82 lines
1.8 KiB
JavaScript
82 lines
1.8 KiB
JavaScript
|
import {IS_IDENTIFIER_CHAR, IS_IDENTIFIER_START} from "../parser/util/identifier";
|
||
|
|
|
||
|
|
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar
|
||
|
|
// Hard-code a list of reserved words rather than trying to use keywords or contextual keywords
|
||
|
|
// from the parser, since currently there are various exceptions, like `package` being reserved
|
||
|
|
// but unused and various contextual keywords being reserved. Note that we assume that all code
|
||
|
|
// compiled by Sucrase is in a module, so strict mode words and await are all considered reserved
|
||
|
|
// here.
|
||
|
|
const RESERVED_WORDS = new Set([
|
||
|
|
// Reserved keywords as of ECMAScript 2015
|
||
|
|
"break",
|
||
|
|
"case",
|
||
|
|
"catch",
|
||
|
|
"class",
|
||
|
|
"const",
|
||
|
|
"continue",
|
||
|
|
"debugger",
|
||
|
|
"default",
|
||
|
|
"delete",
|
||
|
|
"do",
|
||
|
|
"else",
|
||
|
|
"export",
|
||
|
|
"extends",
|
||
|
|
"finally",
|
||
|
|
"for",
|
||
|
|
"function",
|
||
|
|
"if",
|
||
|
|
"import",
|
||
|
|
"in",
|
||
|
|
"instanceof",
|
||
|
|
"new",
|
||
|
|
"return",
|
||
|
|
"super",
|
||
|
|
"switch",
|
||
|
|
"this",
|
||
|
|
"throw",
|
||
|
|
"try",
|
||
|
|
"typeof",
|
||
|
|
"var",
|
||
|
|
"void",
|
||
|
|
"while",
|
||
|
|
"with",
|
||
|
|
"yield",
|
||
|
|
// Future reserved keywords
|
||
|
|
"enum",
|
||
|
|
"implements",
|
||
|
|
"interface",
|
||
|
|
"let",
|
||
|
|
"package",
|
||
|
|
"private",
|
||
|
|
"protected",
|
||
|
|
"public",
|
||
|
|
"static",
|
||
|
|
"await",
|
||
|
|
// Literals that cannot be used as identifiers
|
||
|
|
"false",
|
||
|
|
"null",
|
||
|
|
"true",
|
||
|
|
]);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Determine if the given name is a legal variable name.
|
||
|
|
*
|
||
|
|
* This is needed when transforming TypeScript enums; if an enum key is a valid
|
||
|
|
* variable name, it might be referenced later in the enum, so we need to
|
||
|
|
* declare a variable.
|
||
|
|
*/
|
||
|
|
export default function isIdentifier(name) {
|
||
|
|
if (name.length === 0) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
if (!IS_IDENTIFIER_START[name.charCodeAt(0)]) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
for (let i = 1; i < name.length; i++) {
|
||
|
|
if (!IS_IDENTIFIER_CHAR[name.charCodeAt(i)]) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return !RESERVED_WORDS.has(name);
|
||
|
|
}
|