forked from Fediversity/Fediversity
1005 lines
29 KiB
JavaScript
1005 lines
29 KiB
JavaScript
/* eslint max-len: 0 */
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import {input, isFlowEnabled, state} from "../traverser/base";
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import {unexpected} from "../traverser/util";
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import {charCodes} from "../util/charcodes";
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import {IS_IDENTIFIER_CHAR, IS_IDENTIFIER_START} from "../util/identifier";
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import {IS_WHITESPACE, skipWhiteSpace} from "../util/whitespace";
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import {ContextualKeyword} from "./keywords";
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import readWord from "./readWord";
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import { TokenType as tt} from "./types";
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export var IdentifierRole; (function (IdentifierRole) {
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const Access = 0; IdentifierRole[IdentifierRole["Access"] = Access] = "Access";
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const ExportAccess = Access + 1; IdentifierRole[IdentifierRole["ExportAccess"] = ExportAccess] = "ExportAccess";
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const TopLevelDeclaration = ExportAccess + 1; IdentifierRole[IdentifierRole["TopLevelDeclaration"] = TopLevelDeclaration] = "TopLevelDeclaration";
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const FunctionScopedDeclaration = TopLevelDeclaration + 1; IdentifierRole[IdentifierRole["FunctionScopedDeclaration"] = FunctionScopedDeclaration] = "FunctionScopedDeclaration";
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const BlockScopedDeclaration = FunctionScopedDeclaration + 1; IdentifierRole[IdentifierRole["BlockScopedDeclaration"] = BlockScopedDeclaration] = "BlockScopedDeclaration";
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const ObjectShorthandTopLevelDeclaration = BlockScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandTopLevelDeclaration"] = ObjectShorthandTopLevelDeclaration] = "ObjectShorthandTopLevelDeclaration";
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const ObjectShorthandFunctionScopedDeclaration = ObjectShorthandTopLevelDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandFunctionScopedDeclaration"] = ObjectShorthandFunctionScopedDeclaration] = "ObjectShorthandFunctionScopedDeclaration";
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const ObjectShorthandBlockScopedDeclaration = ObjectShorthandFunctionScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandBlockScopedDeclaration"] = ObjectShorthandBlockScopedDeclaration] = "ObjectShorthandBlockScopedDeclaration";
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const ObjectShorthand = ObjectShorthandBlockScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthand"] = ObjectShorthand] = "ObjectShorthand";
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// Any identifier bound in an import statement, e.g. both A and b from
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// `import A, * as b from 'A';`
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const ImportDeclaration = ObjectShorthand + 1; IdentifierRole[IdentifierRole["ImportDeclaration"] = ImportDeclaration] = "ImportDeclaration";
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const ObjectKey = ImportDeclaration + 1; IdentifierRole[IdentifierRole["ObjectKey"] = ObjectKey] = "ObjectKey";
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// The `foo` in `import {foo as bar} from "./abc";`.
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const ImportAccess = ObjectKey + 1; IdentifierRole[IdentifierRole["ImportAccess"] = ImportAccess] = "ImportAccess";
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})(IdentifierRole || (IdentifierRole = {}));
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/**
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* Extra information on jsxTagStart tokens, used to determine which of the three
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* jsx functions are called in the automatic transform.
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*/
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export var JSXRole; (function (JSXRole) {
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// The element is self-closing or has a body that resolves to empty. We
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// shouldn't emit children at all in this case.
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const NoChildren = 0; JSXRole[JSXRole["NoChildren"] = NoChildren] = "NoChildren";
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// The element has a single explicit child, which might still be an arbitrary
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// expression like an array. We should emit that expression as the children.
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const OneChild = NoChildren + 1; JSXRole[JSXRole["OneChild"] = OneChild] = "OneChild";
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// The element has at least two explicitly-specified children or has spread
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// children, so child positions are assumed to be "static". We should wrap
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// these children in an array.
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const StaticChildren = OneChild + 1; JSXRole[JSXRole["StaticChildren"] = StaticChildren] = "StaticChildren";
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// The element has a prop named "key" after a prop spread, so we should fall
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// back to the createElement function.
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const KeyAfterPropSpread = StaticChildren + 1; JSXRole[JSXRole["KeyAfterPropSpread"] = KeyAfterPropSpread] = "KeyAfterPropSpread";
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})(JSXRole || (JSXRole = {}));
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export function isDeclaration(token) {
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const role = token.identifierRole;
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return (
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role === IdentifierRole.TopLevelDeclaration ||
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role === IdentifierRole.FunctionScopedDeclaration ||
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role === IdentifierRole.BlockScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
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role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
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);
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}
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export function isNonTopLevelDeclaration(token) {
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const role = token.identifierRole;
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return (
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role === IdentifierRole.FunctionScopedDeclaration ||
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role === IdentifierRole.BlockScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
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);
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}
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export function isTopLevelDeclaration(token) {
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const role = token.identifierRole;
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return (
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role === IdentifierRole.TopLevelDeclaration ||
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role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
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role === IdentifierRole.ImportDeclaration
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);
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}
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export function isBlockScopedDeclaration(token) {
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const role = token.identifierRole;
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// Treat top-level declarations as block scope since the distinction doesn't matter here.
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return (
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role === IdentifierRole.TopLevelDeclaration ||
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role === IdentifierRole.BlockScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
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role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
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);
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}
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export function isFunctionScopedDeclaration(token) {
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const role = token.identifierRole;
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return (
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role === IdentifierRole.FunctionScopedDeclaration ||
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role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration
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);
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}
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export function isObjectShorthandDeclaration(token) {
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return (
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token.identifierRole === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
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token.identifierRole === IdentifierRole.ObjectShorthandBlockScopedDeclaration ||
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token.identifierRole === IdentifierRole.ObjectShorthandFunctionScopedDeclaration
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);
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}
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// Object type used to represent tokens. Note that normally, tokens
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// simply exist as properties on the parser object. This is only
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// used for the onToken callback and the external tokenizer.
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export class Token {
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constructor() {
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this.type = state.type;
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this.contextualKeyword = state.contextualKeyword;
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this.start = state.start;
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this.end = state.end;
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this.scopeDepth = state.scopeDepth;
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this.isType = state.isType;
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this.identifierRole = null;
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this.jsxRole = null;
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this.shadowsGlobal = false;
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this.isAsyncOperation = false;
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this.contextId = null;
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this.rhsEndIndex = null;
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this.isExpression = false;
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this.numNullishCoalesceStarts = 0;
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this.numNullishCoalesceEnds = 0;
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this.isOptionalChainStart = false;
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this.isOptionalChainEnd = false;
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this.subscriptStartIndex = null;
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this.nullishStartIndex = null;
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}
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// Initially false for all tokens, then may be computed in a follow-up step that does scope
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// analysis.
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// Initially false for all tokens, but may be set during transform to mark it as containing an
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// await operation.
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// For assignments, the index of the RHS. For export tokens, the end of the export.
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// For class tokens, records if the class is a class expression or a class statement.
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// Number of times to insert a `nullishCoalesce(` snippet before this token.
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// Number of times to insert a `)` snippet after this token.
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// If true, insert an `optionalChain([` snippet before this token.
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// If true, insert a `])` snippet after this token.
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// Tag for `.`, `?.`, `[`, `?.[`, `(`, and `?.(` to denote the "root" token for this
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// subscript chain. This can be used to determine if this chain is an optional chain.
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// Tag for `??` operators to denote the root token for this nullish coalescing call.
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}
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// ## Tokenizer
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// Move to the next token
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export function next() {
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state.tokens.push(new Token());
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nextToken();
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}
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// Call instead of next when inside a template, since that needs to be handled differently.
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export function nextTemplateToken() {
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state.tokens.push(new Token());
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state.start = state.pos;
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readTmplToken();
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}
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// The tokenizer never parses regexes by default. Instead, the parser is responsible for
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// instructing it to parse a regex when we see a slash at the start of an expression.
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export function retokenizeSlashAsRegex() {
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if (state.type === tt.assign) {
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--state.pos;
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}
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readRegexp();
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}
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export function pushTypeContext(existingTokensInType) {
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for (let i = state.tokens.length - existingTokensInType; i < state.tokens.length; i++) {
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state.tokens[i].isType = true;
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}
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const oldIsType = state.isType;
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state.isType = true;
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return oldIsType;
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}
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export function popTypeContext(oldIsType) {
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state.isType = oldIsType;
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}
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export function eat(type) {
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if (match(type)) {
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next();
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return true;
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} else {
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return false;
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}
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}
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export function eatTypeToken(tokenType) {
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const oldIsType = state.isType;
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state.isType = true;
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eat(tokenType);
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state.isType = oldIsType;
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}
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export function match(type) {
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return state.type === type;
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}
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export function lookaheadType() {
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const snapshot = state.snapshot();
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next();
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const type = state.type;
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state.restoreFromSnapshot(snapshot);
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return type;
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}
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export class TypeAndKeyword {
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constructor(type, contextualKeyword) {
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this.type = type;
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this.contextualKeyword = contextualKeyword;
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}
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}
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export function lookaheadTypeAndKeyword() {
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const snapshot = state.snapshot();
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next();
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const type = state.type;
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const contextualKeyword = state.contextualKeyword;
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state.restoreFromSnapshot(snapshot);
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return new TypeAndKeyword(type, contextualKeyword);
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}
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export function nextTokenStart() {
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return nextTokenStartSince(state.pos);
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}
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export function nextTokenStartSince(pos) {
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skipWhiteSpace.lastIndex = pos;
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const skip = skipWhiteSpace.exec(input);
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return pos + skip[0].length;
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}
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export function lookaheadCharCode() {
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return input.charCodeAt(nextTokenStart());
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}
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// Read a single token, updating the parser object's token-related
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// properties.
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export function nextToken() {
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skipSpace();
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state.start = state.pos;
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if (state.pos >= input.length) {
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const tokens = state.tokens;
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// We normally run past the end a bit, but if we're way past the end, avoid an infinite loop.
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// Also check the token positions rather than the types since sometimes we rewrite the token
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// type to something else.
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if (
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tokens.length >= 2 &&
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tokens[tokens.length - 1].start >= input.length &&
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tokens[tokens.length - 2].start >= input.length
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) {
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unexpected("Unexpectedly reached the end of input.");
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}
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finishToken(tt.eof);
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return;
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}
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readToken(input.charCodeAt(state.pos));
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}
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function readToken(code) {
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// Identifier or keyword. '\uXXXX' sequences are allowed in
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// identifiers, so '\' also dispatches to that.
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if (
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IS_IDENTIFIER_START[code] ||
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code === charCodes.backslash ||
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(code === charCodes.atSign && input.charCodeAt(state.pos + 1) === charCodes.atSign)
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) {
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readWord();
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} else {
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getTokenFromCode(code);
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}
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}
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function skipBlockComment() {
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while (
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input.charCodeAt(state.pos) !== charCodes.asterisk ||
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input.charCodeAt(state.pos + 1) !== charCodes.slash
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) {
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state.pos++;
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if (state.pos > input.length) {
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unexpected("Unterminated comment", state.pos - 2);
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return;
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}
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}
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state.pos += 2;
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}
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export function skipLineComment(startSkip) {
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let ch = input.charCodeAt((state.pos += startSkip));
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if (state.pos < input.length) {
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while (
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ch !== charCodes.lineFeed &&
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ch !== charCodes.carriageReturn &&
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ch !== charCodes.lineSeparator &&
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ch !== charCodes.paragraphSeparator &&
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++state.pos < input.length
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) {
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ch = input.charCodeAt(state.pos);
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}
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}
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}
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// Called at the start of the parse and after every token. Skips
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// whitespace and comments.
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export function skipSpace() {
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while (state.pos < input.length) {
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const ch = input.charCodeAt(state.pos);
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switch (ch) {
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case charCodes.carriageReturn:
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if (input.charCodeAt(state.pos + 1) === charCodes.lineFeed) {
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++state.pos;
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}
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case charCodes.lineFeed:
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case charCodes.lineSeparator:
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case charCodes.paragraphSeparator:
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++state.pos;
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break;
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case charCodes.slash:
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switch (input.charCodeAt(state.pos + 1)) {
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case charCodes.asterisk:
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state.pos += 2;
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skipBlockComment();
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break;
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case charCodes.slash:
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skipLineComment(2);
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break;
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default:
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return;
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}
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break;
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default:
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if (IS_WHITESPACE[ch]) {
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++state.pos;
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} else {
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return;
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}
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}
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}
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}
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// Called at the end of every token. Sets various fields, and skips the space after the token, so
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// that the next one's `start` will point at the right position.
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export function finishToken(
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type,
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contextualKeyword = ContextualKeyword.NONE,
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) {
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state.end = state.pos;
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state.type = type;
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state.contextualKeyword = contextualKeyword;
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}
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// ### Token reading
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// This is the function that is called to fetch the next token. It
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// is somewhat obscure, because it works in character codes rather
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// than characters, and because operator parsing has been inlined
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// into it.
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//
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// All in the name of speed.
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function readToken_dot() {
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar >= charCodes.digit0 && nextChar <= charCodes.digit9) {
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readNumber(true);
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return;
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}
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if (nextChar === charCodes.dot && input.charCodeAt(state.pos + 2) === charCodes.dot) {
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state.pos += 3;
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finishToken(tt.ellipsis);
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} else {
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++state.pos;
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finishToken(tt.dot);
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}
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}
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function readToken_slash() {
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar === charCodes.equalsTo) {
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finishOp(tt.assign, 2);
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} else {
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finishOp(tt.slash, 1);
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}
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}
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function readToken_mult_modulo(code) {
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// '%*'
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let tokenType = code === charCodes.asterisk ? tt.star : tt.modulo;
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let width = 1;
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let nextChar = input.charCodeAt(state.pos + 1);
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// Exponentiation operator **
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if (code === charCodes.asterisk && nextChar === charCodes.asterisk) {
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width++;
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nextChar = input.charCodeAt(state.pos + 2);
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tokenType = tt.exponent;
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}
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// Match *= or %=, disallowing *=> which can be valid in flow.
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if (
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nextChar === charCodes.equalsTo &&
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input.charCodeAt(state.pos + 2) !== charCodes.greaterThan
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) {
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width++;
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tokenType = tt.assign;
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}
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finishOp(tokenType, width);
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}
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function readToken_pipe_amp(code) {
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// '|&'
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar === code) {
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if (input.charCodeAt(state.pos + 2) === charCodes.equalsTo) {
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// ||= or &&=
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finishOp(tt.assign, 3);
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} else {
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// || or &&
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finishOp(code === charCodes.verticalBar ? tt.logicalOR : tt.logicalAND, 2);
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}
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return;
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}
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if (code === charCodes.verticalBar) {
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// '|>'
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if (nextChar === charCodes.greaterThan) {
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finishOp(tt.pipeline, 2);
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return;
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} else if (nextChar === charCodes.rightCurlyBrace && isFlowEnabled) {
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// '|}'
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finishOp(tt.braceBarR, 2);
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return;
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}
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}
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if (nextChar === charCodes.equalsTo) {
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finishOp(tt.assign, 2);
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return;
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}
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finishOp(code === charCodes.verticalBar ? tt.bitwiseOR : tt.bitwiseAND, 1);
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}
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function readToken_caret() {
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// '^'
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar === charCodes.equalsTo) {
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finishOp(tt.assign, 2);
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} else {
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finishOp(tt.bitwiseXOR, 1);
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}
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}
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function readToken_plus_min(code) {
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// '+-'
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar === code) {
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// Tentatively call this a prefix operator, but it might be changed to postfix later.
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finishOp(tt.preIncDec, 2);
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return;
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}
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if (nextChar === charCodes.equalsTo) {
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finishOp(tt.assign, 2);
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} else if (code === charCodes.plusSign) {
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finishOp(tt.plus, 1);
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} else {
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finishOp(tt.minus, 1);
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}
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}
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function readToken_lt() {
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const nextChar = input.charCodeAt(state.pos + 1);
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if (nextChar === charCodes.lessThan) {
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if (input.charCodeAt(state.pos + 2) === charCodes.equalsTo) {
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finishOp(tt.assign, 3);
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return;
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}
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// We see <<, but need to be really careful about whether to treat it as a
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// true left-shift or as two < tokens.
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if (state.isType) {
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// Within a type, << might come up in a snippet like `Array<<T>() => void>`,
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// so treat it as two < tokens. Importantly, this should only override <<
|
|
// rather than other tokens like <= . If we treated <= as < in a type
|
|
// context, then the snippet `a as T <= 1` would incorrectly start parsing
|
|
// a type argument on T. We don't need to worry about `a as T << 1`
|
|
// because TypeScript disallows that syntax.
|
|
finishOp(tt.lessThan, 1);
|
|
} else {
|
|
// Outside a type, this might be a true left-shift operator, or it might
|
|
// still be two open-type-arg tokens, such as in `f<<T>() => void>()`. We
|
|
// look at the token while considering the `f`, so we don't yet know that
|
|
// we're in a type context. In this case, we initially tokenize as a
|
|
// left-shift and correct after-the-fact as necessary in
|
|
// tsParseTypeArgumentsWithPossibleBitshift .
|
|
finishOp(tt.bitShiftL, 2);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (nextChar === charCodes.equalsTo) {
|
|
// <=
|
|
finishOp(tt.relationalOrEqual, 2);
|
|
} else {
|
|
finishOp(tt.lessThan, 1);
|
|
}
|
|
}
|
|
|
|
function readToken_gt() {
|
|
if (state.isType) {
|
|
// Avoid right-shift for things like `Array<Array<string>>` and
|
|
// greater-than-or-equal for things like `const a: Array<number>=[];`.
|
|
finishOp(tt.greaterThan, 1);
|
|
return;
|
|
}
|
|
|
|
const nextChar = input.charCodeAt(state.pos + 1);
|
|
|
|
if (nextChar === charCodes.greaterThan) {
|
|
const size = input.charCodeAt(state.pos + 2) === charCodes.greaterThan ? 3 : 2;
|
|
if (input.charCodeAt(state.pos + size) === charCodes.equalsTo) {
|
|
finishOp(tt.assign, size + 1);
|
|
return;
|
|
}
|
|
finishOp(tt.bitShiftR, size);
|
|
return;
|
|
}
|
|
|
|
if (nextChar === charCodes.equalsTo) {
|
|
// >=
|
|
finishOp(tt.relationalOrEqual, 2);
|
|
} else {
|
|
finishOp(tt.greaterThan, 1);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Reinterpret a possible > token when transitioning from a type to a non-type
|
|
* context.
|
|
*
|
|
* This comes up in two situations where >= needs to be treated as one token:
|
|
* - After an `as` expression, like in the code `a as T >= 1`.
|
|
* - In a type argument in an expression context, e.g. `f(a < b, c >= d)`, we
|
|
* need to see the token as >= so that we get an error and backtrack to
|
|
* normal expression parsing.
|
|
*
|
|
* Other situations require >= to be seen as two tokens, e.g.
|
|
* `const x: Array<T>=[];`, so it's important to treat > as its own token in
|
|
* typical type parsing situations.
|
|
*/
|
|
export function rescan_gt() {
|
|
if (state.type === tt.greaterThan) {
|
|
state.pos -= 1;
|
|
readToken_gt();
|
|
}
|
|
}
|
|
|
|
function readToken_eq_excl(code) {
|
|
// '=!'
|
|
const nextChar = input.charCodeAt(state.pos + 1);
|
|
if (nextChar === charCodes.equalsTo) {
|
|
finishOp(tt.equality, input.charCodeAt(state.pos + 2) === charCodes.equalsTo ? 3 : 2);
|
|
return;
|
|
}
|
|
if (code === charCodes.equalsTo && nextChar === charCodes.greaterThan) {
|
|
// '=>'
|
|
state.pos += 2;
|
|
finishToken(tt.arrow);
|
|
return;
|
|
}
|
|
finishOp(code === charCodes.equalsTo ? tt.eq : tt.bang, 1);
|
|
}
|
|
|
|
function readToken_question() {
|
|
// '?'
|
|
const nextChar = input.charCodeAt(state.pos + 1);
|
|
const nextChar2 = input.charCodeAt(state.pos + 2);
|
|
if (
|
|
nextChar === charCodes.questionMark &&
|
|
// In Flow (but not TypeScript), ??string is a valid type that should be
|
|
// tokenized as two individual ? tokens.
|
|
!(isFlowEnabled && state.isType)
|
|
) {
|
|
if (nextChar2 === charCodes.equalsTo) {
|
|
// '??='
|
|
finishOp(tt.assign, 3);
|
|
} else {
|
|
// '??'
|
|
finishOp(tt.nullishCoalescing, 2);
|
|
}
|
|
} else if (
|
|
nextChar === charCodes.dot &&
|
|
!(nextChar2 >= charCodes.digit0 && nextChar2 <= charCodes.digit9)
|
|
) {
|
|
// '.' not followed by a number
|
|
state.pos += 2;
|
|
finishToken(tt.questionDot);
|
|
} else {
|
|
++state.pos;
|
|
finishToken(tt.question);
|
|
}
|
|
}
|
|
|
|
export function getTokenFromCode(code) {
|
|
switch (code) {
|
|
case charCodes.numberSign:
|
|
++state.pos;
|
|
finishToken(tt.hash);
|
|
return;
|
|
|
|
// The interpretation of a dot depends on whether it is followed
|
|
// by a digit or another two dots.
|
|
|
|
case charCodes.dot:
|
|
readToken_dot();
|
|
return;
|
|
|
|
// Punctuation tokens.
|
|
case charCodes.leftParenthesis:
|
|
++state.pos;
|
|
finishToken(tt.parenL);
|
|
return;
|
|
case charCodes.rightParenthesis:
|
|
++state.pos;
|
|
finishToken(tt.parenR);
|
|
return;
|
|
case charCodes.semicolon:
|
|
++state.pos;
|
|
finishToken(tt.semi);
|
|
return;
|
|
case charCodes.comma:
|
|
++state.pos;
|
|
finishToken(tt.comma);
|
|
return;
|
|
case charCodes.leftSquareBracket:
|
|
++state.pos;
|
|
finishToken(tt.bracketL);
|
|
return;
|
|
case charCodes.rightSquareBracket:
|
|
++state.pos;
|
|
finishToken(tt.bracketR);
|
|
return;
|
|
|
|
case charCodes.leftCurlyBrace:
|
|
if (isFlowEnabled && input.charCodeAt(state.pos + 1) === charCodes.verticalBar) {
|
|
finishOp(tt.braceBarL, 2);
|
|
} else {
|
|
++state.pos;
|
|
finishToken(tt.braceL);
|
|
}
|
|
return;
|
|
|
|
case charCodes.rightCurlyBrace:
|
|
++state.pos;
|
|
finishToken(tt.braceR);
|
|
return;
|
|
|
|
case charCodes.colon:
|
|
if (input.charCodeAt(state.pos + 1) === charCodes.colon) {
|
|
finishOp(tt.doubleColon, 2);
|
|
} else {
|
|
++state.pos;
|
|
finishToken(tt.colon);
|
|
}
|
|
return;
|
|
|
|
case charCodes.questionMark:
|
|
readToken_question();
|
|
return;
|
|
case charCodes.atSign:
|
|
++state.pos;
|
|
finishToken(tt.at);
|
|
return;
|
|
|
|
case charCodes.graveAccent:
|
|
++state.pos;
|
|
finishToken(tt.backQuote);
|
|
return;
|
|
|
|
case charCodes.digit0: {
|
|
const nextChar = input.charCodeAt(state.pos + 1);
|
|
// '0x', '0X', '0o', '0O', '0b', '0B'
|
|
if (
|
|
nextChar === charCodes.lowercaseX ||
|
|
nextChar === charCodes.uppercaseX ||
|
|
nextChar === charCodes.lowercaseO ||
|
|
nextChar === charCodes.uppercaseO ||
|
|
nextChar === charCodes.lowercaseB ||
|
|
nextChar === charCodes.uppercaseB
|
|
) {
|
|
readRadixNumber();
|
|
return;
|
|
}
|
|
}
|
|
// Anything else beginning with a digit is an integer, octal
|
|
// number, or float.
|
|
case charCodes.digit1:
|
|
case charCodes.digit2:
|
|
case charCodes.digit3:
|
|
case charCodes.digit4:
|
|
case charCodes.digit5:
|
|
case charCodes.digit6:
|
|
case charCodes.digit7:
|
|
case charCodes.digit8:
|
|
case charCodes.digit9:
|
|
readNumber(false);
|
|
return;
|
|
|
|
// Quotes produce strings.
|
|
case charCodes.quotationMark:
|
|
case charCodes.apostrophe:
|
|
readString(code);
|
|
return;
|
|
|
|
// Operators are parsed inline in tiny state machines. '=' (charCodes.equalsTo) is
|
|
// often referred to. `finishOp` simply skips the amount of
|
|
// characters it is given as second argument, and returns a token
|
|
// of the type given by its first argument.
|
|
|
|
case charCodes.slash:
|
|
readToken_slash();
|
|
return;
|
|
|
|
case charCodes.percentSign:
|
|
case charCodes.asterisk:
|
|
readToken_mult_modulo(code);
|
|
return;
|
|
|
|
case charCodes.verticalBar:
|
|
case charCodes.ampersand:
|
|
readToken_pipe_amp(code);
|
|
return;
|
|
|
|
case charCodes.caret:
|
|
readToken_caret();
|
|
return;
|
|
|
|
case charCodes.plusSign:
|
|
case charCodes.dash:
|
|
readToken_plus_min(code);
|
|
return;
|
|
|
|
case charCodes.lessThan:
|
|
readToken_lt();
|
|
return;
|
|
|
|
case charCodes.greaterThan:
|
|
readToken_gt();
|
|
return;
|
|
|
|
case charCodes.equalsTo:
|
|
case charCodes.exclamationMark:
|
|
readToken_eq_excl(code);
|
|
return;
|
|
|
|
case charCodes.tilde:
|
|
finishOp(tt.tilde, 1);
|
|
return;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
unexpected(`Unexpected character '${String.fromCharCode(code)}'`, state.pos);
|
|
}
|
|
|
|
function finishOp(type, size) {
|
|
state.pos += size;
|
|
finishToken(type);
|
|
}
|
|
|
|
function readRegexp() {
|
|
const start = state.pos;
|
|
let escaped = false;
|
|
let inClass = false;
|
|
for (;;) {
|
|
if (state.pos >= input.length) {
|
|
unexpected("Unterminated regular expression", start);
|
|
return;
|
|
}
|
|
const code = input.charCodeAt(state.pos);
|
|
if (escaped) {
|
|
escaped = false;
|
|
} else {
|
|
if (code === charCodes.leftSquareBracket) {
|
|
inClass = true;
|
|
} else if (code === charCodes.rightSquareBracket && inClass) {
|
|
inClass = false;
|
|
} else if (code === charCodes.slash && !inClass) {
|
|
break;
|
|
}
|
|
escaped = code === charCodes.backslash;
|
|
}
|
|
++state.pos;
|
|
}
|
|
++state.pos;
|
|
// Need to use `skipWord` because '\uXXXX' sequences are allowed here (don't ask).
|
|
skipWord();
|
|
|
|
finishToken(tt.regexp);
|
|
}
|
|
|
|
/**
|
|
* Read a decimal integer. Note that this can't be unified with the similar code
|
|
* in readRadixNumber (which also handles hex digits) because "e" needs to be
|
|
* the end of the integer so that we can properly handle scientific notation.
|
|
*/
|
|
function readInt() {
|
|
while (true) {
|
|
const code = input.charCodeAt(state.pos);
|
|
if ((code >= charCodes.digit0 && code <= charCodes.digit9) || code === charCodes.underscore) {
|
|
state.pos++;
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
function readRadixNumber() {
|
|
state.pos += 2; // 0x
|
|
|
|
// Walk to the end of the number, allowing hex digits.
|
|
while (true) {
|
|
const code = input.charCodeAt(state.pos);
|
|
if (
|
|
(code >= charCodes.digit0 && code <= charCodes.digit9) ||
|
|
(code >= charCodes.lowercaseA && code <= charCodes.lowercaseF) ||
|
|
(code >= charCodes.uppercaseA && code <= charCodes.uppercaseF) ||
|
|
code === charCodes.underscore
|
|
) {
|
|
state.pos++;
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
|
|
const nextChar = input.charCodeAt(state.pos);
|
|
if (nextChar === charCodes.lowercaseN) {
|
|
++state.pos;
|
|
finishToken(tt.bigint);
|
|
} else {
|
|
finishToken(tt.num);
|
|
}
|
|
}
|
|
|
|
// Read an integer, octal integer, or floating-point number.
|
|
function readNumber(startsWithDot) {
|
|
let isBigInt = false;
|
|
let isDecimal = false;
|
|
|
|
if (!startsWithDot) {
|
|
readInt();
|
|
}
|
|
|
|
let nextChar = input.charCodeAt(state.pos);
|
|
if (nextChar === charCodes.dot) {
|
|
++state.pos;
|
|
readInt();
|
|
nextChar = input.charCodeAt(state.pos);
|
|
}
|
|
|
|
if (nextChar === charCodes.uppercaseE || nextChar === charCodes.lowercaseE) {
|
|
nextChar = input.charCodeAt(++state.pos);
|
|
if (nextChar === charCodes.plusSign || nextChar === charCodes.dash) {
|
|
++state.pos;
|
|
}
|
|
readInt();
|
|
nextChar = input.charCodeAt(state.pos);
|
|
}
|
|
|
|
if (nextChar === charCodes.lowercaseN) {
|
|
++state.pos;
|
|
isBigInt = true;
|
|
} else if (nextChar === charCodes.lowercaseM) {
|
|
++state.pos;
|
|
isDecimal = true;
|
|
}
|
|
|
|
if (isBigInt) {
|
|
finishToken(tt.bigint);
|
|
return;
|
|
}
|
|
|
|
if (isDecimal) {
|
|
finishToken(tt.decimal);
|
|
return;
|
|
}
|
|
|
|
finishToken(tt.num);
|
|
}
|
|
|
|
function readString(quote) {
|
|
state.pos++;
|
|
for (;;) {
|
|
if (state.pos >= input.length) {
|
|
unexpected("Unterminated string constant");
|
|
return;
|
|
}
|
|
const ch = input.charCodeAt(state.pos);
|
|
if (ch === charCodes.backslash) {
|
|
state.pos++;
|
|
} else if (ch === quote) {
|
|
break;
|
|
}
|
|
state.pos++;
|
|
}
|
|
state.pos++;
|
|
finishToken(tt.string);
|
|
}
|
|
|
|
// Reads template string tokens.
|
|
function readTmplToken() {
|
|
for (;;) {
|
|
if (state.pos >= input.length) {
|
|
unexpected("Unterminated template");
|
|
return;
|
|
}
|
|
const ch = input.charCodeAt(state.pos);
|
|
if (
|
|
ch === charCodes.graveAccent ||
|
|
(ch === charCodes.dollarSign && input.charCodeAt(state.pos + 1) === charCodes.leftCurlyBrace)
|
|
) {
|
|
if (state.pos === state.start && match(tt.template)) {
|
|
if (ch === charCodes.dollarSign) {
|
|
state.pos += 2;
|
|
finishToken(tt.dollarBraceL);
|
|
return;
|
|
} else {
|
|
++state.pos;
|
|
finishToken(tt.backQuote);
|
|
return;
|
|
}
|
|
}
|
|
finishToken(tt.template);
|
|
return;
|
|
}
|
|
if (ch === charCodes.backslash) {
|
|
state.pos++;
|
|
}
|
|
state.pos++;
|
|
}
|
|
}
|
|
|
|
// Skip to the end of the current word. Note that this is the same as the snippet at the end of
|
|
// readWord, but calling skipWord from readWord seems to slightly hurt performance from some rough
|
|
// measurements.
|
|
export function skipWord() {
|
|
while (state.pos < input.length) {
|
|
const ch = input.charCodeAt(state.pos);
|
|
if (IS_IDENTIFIER_CHAR[ch]) {
|
|
state.pos++;
|
|
} else if (ch === charCodes.backslash) {
|
|
// \u
|
|
state.pos += 2;
|
|
if (input.charCodeAt(state.pos) === charCodes.leftCurlyBrace) {
|
|
while (
|
|
state.pos < input.length &&
|
|
input.charCodeAt(state.pos) !== charCodes.rightCurlyBrace
|
|
) {
|
|
state.pos++;
|
|
}
|
|
state.pos++;
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|