blob: 78c486358a0a305d2f913cddb2fd476671bd961e [file] [log] [blame]
// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// @dart = 2.9
import "package:expect/expect.dart";
main() {
var assertsEnabled = false;
assert((assertsEnabled = true));
if (!assertsEnabled) return;
// TODO(rnystrom): Test cases where the first argument to assert() is a
// function.
testAssertFails();
testAssertDoesNotFail();
testNullMessage();
testDoesNotEvaluateMessageIfAssertSucceeds();
testMessageExpressionThatThrows();
testCallsToStringOnMessageLazily();
}
/// A class with a custom toString() that tracks when it is called.
class ToString {
bool calledToString = false;
String toString() {
calledToString = true;
return "toString!";
}
}
testAssertFails() {
try {
assert(false, "Oops");
Expect.fail("Assert should throw.");
} catch (e) {
Expect.isTrue(e.toString().contains("Oops"));
}
}
testAssertDoesNotFail() {
try {
assert(true, "Oops");
} catch (e) {
Expect.fail("Assert should not throw.");
}
}
testNullMessage() {
try {
assert(false, null);
Expect.fail("Assert should throw.");
} catch (e) {
Expect.isTrue(e.toString().contains("is not true"));
}
}
testDoesNotEvaluateMessageIfAssertSucceeds() {
try {
var evaluated = false;
assert(true, evaluated = true);
Expect.isFalse(evaluated);
} catch (e) {
Expect.fail("Assert should not throw.");
}
}
testMessageExpressionThatThrows() {
try {
assert(false, throw "dang");
Expect.fail("Should throw");
} catch (e) {
Expect.equals(e, "dang");
}
}
testCallsToStringOnMessageLazily() {
var toString = new ToString();
try {
assert(false, toString);
Expect.fail("Assert should throw.");
} catch (e) {
Expect.isFalse(toString.calledToString);
Expect.isTrue(e.toString().contains("Instance of 'ToString'"));
Expect.isFalse(toString.calledToString);
}
}