rustdoc: Write newline differently

Fix the panic in write_message() which expects messages to contain
no embedded newlines. We still want a trailing newline at the end
of the file though, so write it in different manner.

Doctest runner no longer panics, but the output is kinda broken
when `compile_fail` doctests are present. This is because they
are not mergeable.

Author: ilammy

library/test/src/formatters/junit.rs

@@ -189,8 +189,10 @@ impl<T: Write> OutputFormatter for JunitFormatter<T> {
         compilation_time: f64,
     ) -> io::Result<()> {
         self.write_message(&format!(
-            "<report total_time=\"{total_time}\" compilation_time=\"{compilation_time}\"></report>\n",
-        ))
+            "<report total_time=\"{total_time}\" compilation_time=\"{compilation_time}\"></report>",
+        ))?;
+        self.out.write_all(b"\n")?;
+        Ok(())
     }
 }
 

tests/run-make/doctests-junit/doctest-2024.xml

@@ -0,0 +1,3 @@
+<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="0" tests="2" skipped="0" ><testcase classname="doctest.rs" name="add (line 1)" time="$TIME"/><testcase classname="doctest.rs" name="add (line 5)" time="$TIME"/><system-out/><system-err/></testsuite></testsuites>
+<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="0" tests="1" skipped="0" ><testcase classname="doctest.rs" name="add (line 9)" time="$TIME"/><system-out/><system-err/></testsuite></testsuites>
+<report total_time="$TIME" compilation_time="$TIME"></report>

tests/run-make/doctests-junit/rmake.rs

@@ -12,7 +12,7 @@ fn main() {
     rustc().input("doctest.rs").crate_type("rlib").output(&rlib).run();
 
     run_doctests(&rlib, "2021", "doctest-2021.xml");
-    run_doctests_fail(&rlib, "2024");
+    run_doctests(&rlib, "2024", "doctest-2024.xml");
 }
 
 #[track_caller]
@@ -31,42 +31,14 @@ fn run_doctests(rlib: &Path, edition: &str, expected_xml: &str) {
         .run();
     let rustdoc_stdout = &rustdoc_out.stdout_utf8();
 
-    python_command().arg("validate_junit.py").stdin_buf(rustdoc_stdout).run();
+    // FIXME: merged output of compile_fail tests is broken
+    if edition != "2024" {
+        python_command().arg("validate_junit.py").stdin_buf(rustdoc_stdout).run();
+    }
 
     diff()
         .expected_file(expected_xml)
         .actual_text("output", rustdoc_stdout)
-        .normalize(r#"\btime="[0-9.]+""#, r#"time="$$TIME""#)
-        .run();
-}
-
-// FIXME: gone in the next patch
-#[track_caller]
-fn run_doctests_fail(rlib: &Path, edition: &str) {
-    let rustdoc_out = rustdoc()
-        .input("doctest.rs")
-        .args(&[
-            "--test",
-            "--test-args=-Zunstable-options",
-            "--test-args=--test-threads=1",
-            "--test-args=--format=junit",
-        ])
-        .edition(edition)
-        .env("RUST_BACKTRACE", "0")
-        .extern_("doctest", rlib.display().to_string())
-        .run_fail();
-    let rustdoc_stderr = &rustdoc_out.stderr_utf8();
-
-    diff()
-        .expected_text(
-            "expected",
-            r#"
-thread 'main' ($TID) panicked at library/test/src/formatters/junit.rs:22:9:
-assertion failed: !s.contains('\n')
-note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
-"#,
-        )
-        .actual_text("actual", rustdoc_stderr)
-        .normalize(r#"thread 'main' \([0-9]+\)"#, r#"thread 'main' ($$TID)"#)
+        .normalize(r#"\b(time|total_time|compilation_time)="[0-9.]+""#, r#"$1="$$TIME""#)
         .run();
 }