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Public
Edited
Mar 12
Importers
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Libraries
tests = ({
successWithEnsure() {
return ensure(Math.PI > 3, Math.PI < 4);
},
// To fix this test, remove all errors and falsy values
failWithEnsure() {
ensure("foo", Math.PI < 3, true, false, undefined, new Error());
},
// Tests written with expect.js, see below
helloWorld() {
expect(typeof "hello").to.be("string");
},
// To fix this test, do basic math
"Fail with expect"() {
expect(1 + 1).to.be(3);
},
math: {
subtraction: [
() => {
expect(1 - 0).to.be(1);
},
() => {
expect(1 - 2).to.be(-1);
}
],
add: {
twoNumbers() {
expect(3 + 4).to.be(7);
}
}
},
more: [
() => {
expect(1 - 0).to.be(1);
},
() => {
expect(1 - 2).to.be(-1);
}
],
// async
async fetchSuccess(i, id) {
console.log("Logging...", i, id);
// For demo purposes, this only runs on first iteration (i === 0) when tests are repeated
// Otherwise, changing `repeat` in the slider below would trigger a lot of requests
if (!i) {
await fetch("https://jsonplaceholder.typicode.com/posts/1");
}
},
async fetch404(i) {
if (!i) {
const res = await fetch("https://jsonplaceholder.typicode.com/posts/999");
ensure(!res.ok, res.status === 404);
}
},
// This test will fail (due to browser restrictions)
async fetchError(i) {
if (!i) {
await fetch("http://url.that.fails");
}
},
// This is testing an expected error
async fetchErrorPass(i) {
if (!i) {
const failure = await fails(async () => {
await fetch("http://url.that.fails");
});
ensure(_.isError(failure.error), failure.errorName === "TypeError");
}
}
})
ensure(2 < 1)
ensure(1 < 2)
ensure(
Math.PI,
Math.PI > 3,
Math.PI < 4,
_.isPlainObject({}),
_.isArray([]),
_.isNumber(Date.now()),
_.isDate(new Date()),
_.isEqual({ foo: "bar" }, { foo: "bar" })
)
ensure(
1 < 2,
2 < 1,
Math.PI < 3,
true,
false,
undefined,
_.isNumber("Hello"),
new Error()
)
ensure(
results,
_.isPlainObject(results),
_.isArray(results.all),
_.isBoolean(run),
// If you set run to false with the toggle above, this will fail
run,
_.isFunction(inspect),
_.isFunction(ensure),
_.isFunction(expect),
// Being clever: use map to avoid repeating the same test function
...[
repeat,
results.testCount,
results.failCount,
results.successCount
].map(
_.isNumber
)
)
function fail(...args) {
throw Error(...args);
}
await fetch("http://url.that.fails")
// This will NOT throw an error, so your test will pass
fails(async () => {
await fetch("http://url.that.fails");
})
// This WILL throw an error and fail your test
fails(() => {
console.log("Foo")
})
{
const { error } = await fails(async () => {
await fetch("http://url.that.fails");
});
return ensure(
_.isError(error),
error.name === "TypeError",
error.message === "Failed to fetch"
);
}
ensure(Math.PI < 3)
inspect(Math.PI < 3)
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