Linter-On-Ruby

Linter is a static analysis tool such as RuboCop. It checks the written code and makes suggestions based on pre-defined rules by community-driven coding style guides and common idioms. Most definitions of linter default behavior can be changed for the needs of your team and project via various configuration options.

Requirement for the projects:

• A linter developed in Ruby
• It's a linter for beginners

Linter-On-Ruby is a beginner level linter that checks ruby .rb code files for the following rules:

• Maximum 100 lines per file
• Check the susceptible for def
• Maximum 80 characters per code line
• Check the susceptible for class
• Use of two spaces of indentation.
• Check the susceptible for end
• Exception in the line after a guard clause
• Check the susceptible for if
• No trailing spaces
• Check the susceptible for module
• Lack of EOF empty line

Example for Error-1

Example for Error-2

Folder Structure

Built With

• Ruby
• RSpec
• VSCode (Windows Application)

Getting started

To get a local copy of this repository up and running, follow these steps:

• Click the "Clone or download" button or run the follwing command

  git clone https://github.com/shubham14p3/Linter-On-Ruby.git

• Remeber to change the extentions of files present in lib/students codes to following :-

  • "some_ruby_file.rb.txt" to "some_ruby_file.rb"
  • "student_code1.rb.txt" to "student_code1.rb"
  • "student_code2.rb.txt" to "student_code2.rb"
  • "student_code3.rb.txt" to "student_code3.rb"
  • "student_code4.rb.txt" to "student_code4.rb"
  • "student_code5.rb.txt" to "student_code5.rb"
  • "student_code6.rb.txt" to "student_code6.rb"

• Type ruby bin/main.rb and press [Enter] and for

• Type main.rb file/path/you/want/to/check.rb on command line and press [Enter].

• To run Test cases just run RSPEC and press [Enter]

Samples

Indentation Cop

Detects indentation with the rules of two spaces indentation.

# Good

def my_method(arg1, arg2)
  variables = 12
end

# Bad

def my_method(arg1, arg2)
  variables = 12
  end

Max. 80 characters per line

# Bad

    if extra_large_condition1 && extra_large_condition2 && extra_large_condition3 && extra_large_condition4

# Good

    if extra_large_condition1 && extra_large_condition2 &&
      extra_large_condition3 && extra_large_condition4

Soft Paranthese Missing Cop

Calculates the total number of soft parantheses and returns the line number if closing and opening parantheses numbers doesn't match.

# Good

def my_method(arg1, arg2)
  variables = 12
end

# Bad

def my_method(arg1, arg2
  variables = 12
end

Use of two spaces of indentation

# Bad

        name = 'Carlos'
        if name.length > 4
            puts "Hello #{name}!" # tab or more than 2 spaces 
        end

# Good

        name = 'Carlos'
        if name.length > 4
          puts "Hello #{name}!"
        end

Square Bracket Missing Cop

Does the same for square brackets.

# Good

def my_method(arg1, arg2)
  variables = [12]
end

# Bad

def my_method(arg1, arg2)
  variables = [12
end

Exception in the line after a guard clause

# Good

        return unless File.exists?('file_name')
                          # empty line indentation can be 0 even if previous line is 4
        some other code

Curly Bracket Missing Cop

Does the same for curly brackets.

# Good

def my_method(arg1, arg2)
  variables = { symbol: "sample" }
end

# Bad

def my_method(arg1, arg2)
  variables = { symbol: "sample" 
end

Missing EOF empty line

# Bad

        name = 'Carlos'
        if name.length > 4
          puts "Hello #{name}!"
        end # file ends here

# Good

        name = 'Carlos'
        if name.length > 4
          puts "Hello #{name}!"
        end
        # file ends here

Extra Space Cop

It scans the lines and returns a note if it finds a bigger space than 1 character.

# Good

def my_method(arg1, arg2)
  variables = { symbol: "sample" }
end

# Bad

def my_method(arg1,     arg2)
  variables = { symbol: "sample" }
end

No trailing spaces

# Bad

        puts 'Hello, world!' # invisible trailing space here

# Good

        puts 'Hello, world!'  # the line ends with the last single quote

New Line Cop

If there is a keyword immediately before the 'end' keyword it returns an error message.

# Good

def my_method(arg1, arg2)
  variables = { symbol: "sample" }
end

def my_method2(arg1, arg2)
  variables = { symbol: "sample" }
end

# Bad

def my_method(arg1, arg2)
  variables = { symbol: "sample" }
end
def my_method2(arg1, arg2)
  variables = { symbol: "sample" }
end

Keyword 'end' Missing Cop

If the keywords numbers doesn't match with the end numbers it returns an error message with the line number of the latest end.

# Good

def my_method(arg1, arg2)
  variables = { symbol: "sample" }
end

# Bad

def my_method(arg1, arg2)
  variables = { symbol: "sample" }

Prerequisites

You must have Ruby installed on your computer

Linters Error Descriptions

Code in White Colors shows error for :-

• Maximum 100 lines per file
• Maximum 80 characters per code line
• Use of two spaces of indentation.
• Exception in the line after a guard clause
• No trailing spaces
• Lack of EOF empty line

Code in other Colors (Red, Yellow,etc) shows error for :-

• Check the susceptible for def
• Check the susceptible for module
• Check the susceptible for if
• Check the susceptible for end
• Check the susceptible for class

Authors

👤 Shubham Raj

• Github: @ShubhamRaj
• Linkedin: Shubham14p3

Future updates

• More specific conditions will be added. _ More linters feature needs to be added.

🤝 Contributing

Contributions, issues and feature requests are welcome!

Feel free to check the issues page.

Acknowledgments

• @Microverse
• My Family & Friends

📝 License

This project is MIT licensed.