Split `MacArgs` in two.

`MacArgs` is an enum with three variants: `Empty`, `Delimited`, and `Eq`. It's
used in two ways:
- For representing attribute macro arguments (e.g. in `AttrItem`), where all
  three variants are used.
- For representing function-like macros (e.g. in `MacCall` and `MacroDef`),
  where only the `Delimited` variant is used.

In other words, `MacArgs` is used in two quite different places due to them
having partial overlap. I find this makes the code hard to read. It also leads
to various unreachable code paths, and allows invalid values (such as
accidentally using `MacArgs::Empty` in a `MacCall`).

This commit splits `MacArgs` in two:
- `DelimArgs` is a new struct just for the "delimited arguments" case. It is
  now used in `MacCall` and `MacroDef`.
- `AttrArgs` is a renaming of the old `MacArgs` enum for the attribute macro
  case. Its `Delimited` variant now contains a `DelimArgs`.

Various other related things are renamed as well.

These changes make the code clearer, avoids several unreachable paths, and
disallows the invalid values.

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs
index c2d0a662ddb..8c779579a4f 100644
--- a/compiler/rustc_lint/src/builtin.rs
+++ b/compiler/rustc_lint/src/builtin.rs
@@ -2030,10 +2030,10 @@ impl KeywordIdents {
 
 impl EarlyLintPass for KeywordIdents {
     fn check_mac_def(&mut self, cx: &EarlyContext<'_>, mac_def: &ast::MacroDef) {
-        self.check_tokens(cx, mac_def.body.inner_tokens());
+        self.check_tokens(cx, mac_def.body.tokens.clone());
     }
     fn check_mac(&mut self, cx: &EarlyContext<'_>, mac: &ast::MacCall) {
-        self.check_tokens(cx, mac.args.inner_tokens());
+        self.check_tokens(cx, mac.args.tokens.clone());
     }
     fn check_ident(&mut self, cx: &EarlyContext<'_>, ident: Ident) {
         self.check_ident_token(cx, UnderMacro(false), ident);