From cf312ae1f26e815dc1a898d634b001b8f315448e Mon Sep 17 00:00:00 2001
From: Steven Tang <yc@steventang.net>
Date: Wed, 7 Dec 2022 21:45:49 +1100
Subject: [PATCH] Add tests for #41731

Closes #41731
---
 .../issue-41731-infinite-macro-print.rs       | 15 ++++++++
 .../issue-41731-infinite-macro-print.stderr   | 38 +++++++++++++++++++
 .../issue-41731-infinite-macro-println.rs     | 15 ++++++++
 .../issue-41731-infinite-macro-println.stderr | 38 +++++++++++++++++++
 4 files changed, 106 insertions(+)
 create mode 100644 src/test/ui/infinite/issue-41731-infinite-macro-print.rs
 create mode 100644 src/test/ui/infinite/issue-41731-infinite-macro-print.stderr
 create mode 100644 src/test/ui/infinite/issue-41731-infinite-macro-println.rs
 create mode 100644 src/test/ui/infinite/issue-41731-infinite-macro-println.stderr

diff --git a/src/test/ui/infinite/issue-41731-infinite-macro-print.rs b/src/test/ui/infinite/issue-41731-infinite-macro-print.rs
new file mode 100644
index 00000000000..d52e6e7e9eb
--- /dev/null
+++ b/src/test/ui/infinite/issue-41731-infinite-macro-print.rs
@@ -0,0 +1,15 @@
+// compile-flags: -Z trace-macros
+
+#![recursion_limit = "5"]
+
+fn main() {
+    macro_rules! stack {
+        ($overflow:expr) => {
+            print!(stack!($overflow));
+            //~^ ERROR recursion limit reached while expanding
+            //~| ERROR format argument must be a string literal
+        };
+    }
+
+    stack!("overflow");
+}
diff --git a/src/test/ui/infinite/issue-41731-infinite-macro-print.stderr b/src/test/ui/infinite/issue-41731-infinite-macro-print.stderr
new file mode 100644
index 00000000000..e30b2039d69
--- /dev/null
+++ b/src/test/ui/infinite/issue-41731-infinite-macro-print.stderr
@@ -0,0 +1,38 @@
+error: recursion limit reached while expanding `$crate::format_args!`
+  --> $DIR/issue-41731-infinite-macro-print.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "10"]` attribute to your crate (`issue_41731_infinite_macro_print`)
+   = note: this error originates in the macro `print` which comes from the expansion of the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+note: trace_macro
+  --> $DIR/issue-41731-infinite-macro-print.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = note: expanding `stack! { "overflow" }`
+   = note: to `print! (stack! ("overflow")) ;`
+   = note: expanding `print! { stack! ("overflow") }`
+   = note: to `{ $crate :: io :: _print($crate :: format_args! (stack! ("overflow"))) ; }`
+   = note: expanding `stack! { "overflow" }`
+   = note: to `print! (stack! ("overflow")) ;`
+   = note: expanding `print! { stack! ("overflow") }`
+   = note: to `{ $crate :: io :: _print($crate :: format_args! (stack! ("overflow"))) ; }`
+
+error: format argument must be a string literal
+  --> $DIR/issue-41731-infinite-macro-print.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = note: this error originates in the macro `print` which comes from the expansion of the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: you might be missing a string literal to format with
+   |
+LL |             print!("{}", stack!($overflow));
+   |                    +++++
+
+error: aborting due to 2 previous errors
+
diff --git a/src/test/ui/infinite/issue-41731-infinite-macro-println.rs b/src/test/ui/infinite/issue-41731-infinite-macro-println.rs
new file mode 100644
index 00000000000..3c2b7ee023b
--- /dev/null
+++ b/src/test/ui/infinite/issue-41731-infinite-macro-println.rs
@@ -0,0 +1,15 @@
+// compile-flags: -Z trace-macros
+
+#![recursion_limit = "5"]
+
+fn main() {
+    macro_rules! stack {
+        ($overflow:expr) => {
+            println!(stack!($overflow));
+            //~^ ERROR recursion limit reached while expanding
+            //~| ERROR format argument must be a string literal
+        };
+    }
+
+    stack!("overflow");
+}
diff --git a/src/test/ui/infinite/issue-41731-infinite-macro-println.stderr b/src/test/ui/infinite/issue-41731-infinite-macro-println.stderr
new file mode 100644
index 00000000000..66b466dafa0
--- /dev/null
+++ b/src/test/ui/infinite/issue-41731-infinite-macro-println.stderr
@@ -0,0 +1,38 @@
+error: recursion limit reached while expanding `$crate::format_args_nl!`
+  --> $DIR/issue-41731-infinite-macro-println.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "10"]` attribute to your crate (`issue_41731_infinite_macro_println`)
+   = note: this error originates in the macro `println` which comes from the expansion of the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+note: trace_macro
+  --> $DIR/issue-41731-infinite-macro-println.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = note: expanding `stack! { "overflow" }`
+   = note: to `println! (stack! ("overflow")) ;`
+   = note: expanding `println! { stack! ("overflow") }`
+   = note: to `{ $crate :: io :: _print($crate :: format_args_nl! (stack! ("overflow"))) ; }`
+   = note: expanding `stack! { "overflow" }`
+   = note: to `println! (stack! ("overflow")) ;`
+   = note: expanding `println! { stack! ("overflow") }`
+   = note: to `{ $crate :: io :: _print($crate :: format_args_nl! (stack! ("overflow"))) ; }`
+
+error: format argument must be a string literal
+  --> $DIR/issue-41731-infinite-macro-println.rs:14:5
+   |
+LL |     stack!("overflow");
+   |     ^^^^^^^^^^^^^^^^^^
+   |
+   = note: this error originates in the macro `println` which comes from the expansion of the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)
+help: you might be missing a string literal to format with
+   |
+LL |             println!("{}", stack!($overflow));
+   |                      +++++
+
+error: aborting due to 2 previous errors
+