Comparing values (equality, inequality) in PyTest - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the variable result equals 10 using pytest.

PyTest

def test_result():
    result = 10
    assert result [1] 10

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

A==

B<

C>

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '!=' instead of '==' causes the test to fail.

Using '>' or '<' checks for greater or less, not equality.

The == operator checks if two values are equal. Here, assert result == 10 verifies that result is exactly 10.

2fill in blank

medium

Complete the code to assert that value is not equal to 5.

PyTest

def test_value_not_five():
    value = 3
    assert value [1] 5

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

A<=

B!=

C>=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' will fail if value is not 5.

Using '>=' or '<=' checks range, not inequality.

The != operator checks that two values are not equal. Here, assert value != 5 confirms value is anything but 5.

3fill in blank

hard

Fix the error in the assertion to check if score is greater than or equal to 50.

PyTest

def test_score():
    score = 75
    assert score [1] 50

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

A==

B<

C!=

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' only checks equality, not greater values.

Using '<' checks if less, which is the opposite of what we want.

The >= operator checks if the left value is greater than or equal to the right value. Here, assert score >= 50 ensures score is at least 50.

4fill in blank

hard

Fill both blanks to assert that temperature is less than 100 and not equal to 0.

PyTest

def test_temperature():
    temperature = 75
    assert temperature [1] 100 and temperature [2] 0

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

A<

B!=

C>

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '<' for the first blank reverses the logic.

Using '==' instead of '!=' for the second blank causes wrong assertion.

The first blank uses < to check if temperature is less than 100. The second blank uses != to ensure it is not zero.

5fill in blank

hard

Fill all three blanks to create a test that asserts age is greater than 18, less than 65, and not equal to 30.

PyTest

def test_age():
    age = 40
    assert age [1] 18 and age [2] 65 and age [3] 30

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

A>

B<

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up '<' and '>' operators.

Using '==' instead of '!=' for the last condition.

The test checks three things: age > 18, age < 65, and age != 30. This ensures age is between 19 and 64 but not 30.

Practice

1. Which operator in pytest assertions checks if two values are equal?

easy

A. <

B. !=

C. >

D. ==

Solution

1. Step 1: Understand equality operator

   The operator == is used to check if two values are equal in Python and pytest assertions.

2. Step 2: Differentiate from inequality

   The operator != checks if values are not equal, so it is not the correct choice for equality.

3. Final Answer:

   == -> Option D

4. Quick Check:

   Equality check = == [OK]

Hint: Use == for equality, != for inequality [OK]

Common Mistakes:

• Confusing == with !=
• Using > or < for equality
• Forgetting to use assertion keyword

2. Which of the following is the correct syntax to assert that variable a is not equal to b in pytest?

easy

A. assert a != b

B. assert a =! b

C. assert a ==! b

D. assert a = b

Solution

1. Step 1: Identify correct inequality syntax

   The correct operator for inequality is !=, so the assertion should be assert a != b.

2. Step 2: Check syntax correctness

   Options with =! or ==! are invalid syntax and will cause errors.

3. Final Answer:

   assert a != b -> Option A

4. Quick Check:

   Inequality assertion = assert a != b [OK]

Hint: Remember: inequality is !=, not =! or ==! [OK]

Common Mistakes:

• Using =! instead of !=
• Using = instead of ==
• Mixing equality and inequality operators

3. What will be the result of this pytest assertion?

def test_numbers():
    x = 10
    y = 5 + 5
    assert x == y

medium

A. Syntax error in assertion

B. Test fails because 10 does not equal 5

C. Test passes because 10 equals 10

D. Test fails because variables are different

Solution

1. Step 1: Calculate values of variables

   Variable x is 10, and y is calculated as 5 + 5, which equals 10.

2. Step 2: Evaluate assertion condition

   The assertion assert x == y checks if 10 equals 10, which is true, so the test passes.

3. Final Answer:

   Test passes because 10 equals 10 -> Option C

4. Quick Check:

   10 == 10 is True [OK]

Hint: Add values before comparing for equality [OK]

Common Mistakes:

• Assuming variables differ without calculation
• Confusing syntax errors with logic errors
• Ignoring that 5 + 5 equals 10

4. Identify the error in this pytest assertion:

def test_strings():
    s1 = "hello"
    s2 = "Hello"
    assert s1 != s2

medium

A. No error, test passes because strings differ in case

B. Syntax error due to missing parentheses

C. Assertion should use == instead of !=

D. Variables s1 and s2 are not defined

Solution

1. Step 1: Compare string values with case sensitivity

   Strings "hello" and "Hello" differ in case, so they are not equal.

2. Step 2: Check assertion correctness

   The assertion assert s1 != s2 correctly checks that the strings are not equal, so the test passes without error.

3. Final Answer:

   No error, test passes because strings differ in case -> Option A

4. Quick Check:

   "hello" != "Hello" is True [OK]

Hint: String comparison is case-sensitive by default [OK]

Common Mistakes:

• Assuming strings are equal ignoring case
• Expecting syntax error without parentheses in assert
• Confusing == and != in assertions

5. You want to write a pytest test to check that a function get_status() returns a value that is not equal to None. Which assertion is the best choice?

hard

A. assert get_status() == None

B. assert get_status() is not None

C. assert get_status() != None

D. assert get_status() is None

Solution

1. Step 1: Understand None comparison best practice

   In Python, to check if a value is not None, the recommended way is to use is not None rather than != None.

2. Step 2: Evaluate options for correctness

   assert get_status() == None checks equality to None (wrong for this case). assert get_status() != None uses != None (works but not best practice). assert get_status() is not None uses is not None which is best practice. assert get_status() is None checks if value is None (opposite of requirement).

3. Final Answer:

   assert get_status() is not None -> Option B

4. Quick Check:

   Use 'is not None' for None checks [OK]

Hint: Use 'is not None' to check for non-None values [OK]

Common Mistakes:

• Using == None instead of is None
• Using != None instead of is not None
• Confusing equality with identity for None