From 0172d15fc1a0e68b03de2fcd44e91e5d88d1ea0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Wed, 15 Mar 2023 03:48:28 +0000
Subject: [PATCH] Fix #90557

---
 .../wrong_number_of_generic_args.rs           | 22 +++++++++++++++++--
 .../ui/lifetimes/missing-lifetime-in-alias.rs |  1 +
 tests/ui/macros/issue-90557.rs                | 18 +++++++++++++++
 tests/ui/macros/issue-90557.stderr            | 22 +++++++++++++++++++
 4 files changed, 61 insertions(+), 2 deletions(-)
 create mode 100644 tests/ui/macros/issue-90557.rs
 create mode 100644 tests/ui/macros/issue-90557.stderr

diff --git a/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs b/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs
index 821b8f75da5eb..359f3beeaa12b 100644
--- a/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs
+++ b/compiler/rustc_hir_analysis/src/structured_errors/wrong_number_of_generic_args.rs
@@ -594,7 +594,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
 
         match self.angle_brackets {
             AngleBrackets::Missing => {
-                let span = self.path_segment.ident.span;
+                let span = self.tcx.mark_span_for_resize(self.path_segment.ident.span);
 
                 // insert a suggestion of the form "Y<'a, 'b>"
                 let sugg = format!("<{}>", suggested_args);
@@ -618,6 +618,15 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
                     let last_lt = &self.gen_args.args[self.num_provided_lifetime_args() - 1];
                     (self.tcx.mark_span_for_resize(last_lt.span()).shrink_to_hi(), false)
                 };
+                let path_sp = self.path_segment.ident.span.peel_ctxt();
+                if !self.gen_args.args.iter().all(|arg| {
+                    arg.span().can_be_used_for_suggestions()
+                        && arg.span().peel_ctxt().ctxt() == path_sp.ctxt()
+                }) || !path_sp.can_be_used_for_suggestions()
+                {
+                    // Do not suggest syntax when macros are involved. (#90557)
+                    return;
+                }
                 let has_non_lt_args = self.num_provided_type_or_const_args() != 0;
                 let has_bindings = !self.gen_args.bindings.is_empty();
 
@@ -647,7 +656,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
 
         match self.angle_brackets {
             AngleBrackets::Missing | AngleBrackets::Implied => {
-                let span = self.path_segment.ident.span;
+                let span = self.tcx.mark_span_for_resize(self.path_segment.ident.span);
 
                 // insert a suggestion of the form "Y<T, U>"
                 let sugg = format!("<{}>", suggested_args);
@@ -661,6 +670,15 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
                 );
             }
             AngleBrackets::Available => {
+                let path_sp = self.path_segment.ident.span.peel_ctxt();
+                if !self.gen_args.args.iter().all(|arg| {
+                    arg.span().can_be_used_for_suggestions()
+                        && arg.span().peel_ctxt().ctxt() == path_sp.ctxt()
+                }) || !path_sp.can_be_used_for_suggestions()
+                {
+                    // Do not suggest syntax when macros are involved. (#90557)
+                    return;
+                }
                 let gen_args_span = self.tcx.mark_span_for_resize(self.gen_args.span().unwrap());
                 let sugg_offset =
                     self.get_lifetime_args_offset() + self.num_provided_type_or_const_args();
diff --git a/tests/ui/lifetimes/missing-lifetime-in-alias.rs b/tests/ui/lifetimes/missing-lifetime-in-alias.rs
index 51c564c011a86..44be06e1fef7c 100644
--- a/tests/ui/lifetimes/missing-lifetime-in-alias.rs
+++ b/tests/ui/lifetimes/missing-lifetime-in-alias.rs
@@ -27,5 +27,6 @@ type C<'a, 'b> = <A<'a> as Trait>::Bar;
 //~| NOTE expected named lifetime parameter
 //~| NOTE these named lifetimes are available to use
 //~| NOTE expected 1 lifetime argument
+//~| NOTE in this expansion of desugaring of a resized `Span`
 
 fn main() {}
diff --git a/tests/ui/macros/issue-90557.rs b/tests/ui/macros/issue-90557.rs
new file mode 100644
index 0000000000000..5a9aa5dabb70c
--- /dev/null
+++ b/tests/ui/macros/issue-90557.rs
@@ -0,0 +1,18 @@
+struct Example<T, U> {
+    foo: T,
+    bar: U,
+}
+
+macro_rules! impl_example {
+    ($($t:ty)+) => {$(
+        impl Example<$t> { //~ ERROR struct takes 2 generic arguments but 1 generic argument was supplied
+            fn baz() {
+                println!(":)");
+            }
+        }
+    )+}
+}
+
+impl_example! { u8 }
+
+fn main() {}
diff --git a/tests/ui/macros/issue-90557.stderr b/tests/ui/macros/issue-90557.stderr
new file mode 100644
index 0000000000000..f28521efe75c1
--- /dev/null
+++ b/tests/ui/macros/issue-90557.stderr
@@ -0,0 +1,22 @@
+error[E0107]: struct takes 2 generic arguments but 1 generic argument was supplied
+  --> $DIR/issue-90557.rs:8:14
+   |
+LL |         impl Example<$t> {
+   |              ^^^^^^^ expected 2 generic arguments
+...
+LL | impl_example! { u8 }
+   | --------------------
+   | |               |
+   | |               supplied 1 generic argument
+   | in this macro invocation
+   |
+note: struct defined here, with 2 generic parameters: `T`, `U`
+  --> $DIR/issue-90557.rs:1:8
+   |
+LL | struct Example<T, U> {
+   |        ^^^^^^^ -  -
+   = note: this error originates in the macro `impl_example` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0107`.