src/librustc_expand/mut_visit/tests.rs

   1 use crate::tests::{matches_codepattern, string_to_crate};
   2
   3 use rustc_ast::ast::{self, Ident};
   4 use rustc_ast::mut_visit::{self, MutVisitor};
   5 use rustc_ast::with_default_globals;
   6 use rustc_ast_pretty::pprust;
   7
   8 // This version doesn't care about getting comments or doc-strings in.
   9 fn fake_print_crate(s: &mut pprust::State<'_>, krate: &ast::Crate) {
  10     s.print_mod(&krate.module, &krate.attrs)
  11 }
  12
  13 // Change every identifier to "zz".
  14 struct ToZzIdentMutVisitor;
  15
  16 impl MutVisitor for ToZzIdentMutVisitor {
  17     fn visit_ident(&mut self, ident: &mut ast::Ident) {
  18         *ident = Ident::from_str("zz");
  19     }
  20     fn visit_mac(&mut self, mac: &mut ast::MacCall) {
  21         mut_visit::noop_visit_mac(mac, self)
  22     }
  23 }
  24
  25 // Maybe add to `expand.rs`.
  26 macro_rules! assert_pred {
  27     ($pred:expr, $predname:expr, $a:expr , $b:expr) => {{
  28         let pred_val = $pred;
  29         let a_val = $a;
  30         let b_val = $b;
  31         if !(pred_val(&a_val, &b_val)) {
  32             panic!("expected args satisfying {}, got {} and {}", $predname, a_val, b_val);
  33         }
  34     }};
  35 }
  36
  37 // Make sure idents get transformed everywhere.
  38 #[test]
  39 fn ident_transformation() {
  40     with_default_globals(|| {
  41         let mut zz_visitor = ToZzIdentMutVisitor;
  42         let mut krate =
  43             string_to_crate("#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}".to_string());
  44         zz_visitor.visit_crate(&mut krate);
  45         assert_pred!(
  46             matches_codepattern,
  47             "matches_codepattern",
  48             pprust::to_string(|s| fake_print_crate(s, &krate)),
  49             "#[zz]mod zz{fn zz(zz:zz,zz:zz){zz!(zz,zz,zz);zz;zz}}".to_string()
  50         );
  51     })
  52 }
  53
  54 // Make sure idents get transformed even inside macro defs.
  55 #[test]
  56 fn ident_transformation_in_defs() {
  57     with_default_globals(|| {
  58         let mut zz_visitor = ToZzIdentMutVisitor;
  59         let mut krate = string_to_crate(
  60             "macro_rules! a {(b $c:expr $(d $e:token)f+ => \
  61             (g $(d $d $e)+))} "
  62                 .to_string(),
  63         );
  64         zz_visitor.visit_crate(&mut krate);
  65         assert_pred!(
  66             matches_codepattern,
  67             "matches_codepattern",
  68             pprust::to_string(|s| fake_print_crate(s, &krate)),
  69             "macro_rules! zz{(zz$zz:zz$(zz $zz:zz)zz+=>(zz$(zz$zz$zz)+))}".to_string()
  70         );
  71     })
  72 }