expression #

Checks if actual value satisfies the expected expression.

• Expression should contain $V to represent current value.
• Expression should be a valid JavaScript code.
• Expression should return a boolean.

Syntax #

expression(expr)
expression(input, expr)

Usage #

✅ Correct Usage #

// expression
expression('$V.length > 0');

// input and expression
expression('some string', '$V.length > 0');

Arguments #

> expression (code) #

Javascript code to run.

> input (any) #

Input to return while using in contract testing. It can be anything.

Examples #

Assertions #

In this example, we are asserting the response from random-user api. The results from the server are dynamic, so we are using the expression matcher in expectJsonMatch to validate the age.

• age should be greater than 0.

const { spec } = require('pactum');
const { expression } = require('pactum-matchers');

await spec()
  .get('https://randomuser.me/api')
  .expectJsonMatch({
    "results": [
      {
        "dob": {
          "age": expression(10, "$V > 0")
        }
      }
    ]
  });