diff --git a/libraries/stdlib/test/collections/ArraysTest.kt b/libraries/stdlib/test/collections/ArraysTest.kt
index 7d4e2dcbaaf..588b6cba3c4 100644
--- a/libraries/stdlib/test/collections/ArraysTest.kt
+++ b/libraries/stdlib/test/collections/ArraysTest.kt
@@ -525,7 +525,7 @@ class ArraysTest {
         expect(0.toByte()) { byteArrayOf(3, 2, 1) reduce { a, b -> (a - b).toByte() } }
         expect(0.toShort()) { shortArrayOf(3, 2, 1) reduce { a, b -> (a - b).toShort() } }
 
-        assertTrue(fails {
+        assertTrue(assertFails {
             intArrayOf().reduce { a, b -> a + b }
         } is UnsupportedOperationException)
     }
@@ -541,7 +541,7 @@ class ArraysTest {
         expect(2.toByte()) { byteArrayOf(1, 2, 3) reduceRight { a, b -> (a - b).toByte() } }
         expect(2.toShort()) { shortArrayOf(1, 2, 3) reduceRight { a, b -> (a - b).toShort() } }
 
-        assertTrue(fails {
+        assertTrue(assertFails {
             intArrayOf().reduceRight { a, b -> a + b }
         } is UnsupportedOperationException)
     }
@@ -581,7 +581,7 @@ class ArraysTest {
         expect(listOf(false), { booleanArrayOf(true, false).drop(1) })
         expect(listOf('b'), { charArrayOf('a', 'b').drop(1) })
         expect(listOf("b"), { arrayOf("a", "b").drop(1) })
-        fails {
+        assertFails {
             listOf(2).drop(-1)
         }
     }
@@ -599,7 +599,7 @@ class ArraysTest {
         expect(listOf(true), { booleanArrayOf(true, false).dropLast(1) })
         expect(listOf('a'), { charArrayOf('a', 'b').dropLast(1) })
         expect(listOf("a"), { arrayOf("a", "b").dropLast(1) })
-        fails {
+        assertFails {
             listOf(1).dropLast(-1)
         }
     }
@@ -645,7 +645,7 @@ class ArraysTest {
         expect(listOf(true), { booleanArrayOf(true, false).take(1) })
         expect(listOf('a'), { charArrayOf('a', 'b').take(1) })
         expect(listOf("a"), { arrayOf("a", "b").take(1) })
-        fails {
+        assertFails {
             listOf(1).take(-1)
         }
     }
@@ -663,7 +663,7 @@ class ArraysTest {
         expect(listOf(false), { booleanArrayOf(true, false).takeLast(1) })
         expect(listOf('b'), { charArrayOf('a', 'b').takeLast(1) })
         expect(listOf("b"), { arrayOf("a", "b").takeLast(1) })
-        fails {
+        assertFails {
             listOf(1).takeLast(-1)
         }
     }
diff --git a/libraries/stdlib/test/collections/CollectionJVMTest.kt b/libraries/stdlib/test/collections/CollectionJVMTest.kt
index a88a902a8ca..89df44678b9 100644
--- a/libraries/stdlib/test/collections/CollectionJVMTest.kt
+++ b/libraries/stdlib/test/collections/CollectionJVMTest.kt
@@ -109,7 +109,7 @@ class CollectionJVMTest {
     }
 
     @test fun lastException() {
-        fails { linkedListOf<String>().last() }
+        assertFails { linkedListOf<String>().last() }
     }
 
     @test fun contains() {
diff --git a/libraries/stdlib/test/collections/CollectionTest.kt b/libraries/stdlib/test/collections/CollectionTest.kt
index c008aead52d..3b291962f30 100644
--- a/libraries/stdlib/test/collections/CollectionTest.kt
+++ b/libraries/stdlib/test/collections/CollectionTest.kt
@@ -163,7 +163,7 @@ class CollectionTest {
 
         //        TODO replace with more accurate version when KT-5987 will be fixed
         //        failsWith(javaClass<UnsupportedOperationException>()) {
-        fails {
+        assertFails {
             run { arrayListOf<Int>().reduce { a, b -> a + b } }
         }
     }
@@ -176,7 +176,7 @@ class CollectionTest {
 
         //        TODO replace with more accurate version when KT-5987 will be fixed
         //        failsWith(javaClass<UnsupportedOperationException>()) {
-        fails {
+        assertFails {
             run { arrayListOf<Int>().reduceRight { a, b -> a + b } }
         }
     }
@@ -302,7 +302,7 @@ class CollectionTest {
 
         //        TODO replace with more accurate version when KT-5987 will be fixed
         //        failsWith(javaClass<IllegalArgumentException>()) {
-        fails {
+        assertFails {
             // should throw an exception as we have a null
             hasNulls.requireNoNulls()
         }
@@ -346,7 +346,7 @@ class CollectionTest {
         assertEquals(listOf("foo", "bar"), coll.dropLast(1))
         assertEquals(listOf("foo"), coll.dropLast(2))
 
-        fails { coll.dropLast(-1) }
+        assertFails { coll.dropLast(-1) }
     }
 
     @test fun dropLastWhile() {
@@ -365,7 +365,7 @@ class CollectionTest {
         assertEquals(coll, coll.take(coll.size()))
         assertEquals(coll, coll.take(coll.size() + 1))
 
-        fails { coll.take(-1) }
+        assertFails { coll.take(-1) }
     }
 
     @test fun takeWhile() {
@@ -385,7 +385,7 @@ class CollectionTest {
         assertEquals(coll, coll.takeLast(coll.size()))
         assertEquals(coll, coll.takeLast(coll.size() + 1))
 
-        fails { coll.takeLast(-1) }
+        assertFails { coll.takeLast(-1) }
     }
 
     @test fun takeLastWhile() {
@@ -420,7 +420,7 @@ class CollectionTest {
         assertEquals("foo", data.first())
         assertEquals(15, listOf(15, 19, 20, 25).first())
         assertEquals('a', listOf('a').first())
-        fails { arrayListOf<Int>().first() }
+        assertFails { arrayListOf<Int>().first() }
     }
 
     @test fun last() {
@@ -428,7 +428,7 @@ class CollectionTest {
         assertEquals("bar", data.last())
         assertEquals(25, listOf(15, 19, 20, 25).last())
         assertEquals('a', listOf('a').last())
-        fails { arrayListOf<Int>().last() }
+        assertFails { arrayListOf<Int>().last() }
     }
 
     @test fun subscript() {
@@ -437,7 +437,7 @@ class CollectionTest {
         assertEquals("bar", list[1])
 
         // lists throw an exception if out of range
-        fails {
+        assertFails {
             assertEquals(null, list[2])
         }
 
@@ -446,7 +446,7 @@ class CollectionTest {
         list[1] = "thing"
 
         // lists don't allow you to set past the end of the list
-        fails {
+        assertFails {
             list[2] = "works"
         }
 
diff --git a/libraries/stdlib/test/collections/ComparisonDSL.kt b/libraries/stdlib/test/collections/ComparisonDSL.kt
index eade428e95d..563132e7789 100644
--- a/libraries/stdlib/test/collections/ComparisonDSL.kt
+++ b/libraries/stdlib/test/collections/ComparisonDSL.kt
@@ -20,8 +20,8 @@ public class CompareContext<out T>(public val expected: T, public val actual: T)
     }
 
     private fun assertFailEquals(expected: () -> Unit, actual: () -> Unit) {
-        val expectedFail = fails(expected)
-        val actualFail = fails(actual)
+        val expectedFail = assertFails(expected)
+        val actualFail = assertFails(actual)
         //assertEquals(expectedFail != null, actualFail != null)
         assertTypeEquals(expectedFail, actualFail)
     }
diff --git a/libraries/stdlib/test/collections/IterableTests.kt b/libraries/stdlib/test/collections/IterableTests.kt
index 62d3ca57a2c..a25a22724c3 100644
--- a/libraries/stdlib/test/collections/IterableTests.kt
+++ b/libraries/stdlib/test/collections/IterableTests.kt
@@ -56,9 +56,9 @@ abstract class OrderedIterableTests<T : Iterable<String>>(data: T, empty: T) : I
     fun elementAt() {
         expect("foo") { data.elementAt(0) }
         expect("bar") { data.elementAt(1) }
-        fails { data.elementAt(2) }
-        fails { data.elementAt(-1) }
-        fails { empty.elementAt(0) }
+        assertFails { data.elementAt(2) }
+        assertFails { data.elementAt(-1) }
+        assertFails { empty.elementAt(0) }
 
         expect("foo") { data.elementAtOrElse(0, {""} )}
         expect("zoo") { data.elementAtOrElse(-1, { "zoo" })}
@@ -72,10 +72,10 @@ abstract class OrderedIterableTests<T : Iterable<String>>(data: T, empty: T) : I
     @Test
     fun first() {
         expect("foo") { data.first() }
-        fails {
+        assertFails {
             data.first { it.startsWith("x") }
         }
-        fails {
+        assertFails {
             empty.first()
         }
         expect("foo") { data.first { it.startsWith("f") } }
@@ -93,10 +93,10 @@ abstract class OrderedIterableTests<T : Iterable<String>>(data: T, empty: T) : I
     @Test
     fun last() {
         assertEquals("bar", data.last())
-        fails {
+        assertFails {
             data.last { it.startsWith("x") }
         }
-        fails {
+        assertFails {
             empty.last()
         }
         expect("foo") { data.last { it.startsWith("f") } }
@@ -190,11 +190,11 @@ abstract class IterableTests<T : Iterable<String>>(val data: T, val empty: T) {
 
     @Test
     fun single() {
-        fails { data.single() }
-        fails { empty.single() }
+        assertFails { data.single() }
+        assertFails { empty.single() }
         expect("foo") { data.single { it.startsWith("f") } }
         expect("bar") { data.single { it.startsWith("b") } }
-        fails {
+        assertFails {
             data.single { it.length() == 3 }
         }
     }
diff --git a/libraries/stdlib/test/collections/ListSpecificTest.kt b/libraries/stdlib/test/collections/ListSpecificTest.kt
index 16d390d0344..1ce7d7c9285 100644
--- a/libraries/stdlib/test/collections/ListSpecificTest.kt
+++ b/libraries/stdlib/test/collections/ListSpecificTest.kt
@@ -35,9 +35,9 @@ class ListSpecificTest {
     fun getOr() {
         expect("foo") { data.get(0) }
         expect("bar") { data.get(1) }
-        fails { data.get(2) }
-        fails { data.get(-1) }
-        fails { empty.get(0) }
+        assertFails { data.get(2) }
+        assertFails { data.get(-1) }
+        assertFails { empty.get(0) }
 
         expect("foo") { data.getOrElse(0, {""} )}
         expect("zoo") { data.getOrElse(-1, { "zoo" })}
diff --git a/libraries/stdlib/test/collections/MapJVMTest.kt b/libraries/stdlib/test/collections/MapJVMTest.kt
index f6908d42daa..44740e5dc81 100644
--- a/libraries/stdlib/test/collections/MapJVMTest.kt
+++ b/libraries/stdlib/test/collections/MapJVMTest.kt
@@ -43,7 +43,7 @@ class MapJVMTest {
     @test fun getOrPutFailsOnConcurrentMap() {
         val map = ConcurrentHashMap<String, Int>()
 
-        fails {
+        assertFails {
             map.getOrPut("x") { 1 }
         }
         expect(1) {
diff --git a/libraries/stdlib/test/collections/MapTest.kt b/libraries/stdlib/test/collections/MapTest.kt
index 492162f42f1..c2ced15078f 100644
--- a/libraries/stdlib/test/collections/MapTest.kt
+++ b/libraries/stdlib/test/collections/MapTest.kt
@@ -1,10 +1,7 @@
 package test.collections
 
 import java.util.*
-import kotlin.test.assertEquals
-import kotlin.test.assertFalse
-import kotlin.test.assertTrue
-import kotlin.test.fails
+import kotlin.test.*
 import org.junit.Test as test
 
 class MapTest {
@@ -25,7 +22,7 @@ class MapTest {
 
     @test fun getOrImplicitDefault() {
         val data: MutableMap<String, Int> = hashMapOf("bar" to 1)
-        assertTrue(fails { data.getOrImplicitDefault("foo") } is NoSuchElementException)
+        assertTrue(assertFails { data.getOrImplicitDefault("foo") } is NoSuchElementException)
         assertEquals(1, data.getOrImplicitDefault("bar"))
 
         val mutableWithDefault = data.withDefault { 42 }
diff --git a/libraries/stdlib/test/collections/SequenceTest.kt b/libraries/stdlib/test/collections/SequenceTest.kt
index a4d860be004..2d7baa14185 100644
--- a/libraries/stdlib/test/collections/SequenceTest.kt
+++ b/libraries/stdlib/test/collections/SequenceTest.kt
@@ -39,7 +39,7 @@ public class SequenceTest {
 
         val sequenceWithNulls = sequenceOf("foo", null, "bar")
         val notNull2 = sequenceWithNulls.requireNoNulls() // shouldn't fail yet
-        fails {
+        assertFails {
             // should throw an exception as we have a null
             notNull2.toList()
         }
@@ -213,7 +213,7 @@ public class SequenceTest {
         val list = sequence.toList()
         assertEquals(listOf(2, 1, 0), list)
 
-        fails {
+        assertFails {
             sequence.toList()
         }
     }
@@ -231,7 +231,7 @@ public class SequenceTest {
         val iterator = list.iterator()
         val sequence = iterator.asSequence()
         assertEquals(list, sequence.toList())
-        fails {
+        assertFails {
             sequence.toList()
         }
     }
@@ -244,7 +244,7 @@ public class SequenceTest {
         val oneTime = sequence.constrainOnce()
         oneTime.toList()
         assertTrue("should fail with IllegalStateException") {
-            fails {
+            assertFails {
                 oneTime.toList()
             } is IllegalStateException
         }
diff --git a/libraries/stdlib/test/iterators/IteratorsTest.kt b/libraries/stdlib/test/iterators/IteratorsTest.kt
index 69618367541..95b40542258 100644
--- a/libraries/stdlib/test/iterators/IteratorsTest.kt
+++ b/libraries/stdlib/test/iterators/IteratorsTest.kt
@@ -2,8 +2,8 @@ package iterators
 
 import kotlin.test.assertEquals
 import org.junit.Test as test
-import kotlin.test.fails
 import java.util.ArrayList
+import kotlin.test.assertFails
 
 fun fibonacci(): Sequence<Int> {
     // fibonacci terms
@@ -71,7 +71,7 @@ class IteratorsTest {
 
         val iterWithNulls = arrayListOf("foo", null, "bar").asSequence()
         val notNull2 = iterWithNulls.requireNoNulls()
-        fails {
+        assertFails {
             // should throw an exception as we have a null
             notNull2.toList()
         }
diff --git a/libraries/stdlib/test/language/RangeTest.kt b/libraries/stdlib/test/language/RangeTest.kt
index 0a428b1c96f..1f40847f11b 100644
--- a/libraries/stdlib/test/language/RangeTest.kt
+++ b/libraries/stdlib/test/language/RangeTest.kt
@@ -33,7 +33,7 @@ public class RangeTest {
         assertTrue(9 in openRange)
         assertFalse(10 in openRange)
 
-        assertTrue(fails { 1 until Int.MIN_VALUE } is IllegalArgumentException)
+        assertTrue(assertFails { 1 until Int.MIN_VALUE } is IllegalArgumentException)
     }
 
     @test fun byteRange() {
@@ -66,7 +66,7 @@ public class RangeTest {
         assertTrue(9.toByte() in openRange)
         assertFalse(10.toByte() in openRange)
 
-        assertTrue(fails { 0.toByte() until Byte.MIN_VALUE } is IllegalArgumentException)
+        assertTrue(assertFails { 0.toByte() until Byte.MIN_VALUE } is IllegalArgumentException)
 
     }
 
@@ -99,7 +99,7 @@ public class RangeTest {
         assertTrue(9.toShort() in openRange)
         assertFalse(10.toShort() in openRange)
 
-        assertTrue(fails { 0.toShort() until Short.MIN_VALUE } is IllegalArgumentException)
+        assertTrue(assertFails { 0.toShort() until Short.MIN_VALUE } is IllegalArgumentException)
     }
 
     @test fun longRange() {
@@ -131,7 +131,7 @@ public class RangeTest {
         assertTrue(9L in openRange)
         assertFalse(10L in openRange)
 
-        assertTrue(fails { 0L until Long.MIN_VALUE } is IllegalArgumentException)
+        assertTrue(assertFails { 0L until Long.MIN_VALUE } is IllegalArgumentException)
 
     }
 
@@ -156,7 +156,7 @@ public class RangeTest {
         assertTrue('Y' in openRange)
         assertFalse('Z' in openRange)
 
-        assertTrue(fails { 'A' until '\u0000' } is IllegalArgumentException)
+        assertTrue(assertFails { 'A' until '\u0000' } is IllegalArgumentException)
     }
 
     @test fun doubleRange() {
diff --git a/libraries/stdlib/test/numbers/CoercionTest.kt b/libraries/stdlib/test/numbers/CoercionTest.kt
index c8ee596a606..1ea7d0db96d 100644
--- a/libraries/stdlib/test/numbers/CoercionTest.kt
+++ b/libraries/stdlib/test/numbers/CoercionTest.kt
@@ -36,8 +36,8 @@ class CoercionTest {
             assertTrue((value coerceIn range) in range)
         }
 
-        fails { 1.coerceIn(1, 0) }
-        fails { 1.coerceIn(1..0) }
+        assertFails { 1.coerceIn(1, 0) }
+        assertFails { 1.coerceIn(1..0) }
     }
 
     @Test
@@ -59,8 +59,8 @@ class CoercionTest {
             assertTrue((value coerceIn range) in range)
         }
 
-        fails { 1L.coerceIn(1L, 0L) }
-        fails { 1L.coerceIn(1L..0L) }
+        assertFails { 1L.coerceIn(1L, 0L) }
+        assertFails { 1L.coerceIn(1L..0L) }
 
     }
 
@@ -83,8 +83,8 @@ class CoercionTest {
             assertTrue((value coerceIn range) in range)
         }
 
-        fails { 1.0.coerceIn(1.0, 0.0) }
-        fails { 1.0.coerceIn(1.0..0.0) }
+        assertFails { 1.0.coerceIn(1.0, 0.0) }
+        assertFails { 1.0.coerceIn(1.0..0.0) }
     }
 
     @Test
@@ -111,8 +111,8 @@ class CoercionTest {
             assertTrue((value coerceIn range) in range)
         }
 
-        fails { v[1].coerceIn(v[1], v[0]) }
-        fails { v[1].coerceIn(v[1]..v[0]) }
+        assertFails { v[1].coerceIn(v[1], v[0]) }
+        assertFails { v[1].coerceIn(v[1]..v[0]) }
     }
 }
 
diff --git a/libraries/stdlib/test/properties/delegation/MapAccessorsTest.kt b/libraries/stdlib/test/properties/delegation/MapAccessorsTest.kt
index 276cfee5547..a4f4336b018 100644
--- a/libraries/stdlib/test/properties/delegation/MapAccessorsTest.kt
+++ b/libraries/stdlib/test/properties/delegation/MapAccessorsTest.kt
@@ -25,7 +25,7 @@ class ValByMapExtensionsTest {
         assertEquals("default", e)
         assertEquals(1, i)
         assertEquals(1.0, x)
-        assertTrue(fails { d } is NoSuchElementException)
+        assertTrue(assertFails { d } is NoSuchElementException)
     }
 }
 
@@ -60,7 +60,7 @@ class VarByMapExtensionsTest {
         map["a"] = null
         a // fails { a } // does not fail due to KT-8135
 
-        assertTrue(fails { d } is NoSuchElementException)
+        assertTrue(assertFails { d } is NoSuchElementException)
         map["d"] = null
         assertEquals(null, d)
     }
diff --git a/libraries/stdlib/test/text/StringJVMTest.kt b/libraries/stdlib/test/text/StringJVMTest.kt
index 205031bbcf2..3f9f234dfa0 100644
--- a/libraries/stdlib/test/text/StringJVMTest.kt
+++ b/libraries/stdlib/test/text/StringJVMTest.kt
@@ -68,13 +68,13 @@ class StringJVMTest {
         // deprecation replacement equivalence
         assertEquals("\\d".toPattern().split(s).toList(), s.split("\\d".toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray().toList())
 
-        fails {
+        assertFails {
             s.split(isDigit, -1)
         }
     }
 
     @test fun repeat() {
-        fails{ "foo".repeat(-1) }
+        assertFails { "foo".repeat(-1) }
         assertEquals("", "foo".repeat(0))
         assertEquals("foo", "foo".repeat(1))
         assertEquals("foofoo", "foo".repeat(2))
@@ -269,7 +269,7 @@ class StringJVMTest {
     @test fun drop() {
         val data = "abcd1234"
         assertEquals("d1234", data.drop(3))
-        fails {
+        assertFails {
             data.drop(-2)
         }
         assertEquals("", data.drop(data.length() + 5))
@@ -285,7 +285,7 @@ class StringJVMTest {
     @test fun take() {
         val data = "abcd1234"
         assertEquals("abc", data.take(3))
-        fails {
+        assertFails {
             data.take(-7)
         }
         assertEquals(data, data.take(data.length() + 42))
@@ -351,10 +351,10 @@ class StringJVMTest {
         assertEquals("baD", builder.slice(5 downTo 3))
         assertEquals("aDAB", builder.slice(iter))
 
-        fails {
+        assertFails {
             "abc".slice(listOf(1,4))
         }
-        fails {
+        assertFails {
             builder.slice(listOf(10))
         }
     }
diff --git a/libraries/stdlib/test/text/StringTest.kt b/libraries/stdlib/test/text/StringTest.kt
index 661be46f68b..ada215d34e9 100644
--- a/libraries/stdlib/test/text/StringTest.kt
+++ b/libraries/stdlib/test/text/StringTest.kt
@@ -1,9 +1,6 @@
 package test.text
 
-import kotlin.test.assertEquals
-import kotlin.test.assertFalse
-import kotlin.test.assertTrue
-import kotlin.test.fails
+import kotlin.test.*
 import org.junit.Test as test
 
 // could not be local inside isEmptyAndBlank, because non-toplevel declarations is not yet supported for JS
@@ -146,10 +143,10 @@ class StringTest {
         val s = "sample text"
         assertEquals("sa??e text", s.replaceRange(2, 5, "??"))
         assertEquals("sa?? text", s.replaceRange(2..5, "??"))
-        fails {
+        assertFails {
             s.replaceRange(5..2, "??")
         }
-        fails {
+        assertFails {
             s.replaceRange(5, 2, "??")
         }
 
@@ -298,7 +295,7 @@ class StringTest {
         assertEquals("s", "s".padStart(1))
         assertEquals("  ", "".padStart(2))
         assertEquals("--s", "s".padStart(3, '-'))
-        fails {
+        assertFails {
             "s".padStart(-1)
         }
     }
@@ -308,7 +305,7 @@ class StringTest {
         assertEquals("s", "s".padEnd(1))
         assertEquals("  ", "".padEnd(2))
         assertEquals("s--", "s".padEnd(3, '-'))
-        fails {
+        assertFails {
             "s".padEnd(-1)
         }
     }
diff --git a/libraries/stdlib/test/utils/TODOTest.kt b/libraries/stdlib/test/utils/TODOTest.kt
index 04ceff12aa1..b066020847f 100644
--- a/libraries/stdlib/test/utils/TODOTest.kt
+++ b/libraries/stdlib/test/utils/TODOTest.kt
@@ -27,11 +27,11 @@ private class PartiallyImplementedClass {
 
 class TODOTest {
     private fun assertNotImplemented(block: () -> Unit) {
-        assertTrue(fails(block) is NotImplementedError)
+        assertTrue(assertFails(block) is NotImplementedError)
     }
 
     private fun assertNotImplementedWithMessage(message: String, block: () -> Unit) {
-        val e = fails(block)
+        val e = assertFails(block)
         assertTrue(e is NotImplementedError)
         assertTrue(message in e!!.getMessage()!!)
     }