Account for version number in NtIdent hack

Issue #74616 tracks a backwards-compatibility hack for certain macros.
This has is implemented by hard-coding the filenames and macro names of
certain code that we want to continue to compile.

However, the initial implementation of the hack was based on the
directory structure when building the crate from its repository (e.g.
`js-sys/src/lib.rs`). When the crate is build as a dependency, it will
include a version number from the clone from the cargo registry (e.g.
`js-sys-0.3.17/src/lib.rs`), which would fail the check.

This commit modifies the backwards-compatibility hack to check that
desired crate name (`js-sys` or `time-macros-impl`) is a prefix of the
proper part of the path.

See https://github.com/rust-lang/rust/issues/76070#issuecomment-687215646
for more details.

5 files changed, 56 insertions, 10 deletions

diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs
index c6cc890b47f..a2c651d1537 100644
--- a/compiler/rustc_ast/src/token.rs
+++ b/compiler/rustc_ast/src/token.rs
@@ -809,9 +809,19 @@ impl Nonterminal {
             if let ExpnKind::Macro(_, macro_name) = orig_span.ctxt().outer_expn_data().kind {
                 let filename = source_map.span_to_filename(orig_span);
                 if let FileName::Real(RealFileName::Named(path)) = filename {
-                    if (path.ends_with("time-macros-impl/src/lib.rs")
-                        && macro_name == sym::impl_macros)
-                        || (path.ends_with("js-sys/src/lib.rs") && macro_name == sym::arrays)
+                    let matches_prefix = |prefix| {
+                        // Check for a path that ends with 'prefix*/src/lib.rs'
+                        let mut iter = path.components().rev();
+                        iter.next().and_then(|p| p.as_os_str().to_str()) == Some("lib.rs")
+                            && iter.next().and_then(|p| p.as_os_str().to_str()) == Some("src")
+                            && iter
+                                .next()
+                                .and_then(|p| p.as_os_str().to_str())
+                                .map_or(false, |p| p.starts_with(prefix))
+                    };
+
+                    if (macro_name == sym::impl_macros && matches_prefix("time-macros-impl"))
+                        || (macro_name == sym::arrays && matches_prefix("js-sys"))
                     {
                         let snippet = source_map.span_to_snippet(orig_span);
                         if snippet.as_deref() == Ok("$name") {
diff --git a/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.rs b/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.rs
index 35c101587de..bc82a2ff196 100644
--- a/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.rs
+++ b/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.rs
@@ -13,18 +13,37 @@ extern crate std;
 // place of a `None`-delimited group. This allows us to maintain
 // backwards compatibility for older versions of these crates.
 
-include!("js-sys/src/lib.rs");
-include!("time-macros-impl/src/lib.rs");
+mod no_version {
+    include!("js-sys/src/lib.rs");
+    include!("time-macros-impl/src/lib.rs");
 
-macro_rules! other {
-    ($name:ident) => {
-        #[my_macro] struct Three($name);
+    macro_rules! other {
+        ($name:ident) => {
+            #[my_macro] struct Three($name);
+        }
     }
+
+    struct Foo;
+    impl_macros!(Foo);
+    arrays!(Foo);
+    other!(Foo);
 }
 
-fn main() {
+mod with_version {
+    include!("js-sys-0.3.17/src/lib.rs");
+    include!("time-macros-impl-0.1.0/src/lib.rs");
+
+    macro_rules! other {
+        ($name:ident) => {
+            #[my_macro] struct Three($name);
+        }
+    }
+
     struct Foo;
     impl_macros!(Foo);
     arrays!(Foo);
     other!(Foo);
 }
+
+
+fn main() {}
diff --git a/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.stdout b/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.stdout
index d519daab1f2..e7645280a75 100644
--- a/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.stdout
+++ b/src/test/ui/proc-macro/group-compat-hack/group-compat-hack.stdout
@@ -1,3 +1,6 @@
 Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/time-macros-impl/src/lib.rs:5:21: 5:27 (#5) }, Ident { ident: "One", span: $DIR/time-macros-impl/src/lib.rs:5:28: 5:31 (#5) }, Group { delimiter: Parenthesis, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:27:18: 27:21 (#0) }], span: $DIR/time-macros-impl/src/lib.rs:5:31: 5:38 (#5) }, Punct { ch: ';', spacing: Alone, span: $DIR/time-macros-impl/src/lib.rs:5:38: 5:39 (#5) }]
 Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/js-sys/src/lib.rs:5:21: 5:27 (#9) }, Ident { ident: "Two", span: $DIR/js-sys/src/lib.rs:5:28: 5:31 (#9) }, Group { delimiter: Parenthesis, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:28:13: 28:16 (#0) }], span: $DIR/js-sys/src/lib.rs:5:31: 5:38 (#9) }, Punct { ch: ';', spacing: Alone, span: $DIR/js-sys/src/lib.rs:5:38: 5:39 (#9) }]
-Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/group-compat-hack.rs:21:21: 21:27 (#13) }, Ident { ident: "Three", span: $DIR/group-compat-hack.rs:21:28: 21:33 (#13) }, Group { delimiter: Parenthesis, stream: TokenStream [Group { delimiter: None, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:29:12: 29:15 (#0) }], span: $DIR/group-compat-hack.rs:21:34: 21:39 (#13) }], span: $DIR/group-compat-hack.rs:21:33: 21:40 (#13) }, Punct { ch: ';', spacing: Alone, span: $DIR/group-compat-hack.rs:21:40: 21:41 (#13) }]
+Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/group-compat-hack.rs:22:25: 22:31 (#13) }, Ident { ident: "Three", span: $DIR/group-compat-hack.rs:22:32: 22:37 (#13) }, Group { delimiter: Parenthesis, stream: TokenStream [Group { delimiter: None, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:29:12: 29:15 (#0) }], span: $DIR/group-compat-hack.rs:22:38: 22:43 (#13) }], span: $DIR/group-compat-hack.rs:22:37: 22:44 (#13) }, Punct { ch: ';', spacing: Alone, span: $DIR/group-compat-hack.rs:22:44: 22:45 (#13) }]
+Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/time-macros-impl-0.1.0/src/lib.rs:5:21: 5:27 (#19) }, Ident { ident: "One", span: $DIR/time-macros-impl-0.1.0/src/lib.rs:5:28: 5:31 (#19) }, Group { delimiter: Parenthesis, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:43:18: 43:21 (#0) }], span: $DIR/time-macros-impl-0.1.0/src/lib.rs:5:31: 5:38 (#19) }, Punct { ch: ';', spacing: Alone, span: $DIR/time-macros-impl-0.1.0/src/lib.rs:5:38: 5:39 (#19) }]
+Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/js-sys-0.3.17/src/lib.rs:5:21: 5:27 (#23) }, Ident { ident: "Two", span: $DIR/js-sys-0.3.17/src/lib.rs:5:28: 5:31 (#23) }, Group { delimiter: Parenthesis, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:44:13: 44:16 (#0) }], span: $DIR/js-sys-0.3.17/src/lib.rs:5:31: 5:38 (#23) }, Punct { ch: ';', spacing: Alone, span: $DIR/js-sys-0.3.17/src/lib.rs:5:38: 5:39 (#23) }]
+Called proc_macro_hack with TokenStream [Ident { ident: "struct", span: $DIR/group-compat-hack.rs:38:25: 38:31 (#27) }, Ident { ident: "Three", span: $DIR/group-compat-hack.rs:38:32: 38:37 (#27) }, Group { delimiter: Parenthesis, stream: TokenStream [Group { delimiter: None, stream: TokenStream [Ident { ident: "Foo", span: $DIR/group-compat-hack.rs:45:12: 45:15 (#0) }], span: $DIR/group-compat-hack.rs:38:38: 38:43 (#27) }], span: $DIR/group-compat-hack.rs:38:37: 38:44 (#27) }, Punct { ch: ';', spacing: Alone, span: $DIR/group-compat-hack.rs:38:44: 38:45 (#27) }]
diff --git a/src/test/ui/proc-macro/group-compat-hack/js-sys-0.3.17/src/lib.rs b/src/test/ui/proc-macro/group-compat-hack/js-sys-0.3.17/src/lib.rs
new file mode 100644
index 00000000000..d1a66940ebf
--- /dev/null
+++ b/src/test/ui/proc-macro/group-compat-hack/js-sys-0.3.17/src/lib.rs
@@ -0,0 +1,7 @@
+// ignore-test this is not a test
+
+macro_rules! arrays {
+    ($name:ident) => {
+        #[my_macro] struct Two($name);
+    }
+}
diff --git a/src/test/ui/proc-macro/group-compat-hack/time-macros-impl-0.1.0/src/lib.rs b/src/test/ui/proc-macro/group-compat-hack/time-macros-impl-0.1.0/src/lib.rs
new file mode 100644
index 00000000000..c94c3579209
--- /dev/null
+++ b/src/test/ui/proc-macro/group-compat-hack/time-macros-impl-0.1.0/src/lib.rs
@@ -0,0 +1,7 @@
+// ignore-test this is not a test
+
+macro_rules! impl_macros {
+    ($name:ident) => {
+        #[my_macro] struct One($name);
+    }
+}