mod(es/parser): Program start at input start

[Austaras]

Description:

BREAKING CHANGE:

Related issue (if exists):
Closes #11167

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6c1a4e0

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[Copilot]

Pull Request Overview

This PR addresses an issue where the parser incorrectly positioned the program start, causing leading comments and JSDoc annotations to be misplaced after import statements in the generated output. The fix ensures that programs start at the actual beginning of the input, preserving the correct order of comments and code.

Key changes:

• Modified parser to correctly track program start position at input beginning
• Fixed comment positioning for files with leading comments before imports/code
• Updated test fixtures to reflect correct comment placement

Reviewed Changes

Copilot reviewed 293 out of 644 changed files in this pull request and generated no comments.

File	Description
Multiple test reference files (.1.normal.js)	Updated test outputs showing comments now correctly appear before imports instead of after
Test fixture output files	Fixed comment positioning in various scenarios including JSDoc, copyright notices, and inline comments
New test case files (crates/swc/tests/fixture/issues-110xx/11167/)	Added new test case demonstrating the fix for issue #11167

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Austaras]

Some investigation

For code

// 123
class A extends B {

}

Current swc would output

// 123
import { _ as _call_super } from "@swc/helpers/_/_call_super";
import { _ as _class_call_check } from "@swc/helpers/_/_class_call_check";
import { _ as _inherits } from "@swc/helpers/_/_inherits";
var A = /*#__PURE__*/ function(B1) {
    "use strict";
    _inherits(A, B1);
    function A() {
        _class_call_check(this, A);
        return _call_super(this, A, arguments);
    }
    return A;
}(B);

tsc would output

"use strict";
var __extends = (this && this.__extends) || (function () {
    var extendStatics = function (d, b) {
        extendStatics = Object.setPrototypeOf ||
            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
            function (d, b) { for (var p in b) if (Object.prototype.hasOwnProperty.call(b, p)) d[p] = b[p]; };
        return extendStatics(d, b);
    };
    return function (d, b) {
        if (typeof b !== "function" && b !== null)
            throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
        extendStatics(d, b);
        function __() { this.constructor = d; }
        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
    };
})();
// 123
var A = /** @class */ (function (_super) {
    __extends(A, _super);
    function A() {
        return _super !== null && _super.apply(this, arguments) || this;
    }
    return A;
}(B));

babel would output

function _callSuper(t, o, e) { return o = babelHelpers.getPrototypeOf(o), babelHelpers.possibleConstructorReturn(t, _isNativeReflectConstruct() ? Reflect.construct(o, e || [], babelHelpers.getPrototypeOf(t).constructor) : o.apply(t, e)); }
function _isNativeReflectConstruct() { try { var t = !Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); } catch (t) {} return (_isNativeReflectConstruct = function _isNativeReflectConstruct() { return !!t; })(); }
// 123
var A = /*#__PURE__*/function (_B) {
  function A() {
    babelHelpers.classCallCheck(this, A);
    return _callSuper(this, A, arguments);
  }
  babelHelpers.inherits(A, _B);
  return babelHelpers.createClass(A);
}(B);

This PR would change to babel output.

[Austaras]

Some comments would be lost because they're now attached to typescript syntax node which would be eliminated later.

[codspeed-hq]

CodSpeed Performance Report

Merging #11199 will not alter performance

_{Comparing Austaras:main (6c1a4e0) with main (dba23f5)}

Summary

✅ 138 untouched

[Copilot]

Pull Request Overview

Copilot reviewed 293 out of 4003 changed files in this pull request and generated no new comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull Request Overview

Copilot reviewed 293 out of 4007 changed files in this pull request and generated no new comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Copilot encountered an error and was unable to review this pull request. You can try again by re-requesting a review.

[github-actions]

Binary Sizes

File	Size
swc.linux-x64-gnu.node	31M (32023392 bytes)

Commit: 30f23ab

[kdy1]

CI failures look like a real failure, but I think it may be better to wait until I finish #11205