message: Don't inline process.env.x if x is not registered as global.
  Fix
diff: @@ -33,28 +33,39 @@ impl Fold<Expr> for InlineGlobals {
  obj:
  ExprOrSuper::Expr(box Expr::Ident(Ident {
  sym: js_word!("process"),
  + span: process_span,
  ..
  })),
  prop:
  box Expr::Ident(Ident {
  sym: js_word!("env"),
  + span: env_span,
  ..
  }),
  - span: _,
  - computed: _,
  + span: obj_span,
  + computed: obj_computed,
  })),
  prop,
  - computed: _,
  + computed,
  }) => match *prop {
  Expr::Ident(Ident { ref sym, .. }) => {
  if let Some(env) = self.envs.get(sym) {
  return env.clone();
  }
  - return Expr::Lit(Lit::Str(Str {
  - value: js_word!(""),
  + return Expr::Member(MemberExpr {
  span,
  - has_escape: false,
  - }));
  + obj: ExprOrSuper::Expr(box Expr::Member(MemberExpr {
  + obj: ExprOrSuper::Expr(box Expr::Ident(Ident::new(
  + js_word!("process"),
  + process_span,
  + ))),
  + prop: box Expr::Ident(Ident::new(js_word!("env"), env_span)),
  + span: obj_span,
  + computed: obj_computed,
  + })),
  + prop,
  + computed,
  + });
  }
  _ => unimplemented!("node.env.NONE-IDENT"),
  },
  @@ -112,6 +123,17 @@ mod tests {
  mk_map(tester, values, false)
  }
  + test!(
  + ::swc_ecma_parser::Syntax::default(),
  + |tester| InlineGlobals {
  + envs: envs(tester, &[]),
  + globals: globals(tester, &[]),
  + },
  + issue_215,
  + r#"if (process.env.x === 'development') {}"#,
  + r#"if (process.env.x === 'development') {}"#
  + );
  +
  test!(
  ::swc_ecma_parser::Syntax::default(),
  |tester| InlineGlobals {
  