@@ -9,7 +9,7 @@ import junit.framework.TestCase
 
 class Kt1617Test: TestCase() {
     fun testMapFunction() {
-        val coll: Collection<String> = arrayList("foo", "bar")
+        val coll: Collection<String> = arrayListOf("foo", "bar")
 
         val files =  coll.map{ File(it) }
 
diff --git a/libraries/stdlib/test/regressions/Kt1619Test.kt b/libraries/stdlib/test/regressions/Kt1619Test.kt
index f9881fe374e..5a8c357a497 100644
--- a/libraries/stdlib/test/regressions/Kt1619Test.kt
+++ b/libraries/stdlib/test/regressions/Kt1619Test.kt
@@ -1,16 +1,16 @@
 package regressions
 
 import junit.framework.TestCase
+import kotlin.test.expect
 
 class Kt1619Test: TestCase() {
 
-    fun doSomething(list: List<String?>): Boolean {
-        return list.size() > 0
+    fun doSomething(list: List<String?>): Int {
+        return list.size()
     }
 
     fun testCollectionNotNullCanBeUsedForNullables() {
-        val list: List<String> = arrayList("foo", "bar")
-        // TODO uncomment this line to reproduce KT-1619
-        // doSomething(list)
+        val list: List<String> = arrayListOf("foo", "bar")
+        expect(2) { doSomething(list) }
     }
 }
\ No newline at end of file