node_modules/recast/lib/parser.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.parse = void 0;
var tslib_1 = require("tslib");
var assert_1 = tslib_1.__importDefault(require("assert"));
var types = tslib_1.__importStar(require("ast-types"));
var b = types.builders;
var isObject = types.builtInTypes.object;
var isArray = types.builtInTypes.array;
var options_1 = require("./options");
var lines_1 = require("./lines");
var comments_1 = require("./comments");
var util = tslib_1.__importStar(require("./util"));
function parse(source, options) {
    options = options_1.normalize(options);
    var lines = lines_1.fromString(source, options);
    var sourceWithoutTabs = lines.toString({
        tabWidth: options.tabWidth,
        reuseWhitespace: false,
        useTabs: false,
    });
    var comments = [];
    var ast = options.parser.parse(sourceWithoutTabs, {
        jsx: true,
        loc: true,
        locations: true,
        range: options.range,
        comment: true,
        onComment: comments,
        tolerant: util.getOption(options, "tolerant", true),
        ecmaVersion: 6,
        sourceType: util.getOption(options, "sourceType", "module"),
    });
    // Use ast.tokens if possible, and otherwise fall back to the Esprima
    // tokenizer. All the preconfigured ../parsers/* expose ast.tokens
    // automatically, but custom parsers might need additional configuration
    // to avoid this fallback.
    var tokens = Array.isArray(ast.tokens)
        ? ast.tokens
        : require("esprima").tokenize(sourceWithoutTabs, {
            loc: true,
        });
    // We will reattach the tokens array to the file object below.
    delete ast.tokens;
    // Make sure every token has a token.value string.
    tokens.forEach(function (token) {
        if (typeof token.value !== "string") {
            token.value = lines.sliceString(token.loc.start, token.loc.end);
        }
    });
    if (Array.isArray(ast.comments)) {
        comments = ast.comments;
        delete ast.comments;
    }
    if (ast.loc) {
        // If the source was empty, some parsers give loc.{start,end}.line
        // values of 0, instead of the minimum of 1.
        util.fixFaultyLocations(ast, lines);
    }
    else {
        ast.loc = {
            start: lines.firstPos(),
            end: lines.lastPos(),
        };
    }
    ast.loc.lines = lines;
    ast.loc.indent = 0;
    var file;
    var program;
    if (ast.type === "Program") {
        program = ast;
        // In order to ensure we reprint leading and trailing program
        // comments, wrap the original Program node with a File node. Only
        // ESTree parsers (Acorn and Esprima) return a Program as the root AST
        // node. Most other (Babylon-like) parsers return a File.
        file = b.file(ast, options.sourceFileName || null);
        file.loc = {
            start: lines.firstPos(),
            end: lines.lastPos(),
            lines: lines,
            indent: 0,
        };
    }
    else if (ast.type === "File") {
        file = ast;
        program = file.program;
    }
    // Expose file.tokens unless the caller passed false for options.tokens.
    if (options.tokens) {
        file.tokens = tokens;
    }
    // Expand the Program's .loc to include all comments (not just those
    // attached to the Program node, as its children may have comments as
    // well), since sometimes program.loc.{start,end} will coincide with the
    // .loc.{start,end} of the first and last *statements*, mistakenly
    // excluding comments that fall outside that region.
    var trueProgramLoc = util.getTrueLoc({
        type: program.type,
        loc: program.loc,
        body: [],
        comments: comments,
    }, lines);
    program.loc.start = trueProgramLoc.start;
    program.loc.end = trueProgramLoc.end;
    // Passing file.program here instead of just file means that initial
    // comments will be attached to program.body[0] instead of program.
    comments_1.attach(comments, program.body.length ? file.program : file, lines);
    // Return a copy of the original AST so that any changes made may be
    // compared to the original.
    return new TreeCopier(lines, tokens).copy(file);
}
exports.parse = parse;
var TreeCopier = function TreeCopier(lines, tokens) {
    assert_1.default.ok(this instanceof TreeCopier);
    this.lines = lines;
    this.tokens = tokens;
    this.startTokenIndex = 0;
    this.endTokenIndex = tokens.length;
    this.indent = 0;
    this.seen = new Map();
};
var TCp = TreeCopier.prototype;
TCp.copy = function (node) {
    if (this.seen.has(node)) {
        return this.seen.get(node);
    }
    if (isArray.check(node)) {
        var copy_1 = new Array(node.length);
        this.seen.set(node, copy_1);
        node.forEach(function (item, i) {
            copy_1[i] = this.copy(item);
        }, this);
        return copy_1;
    }
    if (!isObject.check(node)) {
        return node;
    }
    util.fixFaultyLocations(node, this.lines);
    var copy = Object.create(Object.getPrototypeOf(node), {
        original: {
            // Provide a link from the copy to the original.
            value: node,
            configurable: false,
            enumerable: false,
            writable: true,
        },
    });
    this.seen.set(node, copy);
    var loc = node.loc;
    var oldIndent = this.indent;
    var newIndent = oldIndent;
    var oldStartTokenIndex = this.startTokenIndex;
    var oldEndTokenIndex = this.endTokenIndex;
    if (loc) {
        // When node is a comment, we set node.loc.indent to
        // node.loc.start.column so that, when/if we print the comment by
        // itself, we can strip that much whitespace from the left margin of
        // the comment. This only really matters for multiline Block comments,
        // but it doesn't hurt for Line comments.
        if (node.type === "Block" ||
            node.type === "Line" ||
            node.type === "CommentBlock" ||
            node.type === "CommentLine" ||
            this.lines.isPrecededOnlyByWhitespace(loc.start)) {
            newIndent = this.indent = loc.start.column;
        }
        // Every node.loc has a reference to the original source lines as well
        // as a complete list of source tokens.
        loc.lines = this.lines;
        loc.tokens = this.tokens;
        loc.indent = newIndent;
        // Set loc.start.token and loc.end.token such that
        // loc.tokens.slice(loc.start.token, loc.end.token) returns a list of
        // all the tokens that make up this node.
        this.findTokenRange(loc);
    }
    var keys = Object.keys(node);
    var keyCount = keys.length;
    for (var i = 0; i < keyCount; ++i) {
        var key = keys[i];
        if (key === "loc") {
            copy[key] = node[key];
        }
        else if (key === "tokens" && node.type === "File") {
            // Preserve file.tokens (uncopied) in case client code cares about
            // it, even though Recast ignores it when reprinting.
            copy[key] = node[key];
        }
        else {
            copy[key] = this.copy(node[key]);
        }
    }
    this.indent = oldIndent;
    this.startTokenIndex = oldStartTokenIndex;
    this.endTokenIndex = oldEndTokenIndex;
    return copy;
};
// If we didn't have any idea where in loc.tokens to look for tokens
// contained by this loc, a binary search would be appropriate, but
// because we maintain this.startTokenIndex and this.endTokenIndex as we
// traverse the AST, we only need to make small (linear) adjustments to
// those indexes with each recursive iteration.
TCp.findTokenRange = function (loc) {
    // In the unlikely event that loc.tokens[this.startTokenIndex] starts
    // *after* loc.start, we need to rewind this.startTokenIndex first.
    while (this.startTokenIndex > 0) {
        var token = loc.tokens[this.startTokenIndex];
        if (util.comparePos(loc.start, token.loc.start) < 0) {
            --this.startTokenIndex;
        }
        else
            break;
    }
    // In the unlikely event that loc.tokens[this.endTokenIndex - 1] ends
    // *before* loc.end, we need to fast-forward this.endTokenIndex first.
    while (this.endTokenIndex < loc.tokens.length) {
        var token = loc.tokens[this.endTokenIndex];
        if (util.comparePos(token.loc.end, loc.end) < 0) {
            ++this.endTokenIndex;
        }
        else
            break;
    }
    // Increment this.startTokenIndex until we've found the first token
    // contained by this node.
    while (this.startTokenIndex < this.endTokenIndex) {
        var token = loc.tokens[this.startTokenIndex];
        if (util.comparePos(token.loc.start, loc.start) < 0) {
            ++this.startTokenIndex;
        }
        else
            break;
    }
    // Index into loc.tokens of the first token within this node.
    loc.start.token = this.startTokenIndex;
    // Decrement this.endTokenIndex until we've found the first token after
    // this node (not contained by the node).
    while (this.endTokenIndex > this.startTokenIndex) {
        var token = loc.tokens[this.endTokenIndex - 1];
        if (util.comparePos(loc.end, token.loc.end) < 0) {
            --this.endTokenIndex;
        }
        else
            break;
    }
    // Index into loc.tokens of the first token *after* this node.
    // If loc.start.token === loc.end.token, the node contains no tokens,
    // and the index is that of the next token following this node.
    loc.end.token = this.endTokenIndex;
};