Add regression test for #139899

Author: GuillaumeGomez

tests/run-make/rustdoc-tempdir-removal/compile-error.rs

@@ -0,0 +1,5 @@
+#![doc(test(attr(deny(warnings))))]
+
+//! ```
+//! let a = 12;
+//! ```

tests/run-make/rustdoc-tempdir-removal/rmake.rs

@@ -0,0 +1,34 @@
+// This test ensures that no temporary folder is "left behind" when doctests fail for any reason.
+
+//@ only-linux
+
+use std::path::Path;
+
+use run_make_support::{path, rfs, rustdoc};
+
+fn run_doctest_and_check_tmpdir(tmp_dir: &Path, doctest: &str, edition: &str) {
+    let output =
+        rustdoc().input(doctest).env("TMPDIR", tmp_dir).arg("--test").edition(edition).run_fail();
+
+    output.assert_exit_code(101).assert_stdout_contains(
+        "test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out",
+    );
+
+    rfs::read_dir_entries(tmp_dir, |entry| {
+        panic!("Found an item inside the temporary folder: {entry:?}");
+    });
+}
+
+fn run_doctest_and_check_tmpdir_for_edition(tmp_dir: &Path, edition: &str) {
+    run_doctest_and_check_tmpdir(tmp_dir, "compile-error.rs", edition);
+    run_doctest_and_check_tmpdir(tmp_dir, "run-error.rs", edition);
+}
+
+fn main() {
+    let tmp_dir = path("tmp");
+    rfs::create_dir(&tmp_dir);
+
+    run_doctest_and_check_tmpdir_for_edition(&tmp_dir, "2018");
+    // We use the 2024 edition to check that it's also working for merged doctests.
+    run_doctest_and_check_tmpdir_for_edition(&tmp_dir, "2024");
+}

tests/run-make/rustdoc-tempdir-removal/run-error.rs

@@ -0,0 +1,3 @@
+//! ```
+//! panic!();
+//! ```