@alu0100901214/espree-logging-module/src/logging-espree.js

Es un programa para parsear un fragmento de código.

const escodegen = require('escodegen');
const espree = require('espree');
const estraverse = require('estraverse');


const {version, description} = require('../package.json');
const fs = require('fs');

module.exports = { addLogging };

check = false;

/**
 * Add console.log in every Function.
 * @param {string} code String with the code.
 * @returns {string} Return the string with the console.log inserted.
 */
function addLogging(code, regexPattern) {
    var ast = espree.parse(code,{ecmaVersion: espree.latestEcmaVersion, loc: true});
    estraverse.traverse(ast, {
        enter: function(node, parent) {
            if (node.type === 'FunctionDeclaration' ||
                node.type === 'FunctionExpression'  ||
                node.type === 'ArrowFunctionExpression') {
                if (regexPattern != null){
                    if(node.id != null){
                        if(regexPattern.test(node.id.name))
                            addBeforeCode(node);
                    }
                }else{
                    addBeforeCode(node);
                }
            }
        }
    });
    return escodegen.generate(ast);
}

/**
 * Add logs to an AST node.
 * @param {object} node An AST node with the function, the console.log will be added inside.
 */
function addBeforeCode(node) {
    const name = node.id ? node.id.name : '<anonymous function>';
    const parameters = node.params.map(param => `\$\{${param.name}\}`);
    const beforeCode = `console.log(\`Entering ${name}(${parameters}) at line ${node.loc.start.line}\`);`;
    const beforeNodes = espree.parse(beforeCode, {ecmaVersion:6} ).body;
    node.body.body = beforeNodes.concat(node.body.body);
}