When is it appropriate to use C++ function unit testing?

Functional unit testing is an automated testing technique used to test the expected behavior of a C function in isolation. Applicable to the following scenarios: Verify function behavior Check boundary conditions Detect errors Refactor code as documentation

When to use C function unit testing

Function unit testing is an automated testing technology that performs isolated testing of C functions. It helps you ensure that functions work as expected and detect edge cases or errors.

Here are some situations when it is appropriate to use function unit testing:

• Verify the behavior of the function: Test whether the function returns the expected value according to the specification.
• Check boundary conditions: Test the behavior of a function outside the input or output range.
• Detecting errors: Identify problems that cause functions to behave unexpectedly.
• When refactoring code: Make sure that code changes do not accidentally affect the behavior of the function.
• As documentation: Unit tests can serve as detailed descriptions of the expected behavior of a function.

Practical Case

Let us consider a simple C function that calculates the sum of two numbers:

int add(int a, int b) {
  return a + b;
}

We can use Google Test framework writes a unit test to verify the behavior of this function:

#include 

TEST(AddFunctionTest, PositiveNumbers) {
  EXPECT_EQ(add(1, 2), 3);
  EXPECT_EQ(add(4, 5), 9);
}

TEST(AddFunctionTest, NegativeNumbers) {
  EXPECT_EQ(add(-1, -2), -3);
  EXPECT_EQ(add(-3, -4), -7);
}

Code description:

• TEST() Macro definition A unit test.
• EXPECT_EQ() Asserts that two expressions have equal values.
• We can write multiple test cases for each different test case.

Running these tests will verify the expected behavior of the add() function under different inputs.

The above is the detailed content of When is it appropriate to use C++ function unit testing?. For more information, please follow other related articles on the PHP Chinese website!