ruby_colab.py

from IPython.core.magic import register_cell_magic
import subprocess
import os
import re
from sys import stderr
import shutil
import atexit

class RubySession:
    def __init__(self):
        """Initialize the Ruby session and ensure Ruby is installed."""
        self.code_history = []
        
        # Install Ruby if not present
        try:
            subprocess.run(['which', 'ruby'], check=True, capture_output=True)
            print("Ruby is already installed")
        except subprocess.CalledProcessError:
            print("Ruby is not installed, attempting to install...")
            if shutil.which('apt-get'):
                subprocess.run(['apt-get', 'update', '-y'], check=True)
                subprocess.run(['apt-get', 'install', '-y', 'ruby-full'], check=True)
                print("Ruby installation complete")
            else:
                print("Error: Cannot install Ruby automatically. Please install Ruby manually.")
                raise EnvironmentError("Ruby not found and automatic installation failed.")
                    
    def is_definition(self, code):
        """Check if the code contains definitions to be stored."""
        return bool(re.match(r'\s*(\w+\s*=|def\s|class\s)', code))
                    
    def execute(self, code):
        """Execute Ruby code within the session."""
        try:
            # Combine code history with new code using str.format()
            full_code = """
begin
  # Previous code
  {}

  # New code
  {}
rescue => e
  puts "Error: #{{e.class}} - #{{e.message}}"
  puts e.backtrace
end
""".format('\n  '.join(self.code_history), code)
            # Execute the code directly
            result = subprocess.run(['ruby'], 
                                    input=full_code, 
                                    capture_output=True, 
                                    text=True)
            # If execution was successful and code contains definitions, add to history
            if result.returncode == 0 and self.is_definition(code):
                self.code_history.append(code)
            return result.stdout, result.stderr
        except subprocess.CalledProcessError as e:
            return '', f"Subprocess error: {e}"
        except Exception as e:
            return '', f"Unexpected error: {e}"
            
    def cleanup(self):
        """Clean up temporary files."""
        pass  # No files to clean up since we're not writing to disk
        
    def reset(self):
        """Reset the session by clearing code history."""
        self.code_history = []

# Create global session
ruby_session = RubySession()

@register_cell_magic
def ruby(line, cell):
    if 'reset' in line:
        ruby_session.reset()
        print("Ruby session reset")
        return
    try:
        stdout, stderr_content = ruby_session.execute(cell)
        if stdout:
            print(stdout, end='')
        elif not stderr_content:
            print("Code executed successfully with no output.")
        if stderr_content:
            print(stderr_content, file=stderr, end='')
    except Exception as e:
        print(f"Error executing Ruby code: {e}", file=stderr)

# Register magic function and cleanup
get_ipython().register_magic_function(ruby, magic_kind='cell')
atexit.register(ruby_session.cleanup)

# User instructions
print("Ruby magic command ready! Use %%ruby to run Ruby code.")
print("Example:")
print("%%ruby")
print("puts 'Hello from Ruby!'")
print("\nTo reset the Ruby session, use:")
print("%%ruby reset")
print("Note: Be cautious when executing code that modifies the session state.")