Software Testing Strategies

Study Notes

Testing Strategies

Exhaustive Testing (Testing Hard): Attempts every possible input combination. For 32-bit integers, this involves 18 quintillion tests, impractical due to duplication.
Smart Testing (Testing Carefully): Selects test data strategically to avoid redundancy. Reduces the number of tests while maintaining confidence in software functionality.

Black Box Testing

Data Selection: Choose test values that aren't duplicates, and focus on cases where errors commonly occur. Testing 3 + 3 and 7 + 7 are essentially the same since they provide the same results.
Special Values: These are input values prone to causing errors which testing should specifically target:
- Zero: 0 inputs
- Negative values: Negative integer inputs
- Maximum and Minimum values: Extreme limits for variables
- Boundary values: Values immediately before and after the applicable range
- Error values: Invalid input, e.g., a non-numeric input
String Concatenation Example: Testing for diverse strings, including empty strings, long strings, and potential NULL arguments.
- General test cases: A combination of various types of strings (empty, short, long) with different characteristics
Focus on Error Cases: Testing for specific problematic scenarios.
- NULL parameters: Testing situations where input parameters can be NULL (pointer to nothing).
- Boundary cases of strings: Testing for strings with various lengths, including empty and long strings.

White Box Testing

Supplementing Black Box Tests: Identifies test cases not explicitly covered by black box testing, derived from code analysis.
- NULL handling for function parameters
Identifying Uncommon Situations: Focuses on code paths rarely executed.
- Exception handling: Error situations that might not be in the original requirements but have been addressed in the code as potential failure modes
Example: String Tokenizer: Checking for cases where the expected maximum number of words might be exceeded in string splitting.
- Maximum word limit: Testing situations where the max number of words are exceeded.
- Empty strings
- Strings containing a single word
Code Analysis Driven: White box testing examines the code to uncover scenarios not explicitly stated. This expands the test suite with new test cases crucial for comprehensive testing.

Description

Explore various software testing strategies such as exhaustive testing and smart testing that ensure software reliability. Understand the importance of black box testing and the significance of selecting special values to target potential errors in the software. This quiz covers critical concepts that every software tester should know.