capsys for capturing output in PyTest - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to capture printed output using capsys.

PyTest

def test_print(capsys):
    print("Hello, world!")
    captured = capsys.[1]()
    assert captured.out == "Hello, world!\n"

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

Areadouterr

Bcapture

Cgetoutput

Dcapture_output

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-existent method like 'capture' or 'getoutput'.

Trying to access output without calling the capture method.

The capsys.readouterr() method captures the output printed to stdout and stderr during the test.

2fill in blank

medium

Complete the code to assert the captured error output using capsys.

PyTest

def test_error_output(capsys):
    import sys
    print("Error happened", file=sys.stderr)
    captured = capsys.[1]()
    assert captured.err == "Error happened\n"

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

Acapture_error

Bcapture

Cgeterr

Dreadouterr

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to use a method that only captures stdout.

Using a non-existent method like 'geterr'.

The readouterr() method captures both stdout and stderr output, accessible via captured.out and captured.err.

3fill in blank

hard

Fix the error in the code to properly capture output with capsys.

PyTest

def test_fix(capsys):
    print("Test output")
    captured = capsys.[1]
    assert captured.out == "Test output\n"

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

Areadouterr()

Breadouterr

Ccapture()

Dcapture

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting parentheses after readouterr.

Using a non-existent method.

The readouterr() method must be called with parentheses to capture the output. Without parentheses, it is just a method reference.

4fill in blank

hard

Fill both blanks to capture output and assert it correctly.

PyTest

def test_multiple(capsys):
    print("Line 1")
    print("Line 2")
    captured = capsys.[1]()
    assert captured.[2] == "Line 1\nLine 2\n"

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

Areadouterr

Bout

Cerr

Dcapture

Attempts:

3 left

💡 Hint

Common Mistakes

Using captured.err when output is printed to stdout.

Not calling the capture method.

Use readouterr() to capture output, then access captured.out for standard output.

5fill in blank

hard

Fill all three blanks to capture output, split lines, and assert the first line.

PyTest

def test_split_lines(capsys):
    print("First line")
    print("Second line")
    captured = capsys.[1]()
    lines = captured.[2].split([3])
    assert lines[0] == "First line"

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

Areadouterr

Bout

C"\n"

Derr

Attempts:

3 left

💡 Hint

Common Mistakes

Using captured.err instead of captured.out.

Forgetting to call the capture method.

Splitting lines with wrong delimiter.

Use readouterr() to capture output, access captured.out, then split by newline "\n" to get lines.