babel-plugin-macros/dist/index.js

"use strict";

const p = require('path');

const resolve = require('resolve'); // const printAST = require('ast-pretty-print')


const macrosRegex = /[./]macro(\.c?js)?$/;

const testMacrosRegex = v => macrosRegex.test(v); // https://stackoverflow.com/a/32749533/971592


class MacroError extends Error {
  constructor(message) {
    super(message);
    this.name = 'MacroError';
    /* istanbul ignore else */

    if (typeof Error.captureStackTrace === 'function') {
      Error.captureStackTrace(this, this.constructor);
    } else if (!this.stack) {
      this.stack = new Error(message).stack;
    }
  }

}

let _configExplorer = null;

function getConfigExplorer() {
  return _configExplorer = _configExplorer || // Lazy load cosmiconfig since it is a relatively large bundle
  require('cosmiconfig').cosmiconfigSync('babel-plugin-macros', {
    searchPlaces: ['package.json', '.babel-plugin-macrosrc', '.babel-plugin-macrosrc.json', '.babel-plugin-macrosrc.yaml', '.babel-plugin-macrosrc.yml', '.babel-plugin-macrosrc.js', 'babel-plugin-macros.config.js'],
    packageProp: 'babelMacros'
  });
}

function createMacro(macro, options = {}) {
  if (options.configName === 'options') {
    throw new Error(`You cannot use the configName "options". It is reserved for babel-plugin-macros.`);
  }

  macroWrapper.isBabelMacro = true;
  macroWrapper.options = options;
  return macroWrapper;

  function macroWrapper(args) {
    const {
      source,
      isBabelMacrosCall
    } = args;

    if (!isBabelMacrosCall) {
      throw new MacroError(`The macro you imported from "${source}" is being executed outside the context of compilation with babel-plugin-macros. ` + `This indicates that you don't have the babel plugin "babel-plugin-macros" configured correctly. ` + `Please see the documentation for how to configure babel-plugin-macros properly: ` + 'https://github.com/kentcdodds/babel-plugin-macros/blob/master/other/docs/user.md');
    }

    return macro(args);
  }
}

function nodeResolvePath(source, basedir) {
  return resolve.sync(source, {
    basedir,
    // This is here to support the package being globally installed
    // read more: https://github.com/kentcdodds/babel-plugin-macros/pull/138
    paths: [p.resolve(__dirname, '../../')]
  });
}

function macrosPlugin(babel, // istanbul doesn't like the default of an object for the plugin options
// but I think older versions of babel didn't always pass options
// istanbul ignore next
{
  require: _require = require,
  resolvePath = nodeResolvePath,
  isMacrosName = testMacrosRegex,
  ...options
} = {}) {
  function interopRequire(path) {
    // eslint-disable-next-line import/no-dynamic-require
    const o = _require(path);

    return o && o.__esModule && o.default ? o.default : o;
  }

  return {
    name: 'macros',
    visitor: {
      Program(progPath, state) {
        progPath.traverse({
          ImportDeclaration(path) {
            const isMacros = looksLike(path, {
              node: {
                source: {
                  value: v => isMacrosName(v)
                }
              }
            });

            if (!isMacros) {
              return;
            }

            const imports = path.node.specifiers.map(s => ({
              localName: s.local.name,
              importedName: s.type === 'ImportDefaultSpecifier' ? 'default' : s.imported.name
            }));
            const source = path.node.source.value;
            const result = applyMacros({
              path,
              imports,
              source,
              state,
              babel,
              interopRequire,
              resolvePath,
              options
            });

            if (!result || !result.keepImports) {
              path.remove();
            }
          },

          VariableDeclaration(path) {
            const isMacros = child => looksLike(child, {
              node: {
                init: {
                  callee: {
                    type: 'Identifier',
                    name: 'require'
                  },
                  arguments: args => args.length === 1 && isMacrosName(args[0].value)
                }
              }
            });

            path.get('declarations').filter(isMacros).forEach(child => {
              const imports = child.node.id.name ? [{
                localName: child.node.id.name,
                importedName: 'default'
              }] : child.node.id.properties.map(property => ({
                localName: property.value.name,
                importedName: property.key.name
              }));
              const call = child.get('init');
              const source = call.node.arguments[0].value;
              const result = applyMacros({
                path: call,
                imports,
                source,
                state,
                babel,
                interopRequire,
                resolvePath,
                options
              });

              if (!result || !result.keepImports) {
                child.remove();
              }
            });
          }

        });
      }

    }
  };
} // eslint-disable-next-line complexity


function applyMacros({
  path,
  imports,
  source,
  state,
  babel,
  interopRequire,
  resolvePath,
  options
}) {
  /* istanbul ignore next (pretty much only useful for astexplorer I think) */
  const {
    file: {
      opts: {
        filename = ''
      }
    }
  } = state;
  let hasReferences = false;
  const referencePathsByImportName = imports.reduce((byName, {
    importedName,
    localName
  }) => {
    const binding = path.scope.getBinding(localName);
    byName[importedName] = binding.referencePaths;
    hasReferences = hasReferences || Boolean(byName[importedName].length);
    return byName;
  }, {});
  const isRelative = source.indexOf('.') === 0;
  const requirePath = resolvePath(source, p.dirname(getFullFilename(filename)));
  const macro = interopRequire(requirePath);

  if (!macro.isBabelMacro) {
    throw new Error(`The macro imported from "${source}" must be wrapped in "createMacro" ` + `which you can get from "babel-plugin-macros". ` + `Please refer to the documentation to see how to do this properly: https://github.com/kentcdodds/babel-plugin-macros/blob/master/other/docs/author.md#writing-a-macro`);
  }

  const config = getConfig(macro, filename, source, options);
  let result;

  try {
    /**
     * Other plugins that run before babel-plugin-macros might use path.replace, where a path is
     * put into its own replacement. Apparently babel does not update the scope after such
     * an operation. As a remedy, the whole scope is traversed again with an empty "Identifier"
     * visitor - this makes the problem go away.
     *
     * See: https://github.com/kentcdodds/import-all.macro/issues/7
     */
    state.file.scope.path.traverse({
      Identifier() {}

    });
    result = macro({
      references: referencePathsByImportName,
      source,
      state,
      babel,
      config,
      isBabelMacrosCall: true
    });
  } catch (error) {
    if (error.name === 'MacroError') {
      throw error;
    }

    error.message = `${source}: ${error.message}`;

    if (!isRelative) {
      error.message = `${error.message} Learn more: https://www.npmjs.com/package/${source.replace( // remove everything after package name
      // @org/package/macro -> @org/package
      // package/macro      -> package
      /^((?:@[^/]+\/)?[^/]+).*/, '$1')}`;
    }

    throw error;
  }

  return result;
}

function getConfigFromFile(configName, filename) {
  try {
    const loaded = getConfigExplorer().search(filename);

    if (loaded) {
      return {
        options: loaded.config[configName],
        path: loaded.filepath
      };
    }
  } catch (e) {
    return {
      error: e
    };
  }

  return {};
}

function getConfigFromOptions(configName, options) {
  if (options.hasOwnProperty(configName)) {
    if (options[configName] && typeof options[configName] !== 'object') {
      // eslint-disable-next-line no-console
      console.error(`The macro plugin options' ${configName} property was not an object or null.`);
    } else {
      return {
        options: options[configName]
      };
    }
  }

  return {};
}

function getConfig(macro, filename, source, options) {
  const {
    configName
  } = macro.options;

  if (configName) {
    const fileConfig = getConfigFromFile(configName, filename);
    const optionsConfig = getConfigFromOptions(configName, options);

    if (optionsConfig.options === undefined && fileConfig.options === undefined && fileConfig.error !== undefined) {
      // eslint-disable-next-line no-console
      console.error(`There was an error trying to load the config "${configName}" ` + `for the macro imported from "${source}. ` + `Please see the error thrown for more information.`);
      throw fileConfig.error;
    }

    if (fileConfig.options !== undefined && optionsConfig.options !== undefined && typeof fileConfig.options !== 'object') {
      throw new Error(`${fileConfig.path} specified a ${configName} config of type ` + `${typeof optionsConfig.options}, but the the macros plugin's ` + `options.${configName} did contain an object. Both configs must ` + `contain objects for their options to be mergeable.`);
    }

    return { ...optionsConfig.options,
      ...fileConfig.options
    };
  }

  return undefined;
}
/*
 istanbul ignore next
 because this is hard to test
 and not worth it...
 */


function getFullFilename(filename) {
  if (p.isAbsolute(filename)) {
    return filename;
  }

  return p.join(process.cwd(), filename);
}

function looksLike(a, b) {
  return a && b && Object.keys(b).every(bKey => {
    const bVal = b[bKey];
    const aVal = a[bKey];

    if (typeof bVal === 'function') {
      return bVal(aVal);
    }

    return isPrimitive(bVal) ? bVal === aVal : looksLike(aVal, bVal);
  });
}

function isPrimitive(val) {
  // eslint-disable-next-line
  return val == null || /^[sbn]/.test(typeof val);
}

module.exports = macrosPlugin;
Object.assign(module.exports, {
  createMacro,
  MacroError
});