Running tests (pytest command) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to run pytest from the command line.

PyTest

pytest [1]

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

A--help

B--version

C--run

D--test

Attempts:

3 left

💡 Hint

Common Mistakes

Using options that do not exist like --run or --test.

The --help option shows help information about pytest commands.

2fill in blank

medium

Complete the command to run tests in a specific file named test_sample.py.

PyTest

pytest [1]

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

Asample_test.py

Btest.py

Ctests.py

Dtest_sample.py

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect filenames that do not exist.

To run tests in a specific file, provide the exact filename to pytest.

3fill in blank

hard

Fix the error in the command to run pytest with verbose output.

PyTest

pytest [1]

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

A--verbose

B-verbose

C-v

D-verbose-output

Attempts:

3 left

💡 Hint

Common Mistakes

Using long or incorrect option names like --verbose or -verbose-output.

The correct short option for verbose mode in pytest is -v.

4fill in blank

hard

Fill both blanks to run pytest and stop after first failure with detailed output.

PyTest

pytest [1] [2]

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

A-v

B-q

C-x

D--maxfail=1

Attempts:

3 left

💡 Hint

Common Mistakes

Using --maxfail=1 instead of -x for stopping on failure.

-v enables verbose output and -x stops after the first failure.

5fill in blank

hard

Fill all three blanks to run pytest on a directory tests, show detailed output, and stop after 2 failures.

PyTest

pytest [1] [2] [3]

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

Atests

B-v

C--maxfail=2

D-x

Attempts:

3 left

💡 Hint

Common Mistakes

Using -x instead of --maxfail=2 to stop after two failures.

Run tests in tests directory, verbose output with -v, and stop after 2 failures using --maxfail=2.

Practice

1. What does the basic pytest command do when run in a project folder?

easy

A. It only checks the syntax of test files without running them.

B. It automatically finds and runs all test files and test functions.

C. It deletes all test files in the folder.

D. It installs pytest in the project folder.

Solution

1. Step 1: Understand the default behavior of pytest command

   Running pytest without arguments searches for test files and runs all tests found.

2. Step 2: Eliminate incorrect options

   Options A, C, and D describe actions pytest does not perform by default.

3. Final Answer:

   It automatically finds and runs all test files and test functions. -> Option B

4. Quick Check:

   pytest runs tests automatically = B [OK]

Hint: pytest runs all tests by default when no file is specified [OK]

Common Mistakes:

• Thinking pytest only checks syntax
• Assuming pytest deletes files
• Confusing pytest with package installer

2. Which of the following is the correct command to run pytest with detailed output?

easy

A. pytest -v

B. pytest --detail

C. pytest -d

D. pytest --verbose-output

Solution

1. Step 1: Recall pytest option for verbose output

   The -v option stands for verbose and shows detailed test results.

2. Step 2: Check other options for correctness

   Options -d, --detail, and --verbose-output are not valid pytest flags.

3. Final Answer:

   pytest -v -> Option A

4. Quick Check:

   Verbose flag is -v = C [OK]

Hint: Use -v for verbose pytest output [OK]

Common Mistakes:

• Using -d instead of -v
• Typing long incorrect flags
• Confusing verbose with debug flags

3. Given the command pytest test_math.py, what will happen?

medium

A. pytest runs all tests in all files in the folder.

B. pytest runs tests but ignores test_math.py.

C. pytest runs only the tests inside the file named test_math.py.

D. pytest runs tests only if they are named test_math.py inside any folder.

Solution

1. Step 1: Understand pytest file argument behavior

   When a filename is given, pytest runs tests only from that file.

2. Step 2: Eliminate incorrect options

   A: Runs all tests in all files (wrong when file specified). B: Ignores test_math.py (wrong). C: Misunderstands filename as test name search (wrong).

3. Final Answer:

   pytest runs only the tests inside the file named test_math.py. -> Option C

4. Quick Check:

   pytest filename runs tests in that file only = D [OK]

Hint: Specify filename to run tests only from that file [OK]

Common Mistakes:

• Assuming pytest runs all tests ignoring filename
• Confusing filename with test function name
• Thinking pytest ignores specified files

4. You run pytest -v test_example.py but get an error: pytest: error: unrecognized arguments: -v. What is the likely cause?

medium

A. pytest does not support the -v option.

B. You typed the option incorrectly; it should be --verbose.

C. The test file test_example.py does not exist.

D. You are running pytest with a wrong command or from a wrong environment.

Solution

1. Step 1: Understand the error message

   The error says -v is unrecognized, which is unusual because -v is a valid pytest option.

2. Step 2: Identify environment or command issues

   This usually means pytest is not properly installed or a different command is running (like python or another tool).

3. Final Answer:

   You are running pytest with a wrong command or from a wrong environment. -> Option D

4. Quick Check:

   Unrecognized option means wrong environment = A [OK]

Hint: Check pytest installation and environment if options fail [OK]

Common Mistakes:

• Assuming -v is invalid option
• Ignoring environment issues
• Blaming test file existence for option errors

5. You want to run only tests marked as slow in your project using pytest. Which command correctly runs only those tests?

hard

A. pytest -m slow

B. pytest --only slow

C. pytest --mark slow

D. pytest -s slow

Solution

1. Step 1: Recall pytest marker option

   The -m option runs tests matching a marker expression, such as slow.

2. Step 2: Verify other options

   Options --only, --mark, and -s do not filter tests by marker.

3. Final Answer:

   pytest -m slow -> Option A

4. Quick Check:

   Use -m to run tests by marker = A [OK]

Hint: Use -m marker to run tests with that marker [OK]

Common Mistakes:

• Using incorrect flags like --only or --mark
• Confusing -s (capture output) with marker filtering
• Not marking tests before filtering