update

Author: meleu

README.md

@@ -4,6 +4,8 @@
 
 This "book" is my attempt to teach idiomatic **Ruby** and **Test-Driven Development** (TDD).
 
+(spoiler: we're going to use **Minitest**, not RSpec)
+
 ## Why?
 
 ### Why Ruby?
@@ -32,7 +34,9 @@ The chapters are presented in a sequence where new Ruby features are introduced
 
 Initially the cycle may seem tedious, but as you progress through the book you'll see how productive it is to get instant feedback on your work.
 
-You'll notice that the programs we'll code are really simple. That's intentional. The greatest value will be in the way we solve the problems. The tools we use, the tests we write, the way we organize our code...
+In the first chapters we use a [procedural programming paradigm](https://en.wikipedia.org/wiki/Procedural_programming) to show both the fundamentals of Ruby syntax and how TDD works. Once the basic Ruby concepts are addressed we start to write our code using Object-Oriented Programming.
+
+You'll notice that the programs are really simple. That's intentional. The greatest value will be in the way we solve the problems. The tools we use, the tests we write, the way we organize our code...
 
 If I used "real world problems", I would need to spend words explaining the problem's domain and then talk about the techniques. That would be lengthy and confusing. By keeping the problems simple, I'm sure you'll find a way to adapt the techniques to the "real world problem" you have to solve.
 

bibliography.md

@@ -3,8 +3,9 @@ This is an **incomplete** list of books and links I consulted and/or was inspire
 - [Learn Go with Tests](https://quii.gitbook.io/learn-go-with-tests), Chris James
 - [The Well-Grounded Rubyist](https://www.manning.com/books/the-well-grounded-rubyist-third-edition), 3rd edition
 - [Practical Object-Oriented Design in Ruby](https://www.poodr.com), Sandi Metz
+- [Test-Driven Development By Example](https://www.oreilly.com/library/view/test-driven-development/0321146530/), Kent Beck
 - [Tidy First?](https://www.oreilly.com/library/view/tidy-first/9781098151232/), Kent Beck
 - [Learning Test-Driven Development](https://learning.oreilly.com/library/view/learning-test-driven-development/9781098106461/), Saleem Siddiqui
-- [Ruby in 100 Minutes](http://tutorials.jumpstartlab.com/projects/ruby_in_100_minutes.html), JumpstartLab
+- [Ruby in 100 Minutes](https://web.archive.org/web/20240115073552/http://tutorials.jumpstartlab.com/projects/ruby_in_100_minutes.html), JumpstartLab
 
 I'll be adding more references as I use them.

hello-world.md

@@ -627,7 +627,7 @@ We learn a bunch of things here.
 - `case` statements
 - how to write tests with Minitest
 
-### TDD
+### Testing
 
 The TDD process and _why_ the steps are important
 

loops-blocks-and-strings.md

@@ -544,7 +544,7 @@ git commit -m 'fix(banner): handle multiline text'
   - `each_line`
   - `chomp`
 
-### TDD
+### Testing
 
 - Reinforced TDD practices (write test first!)
 - After receiving a bug report:

objects-methods-and-integers.md

@@ -43,7 +43,23 @@ Now let's start our _Decimal to Binary Converter™_ project following the TDD c
 
 ### Write the test first
 
-We still have no idea about how to implement this converter, but by looking at the [Wikipedia page about binary numbers](https://simple.wikipedia.org/wiki/Binary_number) we can see a table with some equivalents. Here are some examples:
+We still have no idea about how to implement this converter, then *how can we write a test for a code that doesn't even exist?!* That's strong and valid question. The answer is: **write the test using the best interface you can think of to perform the operation**.
+
+Keeping this in mind, I list here my ideas for a great interface to a function able to convert a decimal number to its binary representation:
+
+- a function named `dec2bin`
+- it accepts an integer number as the only argument
+- it returns the binary representation of the given number
+
+Something like this:
+
+```ruby
+binary = dec2bin(123)
+```
+
+Yeah, that looks good. Let's go ahead and create a test for that (inexistent) function!
+
+We will need to, at least, know what would be a successful conversion. For this I use the [Wikipedia page about binary numbers](https://simple.wikipedia.org/wiki/Binary_number), where we can see a table like this:
 
 | decimal | binary |
 | :-----: | -----: |
@@ -74,7 +90,7 @@ class TestDec2Bin < Minitest::Test
 end
 ```
 
-Let's run this test and see the error message.
+Run this test and check the error message.
 
 ### Error vs. Failure
 
@@ -512,7 +528,7 @@ Let's recap what we learned in this chapter.
 - `gets`: read user's input
 - method chaining: calling multiple methods in sequence (e.g.: `number.to_i.to_s(2)`)
 
-### TDD
+### Testing
 
 - Test-first approach: write the test before implementation code.
 - Test Error vs. Test Failure

ruby-tooling.md

@@ -18,7 +18,7 @@ The Ruby community has two main testing frameworks:
 In this book we're going to use **Minitest**, for two reasons:
 
 1. it comes with the Ruby Standard Library.
-2. "it doesn’t reinvent anything that ruby already provides. This means you only have to learn ruby to use minitest" - (from [minitest's README](https://github.com/minitest/minitest?tab=readme-ov-file#description-))
+2. you only have to know ruby to use Minitest
 
 ## Ruby documentation