# Extending Mocks

When you desire a more refined dataset from your mocks you have two levels of control you can exert:

  1. Named Contexts -- you can tag properties in your model to a known "type"
  2. Bespoke Handling -- you can write your own function for a given property in your model

Let's explore each of these separately.

# Named Contexts

In the auto-mocking section we saw how a property named name would be automatically populated with a random name. What if you had a property called fathersName? Well that would NOT automatically be given a name but rather just a random string. This is a good example of where named contexts can be leveraged to give the fathersName property the same treatment as name.

Here's how we'd do that:

export class Person extends Model {
  @property public name: string;
  @property @mock("name") public fathersName: string;

with this simple addition you've told the mocking engine that the property fathersName should be treated as a name. Pretty cool right?

So the obvious next question is ... what named properties are there? Glad you're there keeping me honest. So the answer is:

  • name
    • firstName
    • lastName
  • company
    • companyName
    • catchPhrase
  • address
    • streetName
    • streetAddress
    • city
    • county
    • state
    • stateAbbr
    • zipCode
    • country
    • countryCode
  • latitude
  • longitude
  • gender
  • date (alias for dateRecent)
    • datePast (or datePastString for string return instead of Date)
    • dateFuture (or dateFutureString for string return instead of Date)
    • dateRecent (or dateRecentString for string return instead of Date)
    • dateSoon (or dateSoonString for string return instead of Date)
  • images
    • avatar
    • imageAnimal
    • imagePerson
    • imageNature
    • imageTransport
  • phoneNumber
  • lorem
    • word
    • words
    • sentence
    • slug
    • paragraph
    • paragraphs
    • url

All you need to do is choose any of the above and add the @mock([named tag]) as a modifier to the property. There are a few more named contexts which take additional params:

  • number - mock("number", { min: 0, max: 1000, precision: 0 })
    • allows you to get a number of a any combination of a stated min, max, or precision.
    • if no parameter value is stated then the number will be between 1 and 100
    • if you want a number with two decimal places to the right then you'd set precision to .01
  • price -mock("price", { min: 10, max: 1000, symbol: "£" })
    • the precision defaults to 2
    • The currency symbol default to "$" but can be set to whatever character you please
    • by default the "cents" component is always 0 but you can set it to a variant amount with {variableCents}: true}; when this is set it distributes 40% of values to 0 cents, 30% to 99 cents, and the remaining 30% to a random number
  • random - @mock("random", ...arrayOfThings)
    • using a normal distribution, chooses one of the array items each time
  • sequence = @mock("shuffle", ...arrayOfThings)
    • sequentially applies each array item and then repeats if none are left
  • distribution = @mock("distribution", [40, "male"], [50, "female"], [10, "other])
    • similar to random but it allows you to state the percentage chance of each possible outcome
  • placeImage - @mock("placeImage", width, heigh, type)
    • types are "animals", "architecture", "people", "nature", "people", and "tech". Default type is "any"
  • placeHolder - @mock("placeHolder", size, backgroundColor, textColor)
    • size can be a single number like "300" which represents both height and width or it can separate height from width with "300x100"
    • backgroundColor and textColor are hex values like FFFFFF (white), 0000FF (blue), etc.

# Bespoke Handling

The named contexts should take you a long way but sometimes not to the finish line. In these situations you can drop out of "configuration" and into code:

const myBespokeHandler: IMockHelper = (context) => {
  return context.faker...

export class Person extends Model {
  @property name: string;
  @property @mock(myBespokeHandler) fathersName: string;
Last Updated: 7/13/2019, 12:18:01 AM