oxc-project/oxc · error · OxcDiagnostic

Prefer `globalThis` over environment-specific global aliases

Error message

Prefer `globalThis` over environment-specific global aliases like `window`, `self`, and `global`.

What it means

Diagnostic from the unicorn/prefer-global-this lint rule. It fires when code references an environment-specific global alias (`window`, `self`, `global`, or `globalThis` variants under unary checks) instead of the standard `globalThis`, making the code non-portable across browsers, workers, and Node. The flagged input is the identifier reference to the alias. It is a lint suggestion, not a runtime error.

Source

Thrown at crates/oxc_linter/src/rules/unicorn/prefer_global_this.rs:10

use oxc_ast::{AstKind, ast::Expression};
use oxc_diagnostics::OxcDiagnostic;
use oxc_macros::declare_oxc_lint;
use oxc_span::{GetSpan, Span};
use oxc_syntax::operator::UnaryOperator;

use crate::{AstNode, context::LintContext, rule::Rule};

fn prefer_global_this_diagnostic(span: Span) -> OxcDiagnostic {
    OxcDiagnostic::warn("Prefer `globalThis` over environment-specific global aliases like `window`, `self`, and `global`.")
        .with_help("Replace the alias with `globalThis`.")
        .with_note("https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis")
        .with_label(span)
}

#[derive(Debug, Default, Clone)]
pub struct PreferGlobalThis;

declare_oxc_lint!(
    /// ### What it does
    ///
    /// Enforces the use of [`globalThis`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis) instead of
    /// environment‑specific global object aliases (`window`, `self`, or `global`).
    ///
    /// Using the standard `globalThis` makes your code portable across browsers, Web Workers, Node.js,
    /// and future JavaScript runtimes.
    ///
    /// ### Why is this bad?

View on GitHub (pinned to e1e7af627c)

Solutions

1. Replace `window`/`self`/`global` with `globalThis`
2. Use `typeof globalThis` checks instead of alias-specific environment detection
3. Apply the rule's auto-fix

When it happens

Trigger: Thrown at crates/oxc_linter/src/rules/unicorn/prefer_global_this.rs:10 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of oxc-project/oxc@e1e7af627c (2026-08-20). Data as JSON: /api/errors/29739dd7c106b19b. Report an issue: GitHub.