deno_lint 0.84.0

// Copyright 2020-2021 the Deno authors. All rights reserved. MIT license.
use super::Context;
use super::LintRule;
use crate::diagnostic::LintFix;
use crate::diagnostic::LintFixChange;
use crate::handler::Handler;
use crate::handler::Traverse;
use crate::tags;
use crate::tags::Tags;
use crate::Program;

use deno_ast::view as ast_view;
use deno_ast::SourceRange;
use deno_ast::SourceRanged;
use if_chain::if_chain;

#[derive(Debug)]
pub struct NoWindow;

const CODE: &str = "no-window";
const MESSAGE: &str = "Window is no longer available in Deno";
const HINT: &str = "Instead, use `globalThis`";
const FIX_DESC: &str = "Rename window to globalThis";

impl LintRule for NoWindow {
  fn tags(&self) -> Tags {
    &[tags::RECOMMENDED]
  }

  fn code(&self) -> &'static str {
    CODE
  }

  fn lint_program_with_ast_view(
    &self,
    context: &mut Context,
    program: Program<'_>,
  ) {
    NoWindowGlobalHandler.traverse(program, context);
  }
}

struct NoWindowGlobalHandler;

impl NoWindowGlobalHandler {
  fn add_diagnostic(&self, ctx: &mut Context, range: SourceRange) {
    ctx.add_diagnostic_with_fixes(
      range,
      CODE,
      MESSAGE,
      Some(HINT.to_string()),
      vec![LintFix {
        description: FIX_DESC.into(),
        changes: vec![LintFixChange {
          new_text: "globalThis".into(),
          range,
        }],
      }],
    );
  }
}

impl Handler for NoWindowGlobalHandler {
  fn member_expr(&mut self, expr: &ast_view::MemberExpr, ctx: &mut Context) {
    use deno_ast::view::Expr;
    if_chain! {
      if let Expr::Ident(ident) = &expr.obj;
      if ident.sym() == "window";
      if ctx.scope().is_global(&ident.inner.to_id());
      then {
        self.add_diagnostic(ctx, ident.range());
      }
    }
  }

  fn expr_stmt(&mut self, expr: &ast_view::ExprStmt, ctx: &mut Context) {
    use deno_ast::view::Expr;
    if_chain! {
      if let Expr::Ident(ident) = &expr.expr;
      if ident.sym() == "window";
      if ctx.scope().is_global(&ident.inner.to_id());
      then {
        self.add_diagnostic(ctx, ident.range());
      }
    }
  }
}

#[cfg(test)]
mod tests {
  use super::*;

  #[test]
  fn no_window_valid() {
    assert_lint_ok! {
      NoWindow,
      "fetch();",
      "self.fetch();",
      "globalThis.fetch();",

      // `window` is shadowed
      "const window = 42; window.fetch();",
      r#"const window = 42; window["fetch"]();"#,
      r#"const window = 42; window[`fetch`]();"#,
      "const window = 42; window.alert();",
      r#"const window = 42; window["alert"]();"#,
      r#"const window = 42; window[`alert`]();"#,

      // https://github.com/denoland/deno_lint/issues/1232
      "const params: { window: number } = { window: 23 };",
      "x.window"
    };
  }

  #[test]
  fn no_window_invalid() {
    assert_lint_err! {
      NoWindow,
      MESSAGE,
      HINT,
      r#"window.fetch()"#: [
        {
          col: 0,
          fix: (FIX_DESC, "globalThis.fetch()"),
        }
      ],
      r#"window["fetch"]()"#: [
        {
          col: 0,
          fix: (FIX_DESC, r#"globalThis["fetch"]()"#),
        }
      ],
      r#"window[`fetch`]()"#: [
        {
          col: 0,
          fix: (FIX_DESC, "globalThis[`fetch`]()"),
        }
      ],
      r#"
function foo() {
  const window = 42;
  return window;
}
window;"#: [
        {
          col: 0,
          line: 6,
          fix: (FIX_DESC, "
function foo() {
  const window = 42;
  return window;
}
globalThis;"),
        }
      ],
      r#"window.console.log()"#: [
        {
          col: 0,
          fix: (FIX_DESC, "globalThis.console.log()"),
        }
      ],
    };
  }
}