Implement compiletest `--new-output-capture`, in stable Rust
diff --git a/src/tools/compiletest/src/common.rs b/src/tools/compiletest/src/common.rs
index 89b1b4f..62fdee9 100644
--- a/src/tools/compiletest/src/common.rs
+++ b/src/tools/compiletest/src/common.rs
@@ -667,6 +667,10 @@ pub struct Config {
/// to avoid `!nocapture` double-negatives.
pub nocapture: bool,
+ /// True if the experimental new output-capture implementation should be
+ /// used, avoiding the need for `#![feature(internal_output_capture)]`.
+ pub new_output_capture: bool,
+
/// Needed both to construct [`build_helper::git::GitConfig`].
pub nightly_branch: String,
pub git_merge_commit_email: String,
@@ -784,6 +788,7 @@ pub fn incomplete_for_rustdoc_gui_test() -> Config {
builtin_cfg_names: Default::default(),
supported_crate_types: Default::default(),
nocapture: Default::default(),
+ new_output_capture: Default::default(),
nightly_branch: Default::default(),
git_merge_commit_email: Default::default(),
profiler_runtime: Default::default(),
diff --git a/src/tools/compiletest/src/executor.rs b/src/tools/compiletest/src/executor.rs
index 818d171..b0dc247 100644
--- a/src/tools/compiletest/src/executor.rs
+++ b/src/tools/compiletest/src/executor.rs
@@ -168,12 +168,17 @@ enum CaptureKind {
/// Use the old output-capture implementation, which relies on the unstable
/// library feature `#![feature(internal_output_capture)]`.
Old { buf: Arc<Mutex<Vec<u8>>> },
+
+ /// Use the new output-capture implementation, which only uses stable Rust.
+ New { buf: output_capture::CaptureBuf },
}
impl CaptureKind {
fn for_config(config: &Config) -> Self {
if config.nocapture {
Self::None
+ } else if config.new_output_capture {
+ Self::New { buf: output_capture::CaptureBuf::new() }
} else {
// Create a capure buffer for `io::set_output_capture`.
Self::Old { buf: Default::default() }
@@ -184,21 +189,30 @@ fn should_set_panic_hook(&self) -> bool {
match self {
Self::None => false,
Self::Old { .. } => true,
+ Self::New { .. } => true,
}
}
fn stdout(&self) -> &dyn ConsoleOut {
- &output_capture::Stdout
+ self.capture_buf_or(&output_capture::Stdout)
}
fn stderr(&self) -> &dyn ConsoleOut {
- &output_capture::Stderr
+ self.capture_buf_or(&output_capture::Stderr)
+ }
+
+ fn capture_buf_or<'a>(&'a self, fallback: &'a dyn ConsoleOut) -> &'a dyn ConsoleOut {
+ match self {
+ Self::None | Self::Old { .. } => fallback,
+ Self::New { buf } => buf,
+ }
}
fn into_inner(self) -> Option<Vec<u8>> {
match self {
Self::None => None,
Self::Old { buf } => Some(buf.lock().unwrap_or_else(|e| e.into_inner()).to_vec()),
+ Self::New { buf } => Some(buf.into_inner().into()),
}
}
}
diff --git a/src/tools/compiletest/src/lib.rs b/src/tools/compiletest/src/lib.rs
index 875d497..f647f96 100644
--- a/src/tools/compiletest/src/lib.rs
+++ b/src/tools/compiletest/src/lib.rs
@@ -178,6 +178,12 @@ pub fn parse_config(args: Vec<String>) -> Config {
// FIXME: Temporarily retained so we can point users to `--no-capture`
.optflag("", "nocapture", "")
.optflag("", "no-capture", "don't capture stdout/stderr of tests")
+ .optopt(
+ "N",
+ "new-output-capture",
+ "enables or disables the new output-capture implementation",
+ "off|on",
+ )
.optflag("", "profiler-runtime", "is the profiler runtime enabled for this target")
.optflag("h", "help", "show this message")
.reqopt("", "channel", "current Rust channel", "CHANNEL")
@@ -462,6 +468,14 @@ fn opt_path(m: &getopts::Matches, nm: &str) -> Utf8PathBuf {
supported_crate_types: OnceLock::new(),
nocapture: matches.opt_present("no-capture"),
+ new_output_capture: {
+ let value = matches
+ .opt_str("new-output-capture")
+ .or_else(|| env::var("COMPILETEST_NEW_OUTPUT_CAPTURE").ok())
+ .unwrap_or_else(|| "off".to_owned());
+ parse_bool_option(&value)
+ .unwrap_or_else(|| panic!("unknown `--new-output-capture` value `{value}` given"))
+ },
nightly_branch: matches.opt_str("nightly-branch").unwrap(),
git_merge_commit_email: matches.opt_str("git-merge-commit-email").unwrap(),
@@ -477,6 +491,19 @@ fn opt_path(m: &getopts::Matches, nm: &str) -> Utf8PathBuf {
}
}
+/// Parses the same set of boolean values accepted by rustc command-line arguments.
+///
+/// Accepting all of these values is more complicated than just picking one
+/// pair, but has the advantage that contributors who are used to rustc
+/// shouldn't have to think about which values are legal.
+fn parse_bool_option(value: &str) -> Option<bool> {
+ match value {
+ "off" | "no" | "n" | "false" => Some(false),
+ "on" | "yes" | "y" | "true" => Some(true),
+ _ => None,
+ }
+}
+
pub fn opt_str(maybestr: &Option<String>) -> &str {
match *maybestr {
None => "(none)",
diff --git a/src/tools/compiletest/src/output_capture.rs b/src/tools/compiletest/src/output_capture.rs
index e5e3e14..de1aea1 100644
--- a/src/tools/compiletest/src/output_capture.rs
+++ b/src/tools/compiletest/src/output_capture.rs
@@ -1,5 +1,6 @@
use std::fmt;
use std::panic::RefUnwindSafe;
+use std::sync::Mutex;
pub trait ConsoleOut: fmt::Debug + RefUnwindSafe {
fn write_fmt(&self, args: fmt::Arguments<'_>);
@@ -22,3 +23,30 @@ fn write_fmt(&self, args: fmt::Arguments<'_>) {
eprint!("{args}");
}
}
+
+pub(crate) struct CaptureBuf {
+ inner: Mutex<String>,
+}
+
+impl CaptureBuf {
+ pub(crate) fn new() -> Self {
+ Self { inner: Mutex::new(String::new()) }
+ }
+
+ pub(crate) fn into_inner(self) -> String {
+ self.inner.into_inner().unwrap_or_else(|e| e.into_inner())
+ }
+}
+
+impl fmt::Debug for CaptureBuf {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("CaptureBuf").finish_non_exhaustive()
+ }
+}
+
+impl ConsoleOut for CaptureBuf {
+ fn write_fmt(&self, args: fmt::Arguments<'_>) {
+ let mut s = self.inner.lock().unwrap_or_else(|e| e.into_inner());
+ <String as fmt::Write>::write_fmt(&mut s, args).unwrap();
+ }
+}
