Function transform

packages/inject/src/index.js:87–207

(code, id)

    name: 'inject',

    transform(code, id) {
      if (!filter(id)) return null;
      if (code.search(firstpass) === -1) return null;

      if (sep !== '/') id = id.split(sep).join('/'); // eslint-disable-line no-param-reassign

      let ast = null;
      try {
        ast = this.parse(code);
      } catch (err) {
        this.warn({
          code: 'PARSE_ERROR',
          message: `@rollup/plugin-inject: failed to parse ${id}. Consider restricting the plugin to particular files via options.include`
        });
      }
      if (!ast) {
        return null;
      }

      const imports = new Set();
      ast.body.forEach((node) => {
        if (node.type === 'ImportDeclaration') {
          node.specifiers.forEach((specifier) => {
            imports.add(specifier.local.name);
          });
        }
      });

      // analyse scopes
      let scope = attachScopes(ast, 'scope');

      const magicString = new MagicString(code);

      const newImports = new Map();

      function handleReference(node, name, keypath) {
        let mod = modulesMap.get(keypath);
        if (mod && !imports.has(name) && !scope.contains(name)) {
          if (typeof mod === 'string') mod = [mod, 'default'];

          // prevent module from importing itself
          if (mod[0] === id) return false;

          const hash = `${keypath}:${mod[0]}:${mod[1]}`;

          const importLocalName =
            name === keypath ? name : makeLegalIdentifier(`$inject_${keypath}`);

          if (!newImports.has(hash)) {
            // escape apostrophes and backslashes for use in single-quoted string literal
            const modName = mod[0].replace(/[''\\]/g, '\\$&');
            if (mod[1] === '*') {
              newImports.set(hash, `import * as ${importLocalName} from '${modName}';`);
            } else {
              newImports.set(hash, `import { ${mod[1]} as ${importLocalName} } from '${modName}';`);
            }
          }