Adding check method to stdlib as detailed in KT-1530

libraries/stdlib/src/Preconditions.kt

@@ -21,7 +21,7 @@ inline fun assert(value:Boolean):Unit {
 * Throws an [[AssertionError]] with specified `message` if the `value` is false
 * and runtime assertions have been enabled on the JVM using the `-ea` JVM option.
 */
-inline fun assert<T>(value:Boolean, message:T) {
+inline fun assert(value:Boolean, message:Any) {
     if(Assertions._ENABLED) {
         if(!value) {
             throw AssertionError(message);
@@ -39,10 +39,30 @@ inline fun require(value:Boolean):Unit {
 }
 
 /**
-* Throws an [[IllegalArgumentException]] with specified `message` if the `value` is false.
-*/
-inline fun require<T>(value:Boolean, message:T) {
+ * Throws an [[IllegalArgumentException]] with specified `message` if the `value` is false.
+ */
+inline fun require(value:Boolean, message:Any):Unit {
     if(!value) {
         throw IllegalArgumentException(message.toString());
     }
 }
+
+/**
+ * Throws an [[IllegalStateException]] if the `value` is false.
+ */
+inline fun check(value:Boolean):Unit {
+    if(!value) {
+        throw IllegalStateException();
+    }
+}
+
+/**
+ * Throws an [[IllegalStateException]] with specified `message` if the `value` is false.
+ */
+inline fun check(value:Boolean, message:Any):Unit {
+    if(!value) {
+        throw IllegalStateException(message.toString());
+    }
+}
+
+

libraries/testlib/test/PreconditionsTest.kt

@@ -36,14 +36,66 @@ class PreconditionsTest() : TestCase() {
         }
     }
 
-//    // Not sure why the assert method is not being resolved.
-//    fun ignorePassingAssert() {
-//        assert(true)
+// TODO: uncomment when KT-1540 is resolved.
+//    fun testPassingCheck() {
+//        check1(true)
 //    }
 //
-//    fun ignoreFailingAssert() {
-//        failsWith<AssertionError> {
-//            assert(false)
+//    fun testFailingCheck() {
+//        val error = fails {
+//            check1(false)
+//        }
+//        if(error is IllegalStateException) {
+//            assertNull(error.getMessage())
+//        } else {
+//            fail("Invalid exception type: "+error)
+//        }
+//    }
+//
+//    fun testPassingCheckWithMessage() {
+//        check2(true, "Hello")
+//    }
+//
+//    fun testFailingCheckWithMessage() {
+//        val error = fails {
+//            check2(false, "Hello")
+//        }
+//        if(error is IllegalStateException) {
+//            assertEquals("Hello", error.getMessage())
+//        } else {
+//            fail("Invalid exception type: "+error)
+//        }
+//    }
+
+
+// TODO: uncomment when KT-1540 is resolved.
+//    fun testPassingAssert() {
+//        assert1(true)
+//    }
+//
+//    fun testFailingAssert() {
+//        val error = fails {
+//            assert1(false)
+//        }
+//        if(error is IllegalStateException) {
+//            assertNull(error.getMessage())
+//        } else {
+//            fail("Invalid exception type: "+error)
+//        }
+//    }
+//
+//    fun testPassingAssertWithMessage() {
+//        assert2(true, "Hello")
+//    }
+//
+//    fun testFailingAssertWithMessage() {
+//        val error = fails {
+//            assert2(false, "Hello")
+//        }
+//        if(error is IllegalStateException) {
+//            assertEquals("Hello", error.getMessage())
+//        } else {
+//            fail("Invalid exception type: "+error)
 //        }
 //    }
 }