WIP: snapshot test for #72550

src/test/run-make-fulldeps/issue-72550/Makefile

@@ -0,0 +1,33 @@
+-include ../tools.mk
+
+
+ifeq ($(UNAME),Darwin)
+SNAPSHOT_NAME := apple.stderr
+else
+ifdef IS_WINDOWS
+# TODO: Actually get the line numbers for windows and linux
+# TODO: Find a way to prevent the snapshot from changing every time the
+#       implementation files chage. Probably using `sed` or `cat-and-grep`?
+SNAPSHOT_NAME := windows.stderr
+else
+# TODO: which other platforms use this branch?
+SNAPSHOT_NAME := linux.stderr
+endif
+endif
+
+ifdef BLESS
+COMPARE_SNAPSHOTS := echo "updating snapshot $(SNAPSHOT_NAME)" && mv $(TMPDIR)/panic.stderr.actual $(SNAPSHOT_NAME)
+else
+COMPARE_SNAPSHOTS := diff -u $(SNAPSHOT_NAME) $(TMPDIR)/panic.stderr.actual \
+	|| ( \
+		echo "stderr does not match snapshot $(SNAPSHOT_NAME)." && \
+		echo "Re-run with BLESS=1 to update." && \
+		exit 1 \
+	)
+endif
+
+
+all:
+	$(RUSTC) -C debuginfo=2 test.rs
+	RUST_BACKTRACE=1 $(call RUN,test) 2> $(TMPDIR)/panic.stderr.actual && exit 1 || exit 0
+	$(COMPARE_SNAPSHOTS)

src/test/run-make-fulldeps/issue-72550/apple.stderr

@@ -0,0 +1,44 @@
+thread 'main' panicked at 'explicit panic', test.rs:2:5
+stack backtrace:
+   0: backtrace::backtrace::libunwind::trace
+             at /Users/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86
+   1: backtrace::backtrace::trace_unsynchronized
+             at /Users/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66
+   2: std::sys_common::backtrace::_print_fmt
+             at src/libstd/sys_common/backtrace.rs:78
+   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
+             at src/libstd/sys_common/backtrace.rs:59
+   4: core::fmt::write
+             at src/libcore/fmt/mod.rs:1069
+   5: std::io::Write::write_fmt
+             at src/libstd/io/mod.rs:1439
+   6: std::sys_common::backtrace::_print
+             at src/libstd/sys_common/backtrace.rs:62
+   7: std::sys_common::backtrace::print
+             at src/libstd/sys_common/backtrace.rs:49
+   8: std::panicking::default_hook::{{closure}}
+             at src/libstd/panicking.rs:198
+   9: std::panicking::default_hook
+             at src/libstd/panicking.rs:218
+  10: std::panicking::rust_panic_with_hook
+             at src/libstd/panicking.rs:511
+  11: std::panicking::begin_panic
+             at src/libcore/unicode/unicode_data.rs:82
+  12: test::main
+             at ./test.rs:2
+  13: std::rt::lang_start::{{closure}}
+             at /Users/alsuren/.rustup/toolchains/nightly-x86_64-apple-darwin/lib/rustlib/src/rust/src/libstd/rt.rs:67
+  14: std::rt::lang_start_internal::{{closure}}
+             at src/libstd/rt.rs:52
+  15: std::panicking::try::do_call
+             at src/libstd/panicking.rs:331
+  16: std::panicking::try
+             at src/libstd/panicking.rs:274
+  17: std::panic::catch_unwind
+             at src/libstd/panic.rs:394
+  18: std::rt::lang_start_internal
+             at src/libstd/rt.rs:51
+  19: std::rt::lang_start
+             at /Users/alsuren/.rustup/toolchains/nightly-x86_64-apple-darwin/lib/rustlib/src/rust/src/libstd/rt.rs:67
+  20: main
+note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

src/test/run-make-fulldeps/issue-72550/linux.stderr

@@ -0,0 +1,21 @@
+thread 'main' panicked at 'explicit panic', test.rs:2:5
+stack backtrace:
+   0: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
+   1: core::fmt::write
+   2: std::io::Write::write_fmt
+   3: std::panicking::default_hook::{{closure}}
+   4: std::panicking::default_hook
+   5: std::panicking::rust_panic_with_hook
+   6: std::panicking::begin_panic
+             at /checkout/src/libstd/panicking.rs:410
+   7: test::main
+             at ./test.rs:2
+   8: std::rt::lang_start::{{closure}}
+             at /checkout/src/libstd/rt.rs:67
+   9: std::rt::lang_start_internal
+  10: std::rt::lang_start
+             at /checkout/src/libstd/rt.rs:67
+  11: main
+  12: __libc_start_main
+  13: _start
+note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

src/test/run-make-fulldeps/issue-72550/test.rs

@@ -0,0 +1,3 @@
+fn main() {
+    panic!();
+}

src/test/run-make-fulldeps/issue-72550/windows.stderr

@@ -0,0 +1,15 @@
+thread 'main' panicked at 'explicit panic', test.rs:2:5
+stack backtrace:
+   0: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
+   1: core::fmt::write
+   2: std::io::Write::write_fmt
+   3: std::panicking::default_hook::{{closure}}
+   4: std::panicking::default_hook
+   5: std::panicking::rust_panic_with_hook
+   6: std::panicking::begin_panic
+   7: test::main
+   8: std::rt::lang_start::{{closure}}
+   9: std::rt::lang_start_internal
+  10: std::rt::lang_start
+  11: main
+note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.