Command-line options in PyTest - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to run pytest with verbose output.

PyTest

pytest [1]

Drag options to blanks, or click blank then click option'

A-v

B-q

C--maxfail=1

D--disable-warnings

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-q' which makes output quieter instead of verbose.

Using '--maxfail=1' which stops after one failure, not verbose output.

The -v option runs pytest in verbose mode, showing detailed test results.

2fill in blank

medium

Complete the command to stop pytest after the first failure.

PyTest

pytest [1]

Drag options to blanks, or click blank then click option'

A--maxfail=1

B-v

C-q

D--disable-warnings

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-v' which only changes verbosity.

Using '-q' which quiets output but does not stop on failure.

The --maxfail=1 option tells pytest to stop running tests after the first failure.

3fill in blank

hard

Fix the error in the command to disable warnings during pytest run.

PyTest

pytest [1]

Drag options to blanks, or click blank then click option'

A-dw

B-w

C--disable-warnings

D--no-warnings

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-w' which is not a valid pytest option.

Using '--no-warnings' which does not exist.

The correct option to disable warnings in pytest is --disable-warnings. Other options are invalid or do not exist.

4fill in blank

hard

Fill both blanks to run pytest quietly and stop after 2 failures.

PyTest

pytest [1] [2]

Drag options to blanks, or click blank then click option'

A-q

B-v

C--maxfail=2

D--disable-warnings

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-v' instead of '-q' for quiet mode.

Using '--maxfail=1' instead of 2.

The -q option runs pytest quietly, and --maxfail=2 stops after two failures.

5fill in blank

hard

Fill all three blanks to run pytest with verbose output, stop after 3 failures, and disable warnings.

PyTest

pytest [1] [2] [3]

Drag options to blanks, or click blank then click option'

A-v

B--maxfail=3

C--disable-warnings

D-q

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-q' instead of '-v' for verbosity.

Using wrong maxfail number.

Omitting the disable warnings option.

Use -v for verbose output, --maxfail=3 to stop after three failures, and --disable-warnings to hide warnings.

Practice

1. What does the pytest command-line option -v do when running tests?

easy

A. Runs tests only once without reruns

B. Runs tests in quiet mode, suppressing output

C. Generates a test coverage report

D. Runs tests in verbose mode, showing each test name

Solution

1. Step 1: Understand the -v option in pytest

   The -v option stands for verbose mode, which means pytest will show detailed information about each test it runs.

2. Step 2: Compare with other options

   Options like quiet mode or coverage report are different flags, so -v specifically increases output detail.

3. Final Answer:

   Runs tests in verbose mode, showing each test name -> Option D

4. Quick Check:

   Verbose = detailed output [OK]

Hint: Verbose means more details shown during test run [OK]

Common Mistakes:

• Confusing verbose with quiet mode
• Thinking it runs tests only once
• Mixing it with coverage report option

2. Which of the following is the correct syntax to run pytest and stop after the first failure?

easy

A. pytest -x

B. pytest --stop-on-failure

C. pytest --failfast=false

D. pytest -f

Solution

1. Step 1: Recall pytest option to stop on first failure

   The correct option is -x, which tells pytest to stop after the first test failure.

2. Step 2: Check other options for correctness

   --stop-on-failure and --failfast=false are invalid, and -f is not a recognized pytest option.

3. Final Answer:

   pytest -x -> Option A

4. Quick Check:

   Stop on first failure = -x [OK]

Hint: Use -x to stop pytest after first failure [OK]

Common Mistakes:

• Using long option names that don't exist
• Confusing -f with -x
• Assuming --failfast=false stops tests

3. Given the command pytest -k 'test_add or test_subtract' -v, what will pytest do?

medium

A. Run all tests except those named test_add or test_subtract

B. Run only tests named test_add or test_subtract with verbose output

C. Run tests with names containing 'test' only

D. Run tests and stop after first failure

Solution

1. Step 1: Understand the -k option

   The -k option filters tests by substring expressions. Here, it selects tests named test_add or test_subtract.

2. Step 2: Understand the -v option

   The -v option runs tests in verbose mode, showing detailed test names and results.

3. Final Answer:

   Run only tests named test_add or test_subtract with verbose output -> Option B

4. Quick Check:

   -k filters tests, -v shows details [OK]

Hint: -k filters tests by name, -v shows details [OK]

Common Mistakes:

• Thinking -k excludes tests instead of including
• Ignoring the verbose flag
• Assuming it stops on failure

4. You run pytest --maxfail=2 -v but pytest does not stop after 2 failures. What is the likely cause?

medium

A. You need to add -x to stop after max failures

B. The option --maxfail requires a space before the number

C. The --maxfail option is deprecated and ignored

D. You must use --maxfail=2 without -v

Solution

1. Step 1: Understand --maxfail behavior

   The --maxfail option sets how many failures to allow before stopping, but it requires -x to actually stop the test run.

2. Step 2: Check command usage

   Without -x, pytest will report max failures but continue running all tests.

3. Final Answer:

   You need to add -x to stop after max failures -> Option A

4. Quick Check:

   --maxfail needs -x to stop tests [OK]

Hint: Add -x with --maxfail to stop tests early [OK]

Common Mistakes:

• Thinking --maxfail alone stops tests
• Adding space between --maxfail and number
• Assuming -v disables maxfail

5. You want to run pytest only on tests marked as slow and generate a JUnit XML report saved as results.xml. Which command is correct?

hard

A. pytest --only-mark slow --junitxml results.xml

B. pytest --mark slow --xml=results.xml

C. pytest -m slow --junitxml=results.xml

D. pytest -m slow -x --junit=results.xml

Solution

1. Step 1: Use -m to select tests by marker

   The -m option filters tests by marker name, so -m slow runs only tests marked as slow.

2. Step 2: Use --junitxml=filename to generate report

   The --junitxml=results.xml option saves test results in JUnit XML format to the specified file.

3. Step 3: Verify other options are invalid

   Options like --mark, --xml, and --only-mark are not valid pytest flags.

4. Final Answer:

   pytest -m slow --junitxml=results.xml -> Option C

5. Quick Check:

   -m for marker, --junitxml for report [OK]

Hint: Use -m for markers and --junitxml for reports [OK]

Common Mistakes:

• Using incorrect flags like --mark or --xml
• Forgetting = between --junitxml and filename
• Adding -x which stops tests unnecessarily