add learning paths

Author: ythirion

README.md

@@ -46,30 +46,30 @@ To facilitate the communication around challenges you can join us on `Discord` b
 ## Challenges - 2023
 Here are the different challenges :
 
-- [Day 1: Make your production code easier to understand.](exercise/day01/docs/challenge.md)
-- [Day 2: One level of indentation.](exercise/day02/docs/challenge.md)
-- [Day 3: One dot per line.](exercise/day03/docs/challenge.md)
-- [Day 4: Identify the behavior under test and rewrite the tests.](exercise/day04/docs/challenge.md)
-- [Day 5: No "for" loop authorized.](exercise/day05/docs/challenge.md)
-- [Day 6: Parameterize your tests.](exercise/day06/docs/challenge.md)
-- [Day 7: Simplify the run method by extracting the right behavior.](exercise/day07/docs/challenge.md)
-- [Day 8: Using TDD rules, write a password validation program.](exercise/day08/docs/challenge.md)
-- [Day 9: Fix the code.](exercise/day09/docs/challenge.md)
-- [Day 10: Dot not use "if" statement.](exercise/day10/docs/challenge.md)
-- [Day 11: Gather a dependency freshness metric.](exercise/day11/docs/challenge.md)
-- [Day 12: Make your code open for extension.](exercise/day12/docs/challenge.md)
-- [Day 13: Find a way to eliminate the irrelevant, and amplify the essentials of those tests.](exercise/day13/docs/challenge.md)
-- [Day 14: Do not use exceptions anymore.](exercise/day14/docs/challenge.md)
-- [Day 15: Put a code under tests.](exercise/day15/docs/challenge.md)
-- [Day 16: Make this code immutable.](exercise/day16/docs/challenge.md)
-- [Day 17: Design one test that has the impact of thousands.](exercise/day17/docs/challenge.md)
-- [Day 18: Automatically detect Linguistic Anti-Patterns (LAP).](exercise/day18/docs/challenge.md)
-- [Day 19: Loosing up dead weight.](exercise/day19/docs/challenge.md)
-- [Day 20: No more exceptions in our domain.](exercise/day20/docs/challenge.md)
-- [Day 21: Refactor the tests and production code to Output-Based tests.](exercise/day21/docs/challenge.md)
-- [Day 22: Design a diamond program using T.D.D and Property-Based Testing.](exercise/day22/docs/challenge.md)
-- [Day 23: Refactor the code after putting it under test.](exercise/day23/docs/challenge.md)
-- [Day 24: Write the most complicated code you can.](exercise/day24/docs/challenge.md)
+- [Day 1: Make your production code easier to understand.](exercise/day01/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md)
+- [Day 2: One level of indentation.](exercise/day02/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md)
+- [Day 3: One dot per line.](exercise/day03/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md)
+- [Day 4: Identify the behavior under test and rewrite the tests.](exercise/day04/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 5: No "for" loop authorized.](exercise/day05/docs/challenge.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md)
+- [Day 6: Parameterize your tests.](exercise/day06/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 7: Simplify the run method by extracting the right behavior.](exercise/day07/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md)
+- [Day 8: Using TDD rules, write a password validation program.](exercise/day08/docs/challenge.md) [![T.D.D](https://img.shields.io/badge/T.D.D-green)](learning-paths/tdd.md)
+- [Day 9: Fix the code.](exercise/day09/docs/challenge.md) [![Design](https://img.shields.io/badge/Design-yellow)](learning-paths/design.md)
+- [Day 10: Dot not use "if" statement.](exercise/day10/docs/challenge.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md)
+- [Day 11: Gather a dependency freshness metric.](exercise/day11/docs/challenge.md) [![Design](https://img.shields.io/badge/Design-yellow)](learning-paths/design.md)
+- [Day 12: Make your code open for extension.](exercise/day12/docs/challenge.md) [![Design](https://img.shields.io/badge/Design-yellow)](learning-paths/design.md)
+- [Day 13: Find a way to eliminate the irrelevant, and amplify the essentials of those tests.](exercise/day13/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 14: Do not use exceptions anymore.](exercise/day14/docs/challenge.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md)
+- [Day 15: Put a code under tests.](exercise/day15/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 16: Make this code immutable.](exercise/day16/docs/challenge.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md)
+- [Day 17: Design one test that has the impact of thousands.](exercise/day17/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 18: Automatically detect Linguistic Anti-Patterns (LAP).](exercise/day18/docs/challenge.md) [![Design](https://img.shields.io/badge/Design-yellow)](learning-paths/design.md)
+- [Day 19: Loosing up dead weight.](exercise/day19/docs/challenge.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md)
+- [Day 20: No more exceptions in our domain.](exercise/day20/docs/challenge.md) [![Design](https://img.shields.io/badge/Design-yellow)](learning-paths/design.md)
+- [Day 21: Refactor the tests and production code to Output-Based tests.](exercise/day21/docs/challenge.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md)
+- [Day 22: Design a diamond program using T.D.D and Property-Based Testing.](exercise/day22/docs/challenge.md) [![T.D.D](https://img.shields.io/badge/T.D.D-green)](learning-paths/tdd.md)
+- [Day 23: Refactor the code after putting it under test.](exercise/day23/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md) [![T.D.D](https://img.shields.io/badge/T.D.D-green)](learning-paths/tdd.md) [![Clean Testing](https://img.shields.io/badge/Clean%20Testing-orange)](learning-paths/clean-testing.md) [![Functional Programming](https://img.shields.io/badge/Functional%20Programming-purple)](learning-paths/functional-programming.md) 
+- [Day 24: Write the most complicated code you can.](exercise/day24/docs/challenge.md) [![Refactoring](https://img.shields.io/badge/Refactoring-blue)](learning-paths/refactoring.md)
 - [Day 25: Share with the world what you have learned.](exercise/day25/docs/challenge.md)
 
 ### Solutions
@@ -99,7 +99,15 @@ A solution proposal will be published here every day during the `Advent Of Craft
 - [Day 22: Design a diamond program using T.D.D and Property-Based Testing.](solution/day22/docs/step-by-step.md)
 - [Day 23: Refactor the code after putting it under test.](solution/day23/docs/step-by-step.md)
 - [Day 24: Write the most complicated code you can.](solution/day24/docs/step-by-step.md)
- 
+
+## Learning paths 🚀
+We have designed several `learning paths` based on the challenges that you can follow if you want to deep dive into a given concept:
+- [Refactoring 🚀](learning-paths/refactoring.md)
+- [Clean Testing 🧼](learning-paths/clean-testing.md)
+- [Test-Driven Development 🔴🔵🟢](learning-paths/tdd.md)
+- [Design 🏛](learning-paths/design.md)
+- [Functional Programming 🌋](learning-paths/functional-programming.md)
+
 ## Contributors
 
 <table>

img/clean-testing.png

@@ -0,0 +1,29 @@
+## Clean Testing 🧼
+![Clean Testing Learning path](../img/clean-testing.png)
+
+- [Day 4: Identify the behavior under test and rewrite the tests.](../exercise/day04/docs/challenge.md)
+  - Focus tests on behaviors (not data)
+  - Tests List
+  - Avoid duplication (Clean Code applied on tests)
+- [Day 6: Parameterize your tests.](../exercise/day06/docs/challenge.md)
+  - Parameterized tests
+- [Day 13: Find a way to eliminate the irrelevant, and amplify the essentials of those tests.](../exercise/day13/docs/challenge.md)
+  - Test Data Builder
+  - `DSL` for our tests
+- [Day 15: Put a code under tests.](../exercise/day15/docs/challenge.md)
+  - Approval testing
+  - Combination testing
+  - Work effectively with legacy code
+- [Day 17: Design one test that has the impact of thousands.](../exercise/day17/docs/challenge.md)
+  - Property-Based Testing
+  - From `Parameterized tests` to `Property-Based tests`
+- [Day 21: Refactor the tests and production code to Output-Based tests.](../exercise/day21/docs/challenge.md)
+  - Styles of Tests
+    - State-Based
+    - Output-Based
+    - Communication-Based
+  - Refactor to Output-Based tests
+  - Functional Core, Imperative Shell
+- [Day 23: Refactor the code after putting it under test.](../exercise/day23/docs/challenge.md)
+  - Code coverage
+  - Mutation Testing

img/design.png

@@ -0,0 +1,22 @@
+## Design 🏛️
+![Design Learning path](../img/design.png)
+
+- [Day 9: Fix the code.](../exercise/day09/docs/challenge.md)
+  - Command Query Separation
+  - Pure Function
+- [Day 11: Gather a dependency freshness metric.](../exercise/day11/docs/challenge.md)
+  - Dependency Freshness
+  - LibYear
+  - Team Rules
+- [Day 12: Make your code open for extension.](../exercise/day12/docs/challenge.md)
+  - S.O.L.I.D Principles
+  - C.U.P.I.D
+  - Open-Closed Principle
+- [Day 18: Automatically detect Linguistic Anti-Patterns (LAP).](../exercise/day18/docs/challenge.md)
+  - Linguistic Anti-Patterns
+  - Architecture Unit Tests
+  - Team Rules
+- [Day 20: No more exceptions in our domain.](../exercise/day20/docs/challenge.md)
+  - Hollywood principle / continuation
+  - Constrain inputs
+  - Referential transparency

img/functional-programming.png

@@ -0,0 +1,24 @@
+## Functional Programming 🌋
+![FP Learning path](../img/functional-programming.png)
+
+- [Day 5: No "for" loop authorized.](../exercise/day05/docs/challenge.md)
+  - Use Collection Functions
+- [Day 10: Dot not use "if" statement.](../exercise/day10/docs/challenge.md)
+  - Pure Function
+  - Functional Map (function registration)
+  - Object Calisthenics
+- [Day 14: Do not use exceptions anymore.](../exercise/day14/docs/challenge.md)
+  - Parse Don't Validate
+  - Use Monads instead of Exceptions
+  - Extend Output
+  - Referential Transparency
+- [Day 16: Make this code immutable.](../exercise/day16/docs/challenge.md)
+  - Immutability
+  - Use `T.D.D` to refactor existing code
+  - Strangler Pattern
+- [Day 19: Loosing up dead weight.](../exercise/day19/docs/challenge.md)
+  - Exceptions vs Errors
+  - Use error instead of exceptions
+- [Day 23: Refactor the code after putting it under test.](../exercise/day23/docs/challenge.md)
+  - Use Monads
+  - Referential Transparency

img/refactoring.png

@@ -0,0 +1,26 @@
+## Refactoring 🚀
+![Refactoring Learning path](../img/refactoring.png)
+
+- [Day 1: Make your production code easier to understand.](../exercise/day01/docs/challenge.md)
+    - Encapsulate Conditionals
+    - Extract Method
+    - Automated Refactoring
+- [Day 2: One level of indentation.](../exercise/day02/docs/challenge.md)
+  - Object Calisthenics
+  - Invert If
+  - Extract Method
+  - Guard
+  - Automated Refactoring
+- [Day 3: One dot per line.](../exercise/day03/docs/challenge.md)
+  - Object Calisthenics
+  - Extract Method
+  - Law of Demeter
+- [Day 7: Simplify the run method by extracting the right behavior.](../exercise/day07/docs/challenge.md)
+  - Reduce cognitive load by extracting methods
+  - More about cognitive load [here](https://speakerdeck.com/thirion/clean-code-du-point-de-vue-de-la-cognition)
+- [Day 23: Refactor the code after putting it under test.](../exercise/day23/docs/challenge.md)
+  - Refactor Legacy Code
+  - Seams
+  - [Day 24: Write the most complicated code you can.](../exercise/day24/docs/challenge.md)
+  - Crappy-Driven Development
+  - Clean Code

img/tdd.png

@@ -0,0 +1,20 @@
+## Test-Driven Development 🔴🔵🟢
+![TDD Learning path](../img/tdd.png)
+
+- [Day 8: Using TDD rules, write a password validation program.](../exercise/day08/docs/challenge.md)
+  - Example Mapping
+  - Tests list
+  - Triangulation
+  - Baby steps
+  - Parameterized Tests
+  - Regex
+  - `ChatGPT` 🤪
+- [Day 22: Design a diamond program using T.D.D and Property-Based Testing.](../exercise/day22/docs/challenge.md)
+  - Property-Based Testing
+  - Triangulate with PBT
+  - Monads
+  - Parse Don't Validate
+  - Approval Testing
+  - **T**est && **C**ommit || **R**evert (`TCR`)
+- [Day 23: Refactor the code after putting it under test.](../exercise/day23/docs/challenge.md)
+  - Sprout Technique