Tests tab and pm.test() in Postman - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the test result of this Postman test script?

Consider this Postman test script in the Tests tab:

pm.test("Status code is 200", function () {
    pm.response.to.have.status(200);
});
pm.test("Response time is less than 500ms", function () {
    pm.expect(pm.response.responseTime).to.be.below(500);
});

Assuming the response status is 200 and response time is 450ms, what will be the test execution result?

Postman

pm.test("Status code is 200", function () {
    pm.response.to.have.status(200);
});
pm.test("Response time is less than 500ms", function () {
    pm.expect(pm.response.responseTime).to.be.below(500);
});

A Both tests pass

B First test fails, second test passes

C First test passes, second test fails

D Both tests fail

💡 Hint

Check the status code and response time conditions carefully.

The first test checks if the status code is exactly 200, which it is. The second test checks if the response time is below 500ms, which 450ms satisfies. So both tests pass.

❓ assertion

intermediate

Which pm.test assertion correctly checks if JSON response has a key 'userId'?

You want to write a test in Postman to verify that the JSON response body contains the key 'userId'. Which pm.test assertion below will correctly do this?

A pm.test("Response has userId", () => { pm.expect(pm.response.json().userId).to.exist; });

B pm.test("Response has userId", () => { pm.expect(pm.response.json()).to.have.property('userId'); });

C pm.test("Response has userId", () => { pm.expect(pm.response.json().has('userId')).to.be.true; });

D pm.test("Response has userId", () => { pm.expect(pm.response.json().includes('userId')).to.be.true; });

💡 Hint

Check which method correctly tests for a property in an object.

Option B uses the correct Chai assertion to check if the JSON object has the property 'userId'. Option B uses 'to.exist' on a value which may fail if userId is falsy. Option B and D use invalid methods for objects.

🔧 Debug

advanced

Why does this pm.test fail with a TypeError?

Look at this Postman test code:

pm.test("Check user name", function() {
    let jsonData = pm.response.json;
    pm.expect(jsonData.name).to.eql("Alice");
});

What causes the TypeError during test execution?

Postman

pm.test("Check user name", function() {
    let jsonData = pm.response.json;
    pm.expect(jsonData.name).to.eql("Alice");
});

A The test function is missing a return statement

B pm.expect is not defined in the Tests tab

C pm.response.json is a function and needs to be called as pm.response.json()

D The property 'name' does not exist in the response

💡 Hint

Check how to correctly get JSON data from the response.

pm.response.json is a function that returns the parsed JSON body. Without parentheses, jsonData is assigned the function itself, causing a TypeError when accessing .name.

🧠 Conceptual

advanced

What is the purpose of pm.test() in Postman?

Select the best description of what pm.test() does in Postman test scripts.

A It sends the HTTP request to the server and waits for the response.

B It automatically retries the request if the test fails.

C It logs the response body to the Postman console for debugging.

D It defines a test case with a name and a function containing assertions to validate the response.

💡 Hint

Think about how tests are structured in Postman.

pm.test() wraps assertions inside a named test case. It does not send requests, log output, or retry requests.

❓ framework

expert

Which option correctly waits for a response before running pm.test assertions in Postman?

You want to write a test script that runs assertions only after the response is fully received. Which code snippet correctly ensures this in Postman?

A pm.sendRequest(request, function (err, res) { pm.test("Status is 200", () => { pm.expect(res).to.have.property('code', 200); }); });

B pm.test("Status is 200", () => { pm.expect(pm.response.code).to.equal(200); });

C pm.response.on('complete', () => { pm.test("Status is 200", () => { pm.expect(pm.response.code).to.equal(200); }); });

D pm.waitForResponse(() => { pm.test("Status is 200", () => { pm.expect(pm.response.code).to.equal(200); }); });

💡 Hint

Check which method uses a callback after the request completes.

Option A uses pm.sendRequest with a callback that runs tests after the response arrives. Option A runs tests immediately on the current response. Options C and D use non-existent event or method.

Practice

1. What is the main purpose of the pm.test() function in Postman's Tests tab?

easy

A. To define a named test and run assertions on the API response

B. To send an API request to the server

C. To format the API response data

D. To create a new collection in Postman

Solution

1. Step 1: Understand the role of pm.test()

   The pm.test() function is used to define a test with a descriptive name and a function that contains checks or assertions.

2. Step 2: Identify what pm.test() does in the Tests tab

   It runs the test function to verify if the API response meets expected conditions, helping automate validation.

3. Final Answer:

   To define a named test and run assertions on the API response -> Option A

4. Quick Check:

   pm.test() defines tests = A [OK]

Hint: pm.test() names and runs checks on responses [OK]

Common Mistakes:

• Confusing pm.test() with sending requests
• Thinking pm.test() formats data
• Assuming pm.test() creates collections

2. Which of the following is the correct syntax to write a test in Postman that checks if the response status code is 200?

easy

A. pm.test('Status code is 200', function { pm.response.status == 200 });

B. pm.test('Status code is 200', () => pm.response.to.have.status(200));

C. pm.test('Status code is 200', pm.response.status === 200);

D. pm.test('Status code is 200', () => pm.response.status = 200);

Solution

1. Step 1: Review correct pm.test() syntax

   The correct syntax uses a test name string and a function with assertions inside, like an arrow function.

2. Step 2: Check assertion method for status code

   Using pm.response.to.have.status(200) is the proper way to assert status code 200.

3. Final Answer:

   pm.test('Status code is 200', () => pm.response.to.have.status(200)); -> Option B

4. Quick Check:

   Correct syntax uses arrow function and .to.have.status() [OK]

Hint: Use arrow function and .to.have.status() for status checks [OK]

Common Mistakes:

• Passing boolean instead of function to pm.test()
• Using assignment '=' instead of comparison '=='
• Omitting parentheses in function declaration

3. Consider this test code in Postman:

pm.test('Response has userId 1', () => {
  const jsonData = pm.response.json();
  pm.expect(jsonData.userId).to.eql(1);
});

What will happen if the API response JSON is {"userId": 2}?

medium

A. The test will fail because userId is not 1

B. The test will pass because userId exists

C. The test will throw a syntax error

D. The test will be skipped automatically

Solution

1. Step 1: Understand the test assertion

   The test checks if jsonData.userId equals 1 using pm.expect().to.eql(1).

2. Step 2: Compare actual response value

   The response has userId as 2, which does not equal 1, so the assertion fails.

3. Final Answer:

   The test will fail because userId is not 1 -> Option A

4. Quick Check:

   Assertion fails if values differ = B [OK]

Hint: pm.expect() fails if actual ≠ expected [OK]

Common Mistakes:

• Assuming test passes if key exists
• Confusing eql() with assignment
• Thinking test skips on mismatch

4. You wrote this test in Postman:

pm.test('Check response time', () => {
  pm.expect(pm.response.responseTime).to.be.below(200);
});

But the test always fails even when response time is below 200ms. What is the likely error?

medium

A. The property pm.response.responseTime is correct, but the test function is missing parentheses

B. Incorrect property name; should be pm.response.response_time

C. The property pm.response.responseTime is correct, but the test fails if responseTime is undefined or not a number

D. Using to.be.below instead of to.be.lessThan

Solution

1. Step 1: Verify property name and assertion

   pm.response.responseTime is the correct property for response time in milliseconds, and to.be.below() is valid syntax.

2. Step 2: Consider why test fails despite correct syntax

   If responseTime is undefined or not a number, the assertion will fail even if the actual response time is low.

3. Final Answer:

   The property pm.response.responseTime is correct, but the test fails if responseTime is undefined or not a number -> Option C

4. Quick Check:

   Undefined or wrong type causes assertion failure = A [OK]

Hint: Check property exists and is number before asserting [OK]

Common Mistakes:

• Assuming wrong assertion method causes failure
• Using incorrect property names
• Missing parentheses in arrow function

5. You want to write a Postman test that checks if the response JSON contains a non-empty array called items and that each item has a price greater than 0. Which test code correctly implements this?

hard

A. pm.test('Items array and prices', () => {
const jsonData = pm.response.json();
pm.expect(Array.isArray(jsonData.items)).to.be.true;
pm.expect(jsonData.items.length).to.be.above(0);
jsonData.items.forEach(item => pm.expect(item.price).to.be.above(0));
});

B. pm.test('Items array and prices', () => {
const jsonData = pm.response.json();
pm.expect(jsonData.items).to.be.an('array').and.not.empty;
pm.expect(jsonData.items.every(item => item.price > 0)).to.be.true;
});

C. pm.test('Items array and prices', () => {
const jsonData = pm.response.json();
pm.expect(jsonData.items).to.exist;
pm.expect(jsonData.items.length > 0);
jsonData.items.forEach(item => pm.expect(item.price > 0));
});

D. pm.test('Items array and prices', () => {
const jsonData = pm.response.json();
pm.expect(jsonData.items).to.be.an('array');
pm.expect(jsonData.items.length).to.be.greaterThan(0);
jsonData.items.forEach(item => pm.expect(item.price).to.be.greaterThan(0));
});

Solution

1. Step 1: Check array existence and length

   pm.test('Items array and prices', () => { const jsonData = pm.response.json(); pm.expect(jsonData.items).to.be.an('array'); pm.expect(jsonData.items.length).to.be.greaterThan(0); jsonData.items.forEach(item => pm.expect(item.price).to.be.greaterThan(0)); }); correctly uses pm.expect(jsonData.items).to.be.an('array') and to.be.greaterThan(0) to verify the array is non-empty.

2. Step 2: Verify each item's price check

   pm.test('Items array and prices', () => { const jsonData = pm.response.json(); pm.expect(jsonData.items).to.be.an('array'); pm.expect(jsonData.items.length).to.be.greaterThan(0); jsonData.items.forEach(item => pm.expect(item.price).to.be.greaterThan(0)); }); uses pm.expect(item.price).to.be.greaterThan(0) inside a forEach loop, which is valid and clear.

3. Step 3: Compare with other options

   Options A and B use slightly different syntax but A uses to.be.above(0) which is valid but less common than to.be.greaterThan(0). B uses every() which is valid but chaining to.be.an('array').and.not.empty is not standard Chai syntax in Postman. C has incorrect assertions missing function calls.

4. Final Answer:

   Option D correctly implements all checks with valid syntax -> Option D

5. Quick Check:

   Use .to.be.an('array') and .to.be.greaterThan() for checks [OK]

Hint: Use .to.be.an('array') and .to.be.greaterThan() for clear checks [OK]

Common Mistakes:

• Using incorrect assertion chaining syntax
• Missing function calls in pm.expect()
• Not checking array length before iterating