Error guessing in Testing Fundamentals - Framework Patterns

Framework Mode - Error guessing

Folder Structure for Error Guessing Test Approach

error-guessing-framework/
├── tests/
│   ├── error_guessing_tests.py
│   └── __init__.py
├── test_data/
│   └── common_error_inputs.json
├── utilities/
│   ├── error_patterns.py
│   └── __init__.py
├── config/
│   └── environment.yaml
├── reports/
│   └── latest_report.html
└── README.md
    

Test Framework Layers for Error Guessing

• Test Cases Layer: Contains test scripts that use error guessing to input likely error-causing data.
• Utilities Layer: Holds reusable functions and common error input patterns to help guess errors effectively.
• Test Data Layer: Stores data files with known error inputs or boundary values to try during testing.
• Configuration Layer: Manages environment settings like test URLs, credentials, and modes.
• Reporting Layer: Collects and formats test results for easy review.

Configuration Patterns

Use a YAML or JSON file to store environment details and test parameters.

# environment.yaml
base_url: "https://testapp.example.com"
browser: "chrome"
credentials:
  username: "testuser"
  password: "password123"
error_patterns_file: "test_data/common_error_inputs.json"
    

This lets you easily change environments or error input sets without changing test code.

Test Reporting and CI/CD Integration

• Generate HTML or XML reports summarizing which error guesses caused failures.
• Integrate with CI tools (like Jenkins or GitHub Actions) to run error guessing tests automatically on code changes.
• Use clear logs to show which error inputs were tested and their results.

Best Practices for Error Guessing Framework

1. Maintain a library of common error inputs: Keep updating your error patterns based on past bugs and domain knowledge.
2. Combine error guessing with other techniques: Use it alongside boundary value analysis and equivalence partitioning for better coverage.
3. Keep tests simple and focused: Each test should try a specific error input and check for graceful failure or proper error messages.
4. Automate error input generation: Use utilities to generate variations of error inputs to save time and reduce manual effort.
5. Log detailed results: Capture what input caused failure and why, to help developers fix issues quickly.

Self Check Question

Where in this folder structure would you add a new set of error input patterns for a recently discovered bug?

Key Result

Organize error guessing tests with clear layers for test cases, error input data, utilities, configuration, and reporting to efficiently find software errors.

Practice

1. What is the main idea behind Error guessing in software testing?

easy

A. Using formal test cases only

B. Writing automated tests for every function

C. Guessing where errors might occur based on experience

D. Ignoring past bugs and testing randomly

Solution

1. Step 1: Understand the concept of error guessing

   Error guessing is a technique where testers use their experience to predict where bugs might be.

2. Step 2: Compare options with the concept

   Only Guessing where errors might occur based on experience matches the idea of using experience to guess errors, others describe different testing methods.

3. Final Answer:

   Guessing where errors might occur based on experience -> Option C

4. Quick Check:

   Error guessing = Experience-based bug prediction [OK]

Hint: Error guessing is about experience, not formal rules [OK]

Common Mistakes:

• Confusing error guessing with automated testing
• Thinking error guessing ignores tester knowledge
• Believing error guessing is random testing

2. Which of the following is a correct example of an error guessing test case?

easy

A. Test all buttons for correct color

B. Test the software without any plan

C. Test only the homepage layout

D. Test input with empty fields to check validation

Solution

1. Step 1: Identify error guessing test case traits

   Error guessing focuses on inputs or actions likely to cause errors, like empty fields.

2. Step 2: Evaluate each option

   Test input with empty fields to check validation tests empty input, a common error source. Others are unrelated or random.

3. Final Answer:

   Test input with empty fields to check validation -> Option D

4. Quick Check:

   Empty input tests = Error guessing [OK]

Hint: Look for tests targeting likely error spots [OK]

Common Mistakes:

• Choosing tests unrelated to error conditions
• Confusing UI checks with error guessing
• Selecting random or unplanned tests

3. Given this scenario: A login form accepts username and password. Which input is best for error guessing?

medium

A. Username: 'admin', Password: '1234'

B. Username: '', Password: ''

C. Username: 'user1', Password: 'password'

D. Username: 'test', Password: 'test123'

Solution

1. Step 1: Identify inputs likely to cause errors

   Empty username and password fields often cause validation errors.

2. Step 2: Compare options for error likelihood

   Username: '', Password: '' uses empty inputs, which is a common error guess. Others are normal inputs.

3. Final Answer:

   Username: '', Password: '' -> Option B

4. Quick Check:

   Empty inputs = Common error guess [OK]

Hint: Empty or invalid inputs are classic error guesses [OK]

Common Mistakes:

• Choosing normal valid inputs
• Ignoring empty or boundary inputs
• Assuming random inputs are best

4. You wrote an error guessing test for a form but it never finds bugs. What is the most likely problem?

medium

A. You guessed errors in unlikely places

B. You wrote too many test cases

C. You automated all tests

D. You tested only the UI colors

Solution

1. Step 1: Understand error guessing effectiveness

   Error guessing works best when testers guess likely error spots based on experience.

2. Step 2: Analyze why tests fail to find bugs

   If guesses are in unlikely places, bugs won't be found. Other options don't explain this well.

3. Final Answer:

   You guessed errors in unlikely places -> Option A

4. Quick Check:

   Wrong guess spots = No bugs found [OK]

Hint: Guess where errors usually happen, not random places [OK]

Common Mistakes:

• Thinking more tests always find more bugs
• Believing automation replaces error guessing
• Focusing on UI style instead of error sources

5. You want to use error guessing to test a calculator app. Which combination of inputs is best to find errors?

hard

A. Very large numbers, zero, and dividing by zero

B. Random letters instead of numbers

C. Only positive integers

D. Normal numbers like 5 + 3, 10 - 2

Solution

1. Step 1: Identify error-prone inputs for calculator

   Calculators often fail with large numbers, zero, or division by zero.

2. Step 2: Evaluate options for error guessing effectiveness

   Very large numbers, zero, and dividing by zero targets these error-prone inputs, while others do not or are invalid inputs.

3. Final Answer:

   Very large numbers, zero, and dividing by zero -> Option A

4. Quick Check:

   Edge and invalid inputs = Best error guesses [OK]

Hint: Test edge cases and invalid inputs for errors [OK]

Common Mistakes:

• Testing only normal inputs
• Ignoring division by zero errors
• Using completely invalid inputs without context