add ui test for failing doctest

Author: QuietMisdreavus

src/test/rustdoc-ui/failed-doctest-output.rs

@@ -0,0 +1,19 @@
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Issue #51162: A failed doctest was not printing its stdout/stderr
+
+// compile-flags:--test
+// disable-ui-testing-normalization
+
+/// ```
+/// panic!("oh no");
+/// ```
+pub struct SomeStruct;

src/test/rustdoc-ui/failed-doctest-output.stdout

@@ -0,0 +1,21 @@
+
+running 1 test
+test src/test/rustdoc-ui/failed-doctest-output.rs - SomeStruct (line 16) ... FAILED
+
+failures:
+
+---- src/test/rustdoc-ui/failed-doctest-output.rs - SomeStruct (line 16) stdout ----
+thread 'src/test/rustdoc-ui/failed-doctest-output.rs - SomeStruct (line 16)' panicked at 'test executable failed:
+
+thread 'main' panicked at 'oh no', src/test/rustdoc-ui/failed-doctest-output.rs:3:1
+note: Run with `RUST_BACKTRACE=1` for a backtrace.
+
+', librustdoc/test.rs:367:17
+note: Run with `RUST_BACKTRACE=1` for a backtrace.
+
+
+failures:
+    src/test/rustdoc-ui/failed-doctest-output.rs - SomeStruct (line 16)
+
+test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out
+