Auto merge of #54111 - nikomatsakis:issue-53686-keywords-and-macros, r=alexcrichton

warn about keywords in macro invocations

Fixes #53686

r? @alexcrichton

Author: bors

src/librustc/lint/context.rs

@@ -1117,6 +1117,13 @@ impl<'a> ast_visit::Visitor<'a> for EarlyContext<'a> {
     }
 
     fn visit_mac(&mut self, mac: &'a ast::Mac) {
+        // FIXME(#54110): So, this setup isn't really right. I think
+        // that (a) the libsyntax visitor ought to be doing this as
+        // part of `walk_mac`, and (b) we should be calling
+        // `visit_path`, *but* that would require a `NodeId`, and I
+        // want to get #53686 fixed quickly. -nmatsakis
+        ast_visit::walk_path(self, &mac.node.path);
+
         run_lints!(self, check_mac, mac);
     }
 }

src/librustc_lint/lib.rs

@@ -90,7 +90,7 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
     macro_rules! add_pre_expansion_builtin {
         ($sess:ident, $($name:ident),*,) => (
             {$(
-                store.register_early_pass($sess, false, box $name);
+                store.register_pre_expansion_pass($sess, box $name);
                 )*}
             )
     }

src/test/ui/rust-2018/async-ident.fixed

@@ -26,7 +26,9 @@ macro_rules! foo {
     //~| WARN hard error in the 2018 edition
 }
 
-foo!(async);
+foo!(r#async);
+    //~^ ERROR async
+    //~| WARN hard error in the 2018 edition
 
 mod dont_lint_raw {
     fn r#async() {}

src/test/ui/rust-2018/async-ident.rs

@@ -27,6 +27,8 @@ macro_rules! foo {
 }
 
 foo!(async);
+    //~^ ERROR async
+    //~| WARN hard error in the 2018 edition
 
 mod dont_lint_raw {
     fn r#async() {}

src/test/ui/rust-2018/async-ident.stderr

@@ -31,7 +31,16 @@ LL |     ($async:expr, async) => {};
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:36:11
+  --> $DIR/async-ident.rs:29:6
+   |
+LL | foo!(async);
+   |      ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
+   = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
+
+error: `async` is a keyword in the 2018 edition
+  --> $DIR/async-ident.rs:38:11
    |
 LL |     trait async {}
    |           ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -40,7 +49,7 @@ LL |     trait async {}
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:40:10
+  --> $DIR/async-ident.rs:42:10
    |
 LL |     impl async for MyStruct {}
    |          ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -49,7 +58,7 @@ LL |     impl async for MyStruct {}
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:46:12
+  --> $DIR/async-ident.rs:48:12
    |
 LL |     static async: u32 = 0;
    |            ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -58,7 +67,7 @@ LL |     static async: u32 = 0;
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:52:11
+  --> $DIR/async-ident.rs:54:11
    |
 LL |     const async: u32 = 0;
    |           ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -67,7 +76,7 @@ LL |     const async: u32 = 0;
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:58:15
+  --> $DIR/async-ident.rs:60:15
    |
 LL | impl Foo { fn async() {} }
    |               ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -76,7 +85,7 @@ LL | impl Foo { fn async() {} }
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:63:12
+  --> $DIR/async-ident.rs:65:12
    |
 LL |     struct async {}
    |            ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -85,7 +94,7 @@ LL |     struct async {}
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:66:9
+  --> $DIR/async-ident.rs:68:9
    |
 LL |     let async: async = async {};
    |         ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -94,7 +103,7 @@ LL |     let async: async = async {};
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:66:16
+  --> $DIR/async-ident.rs:68:16
    |
 LL |     let async: async = async {};
    |                ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -103,7 +112,7 @@ LL |     let async: async = async {};
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:66:24
+  --> $DIR/async-ident.rs:68:24
    |
 LL |     let async: async = async {};
    |                        ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -112,7 +121,7 @@ LL |     let async: async = async {};
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:77:19
+  --> $DIR/async-ident.rs:79:19
    |
 LL |     () => (pub fn async() {})
    |                   ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
@@ -121,13 +130,13 @@ LL |     () => (pub fn async() {})
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
 error: `async` is a keyword in the 2018 edition
-  --> $DIR/async-ident.rs:84:6
+  --> $DIR/async-ident.rs:86:6
    |
 LL |     (async) => (1)
    |      ^^^^^ help: you can use a raw identifier to stay compatible: `r#async`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
    = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
 
-error: aborting due to 14 previous errors
+error: aborting due to 15 previous errors
 

src/test/ui/rust-2018/try-macro.fixed

@@ -0,0 +1,16 @@
+// Test that `try!` macros are rewritten.
+
+// run-rustfix
+// compile-pass
+
+#![warn(rust_2018_compatibility)]
+#![allow(unused_variables)]
+#![allow(dead_code)]
+
+fn foo() -> Result<usize, ()> {
+    let x: Result<usize, ()> = Ok(22);
+    r#try!(x);
+    Ok(44)
+}
+
+fn main() { }

src/test/ui/rust-2018/try-macro.rs

@@ -0,0 +1,16 @@
+// Test that `try!` macros are rewritten.
+
+// run-rustfix
+// compile-pass
+
+#![warn(rust_2018_compatibility)]
+#![allow(unused_variables)]
+#![allow(dead_code)]
+
+fn foo() -> Result<usize, ()> {
+    let x: Result<usize, ()> = Ok(22);
+    try!(x);
+    Ok(44)
+}
+
+fn main() { }

src/test/ui/rust-2018/try-macro.stderr

@@ -0,0 +1,15 @@
+warning: `try` is a keyword in the 2018 edition
+  --> $DIR/try-macro.rs:12:5
+   |
+LL |     try!(x);
+   |     ^^^ help: you can use a raw identifier to stay compatible: `r#try`
+   |
+note: lint level defined here
+  --> $DIR/try-macro.rs:6:9
+   |
+LL | #![warn(rust_2018_compatibility)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^
+   = note: #[warn(keyword_idents)] implied by #[warn(rust_2018_compatibility)]
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
+   = note: for more information, see issue #49716 <https://github.com/rust-lang/rust/issues/49716>
+