Intro to BDD Syntax

Kyle Coberly

kylecoberly.com

Educator
Business Dork
Software Developer

Learning Objective:

Recall the 3 types of Chai particles

Test-First Development

TDD vs. BDD

assert.equal(sum(1, 1), 2)

expect(sum(1, 1)).to.equal(2)

System's Perspective

User's Perspective

What mindset does writing the test put you in?

Can non-technical people understand your assertions?

Chai

Assertion Library
Syntax for assert, expect, and should
Works with any test runner

expect Particles

Chainers
Assertions
Flags

const people = [{
	kyle: { name: "Kyle", height: 90 },
	dusing: { name: "Dusing", height: 100 },
}]
const tallestPerson = { name: "Dusing", height: 100 }

expect(getTallest(people)).to.deep.equal(tallestPerson)

Chainer

Assertion

Flag

Chainers

```
to, be
```
```
have, has
```
```
a, an
```
```
and, but
```

Assertions

```
equal
```
```
property
```
```
a, an
```
```
true, false, ok, exist
```
```
empty
```
```
members, keys
```
```
include
```
```
lengthOf
```

Flags

```
not 
```
```
deep
```
```
nested
```
```
ordered
```

expect(result).to.have.nested.property("key.nestedKey", "value")
expect(result).to.include("some sub string")
expect(result).to.have.keys(["key1", "key2"])
expect(result).to.have.all.members(["item 1", "item 2"])
expect(result).to.match(/[a-zA-Z]/)

expect(result).to.equal("some string")
expect(result).to.deep.equal({ message: "some string" })
expect(result).to.not.equal("some string")
expect(result).to.have.lengthOf(3)

Equality

Matching

Examples

Kyle Coberly

kylecoberly.com