Fix and provide instructions for running test suite on Apple simulators

library/std/src/os/unix/process.rs

@@ -406,8 +406,10 @@ pub trait ChildExt: Sealed {
     /// use libc::SIGTERM;
     ///
     /// fn main() -> io::Result<()> {
+    ///     # if cfg!(not(all(target_vendor = "apple", not(target_os = "macos")))) {
     ///     let child = Command::new("cat").stdin(Stdio::piped()).spawn()?;
     ///     child.send_signal(SIGTERM)?;
+    ///     # }
     ///     Ok(())
     /// }
     /// ```

library/std/src/process.rs

@@ -532,6 +532,7 @@ impl fmt::Debug for ChildStderr {
 /// to be changed (for example, by adding arguments) prior to spawning:
 ///
 /// ```
+/// # if cfg!(not(all(target_vendor = "apple", not(target_os = "macos")))) {
 /// use std::process::Command;
 ///
 /// let output = if cfg!(target_os = "windows") {
@@ -548,6 +549,7 @@ impl fmt::Debug for ChildStderr {
 /// };
 ///
 /// let hello = output.stdout;
+/// # }
 /// ```
 ///
 /// `Command` can be reused to spawn multiple processes. The builder methods
@@ -1348,7 +1350,7 @@ impl Output {
     ///
     /// ```
     /// #![feature(exit_status_error)]
-    /// # #[cfg(all(unix, not(target_os = "android")))] {
+    /// # #[cfg(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos")))))] {
     /// use std::process::Command;
     /// assert!(Command::new("false").output().unwrap().exit_ok().is_err());
     /// # }
@@ -1695,7 +1697,7 @@ impl From<io::Stdout> for Stdio {
     /// # Ok(())
     /// # }
     /// #
-    /// # if cfg!(all(unix, not(target_os = "android"))) {
+    /// # if cfg!(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos"))))) {
     /// #     test().unwrap();
     /// # }
     /// ```
@@ -1724,7 +1726,7 @@ impl From<io::Stderr> for Stdio {
     /// # Ok(())
     /// # }
     /// #
-    /// # if cfg!(all(unix, not(target_os = "android"))) {
+    /// # if cfg!(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos"))))) {
     /// #     test().unwrap();
     /// # }
     /// ```
@@ -1800,7 +1802,7 @@ impl ExitStatus {
     ///
     /// ```
     /// #![feature(exit_status_error)]
-    /// # if cfg!(unix) {
+    /// # if cfg!(all(unix, not(all(target_vendor = "apple", not(target_os = "macos"))))) {
     /// use std::process::Command;
     ///
     /// let status = Command::new("ls")
@@ -1907,7 +1909,7 @@ impl crate::sealed::Sealed for ExitStatusError {}
 ///
 /// ```
 /// #![feature(exit_status_error)]
-/// # if cfg!(all(unix, not(target_os = "android"))) {
+/// # if cfg!(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos"))))) {
 /// use std::process::{Command, ExitStatusError};
 ///
 /// fn run(cmd: &str) -> Result<(), ExitStatusError> {
@@ -1950,7 +1952,7 @@ impl ExitStatusError {
     ///
     /// ```
     /// #![feature(exit_status_error)]
-    /// # #[cfg(all(unix, not(target_os = "android")))] {
+    /// # #[cfg(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos")))))] {
     /// use std::process::Command;
     ///
     /// let bad = Command::new("false").status().unwrap().exit_ok().unwrap_err();
@@ -1975,7 +1977,7 @@ impl ExitStatusError {
     /// ```
     /// #![feature(exit_status_error)]
     ///
-    /// # if cfg!(all(unix, not(target_os = "android"))) {
+    /// # if cfg!(all(unix, not(target_os = "android"), not(all(target_vendor = "apple", not(target_os = "macos"))))) {
     /// use std::num::NonZero;
     /// use std::process::Command;
     ///

library/std/src/process/tests.rs

@@ -5,7 +5,15 @@ use crate::mem::MaybeUninit;
 use crate::str;
 
 fn known_command() -> Command {
-    if cfg!(windows) { Command::new("help") } else { Command::new("echo") }
+    if cfg!(windows) {
+        Command::new("help")
+    } else if cfg!(all(target_vendor = "apple", not(target_os = "macos"))) {
+        // iOS/tvOS/watchOS/visionOS have a very limited set of commandline
+        // binaries available.
+        Command::new("log")
+    } else {
+        Command::new("echo")
+    }
 }
 
 #[cfg(target_os = "android")]
@@ -19,7 +27,10 @@ fn shell_cmd() -> Command {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn smoke() {
     let p = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "exit 0"]).spawn()
@@ -41,7 +52,10 @@ fn smoke_failure() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn exit_reported_right() {
     let p = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "exit 1"]).spawn()
@@ -56,7 +70,10 @@ fn exit_reported_right() {
 
 #[test]
 #[cfg(unix)]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn signal_reported_right() {
     use crate::os::unix::process::ExitStatusExt;
 
@@ -80,7 +97,10 @@ pub fn run_output(mut cmd: Command) -> String {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn stdout_works() {
     if cfg!(target_os = "windows") {
         let mut cmd = Command::new("cmd");
@@ -94,7 +114,11 @@ fn stdout_works() {
 }
 
 #[test]
-#[cfg_attr(any(windows, target_os = "vxworks"), ignore)]
+#[cfg_attr(windows, ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn set_current_dir_works() {
     // On many Unix platforms this will use the posix_spawn path.
     let mut cmd = shell_cmd();
@@ -116,7 +140,11 @@ fn set_current_dir_works() {
 }
 
 #[test]
-#[cfg_attr(any(windows, target_os = "vxworks"), ignore)]
+#[cfg_attr(windows, ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn stdin_works() {
     let mut p = shell_cmd()
         .arg("-c")
@@ -134,7 +162,10 @@ fn stdin_works() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn child_stdout_read_buf() {
     let mut cmd = if cfg!(target_os = "windows") {
         let mut cmd = Command::new("cmd");
@@ -165,7 +196,10 @@ fn child_stdout_read_buf() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_process_status() {
     let mut status = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "exit 1"]).status().unwrap()
@@ -191,7 +225,10 @@ fn test_process_output_fail_to_start() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_process_output_output() {
     let Output { status, stdout, stderr } = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "echo hello"]).output().unwrap()
@@ -206,7 +243,10 @@ fn test_process_output_output() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_process_output_error() {
     let Output { status, stdout, stderr } = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "mkdir ."]).output().unwrap()
@@ -221,7 +261,10 @@ fn test_process_output_error() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_finish_once() {
     let mut prog = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "exit 1"]).spawn().unwrap()
@@ -232,7 +275,10 @@ fn test_finish_once() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_finish_twice() {
     let mut prog = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "exit 1"]).spawn().unwrap()
@@ -244,7 +290,10 @@ fn test_finish_twice() {
 }
 
 #[test]
-#[cfg_attr(any(target_os = "vxworks"), ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_wait_with_output_once() {
     let prog = if cfg!(target_os = "windows") {
         Command::new("cmd").args(&["/C", "echo hello"]).stdout(Stdio::piped()).spawn().unwrap()
@@ -279,7 +328,10 @@ pub fn env_cmd() -> Command {
 }
 
 #[test]
-#[cfg_attr(target_os = "vxworks", ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_override_env() {
     use crate::env;
 
@@ -302,7 +354,10 @@ fn test_override_env() {
 }
 
 #[test]
-#[cfg_attr(target_os = "vxworks", ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_add_to_env() {
     let result = env_cmd().env("RUN_TEST_NEW_ENV", "123").output().unwrap();
     let output = String::from_utf8_lossy(&result.stdout).to_string();
@@ -314,7 +369,10 @@ fn test_add_to_env() {
 }
 
 #[test]
-#[cfg_attr(target_os = "vxworks", ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no shell available"
+)]
 fn test_capture_env_at_spawn() {
     use crate::env;
 
@@ -378,7 +436,10 @@ fn test_interior_nul_in_current_dir_is_error() {
 
 // Regression tests for #30862.
 #[test]
-#[cfg_attr(target_os = "vxworks", ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no `env` cmd available"
+)]
 fn test_interior_nul_in_env_key_is_error() {
     match env_cmd().env("has-some-\0\0s-inside", "value").spawn() {
         Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
@@ -387,7 +448,10 @@ fn test_interior_nul_in_env_key_is_error() {
 }
 
 #[test]
-#[cfg_attr(target_os = "vxworks", ignore)]
+#[cfg_attr(
+    any(target_os = "vxworks", all(target_vendor = "apple", not(target_os = "macos"))),
+    ignore = "no `env` cmd available"
+)]
 fn test_interior_nul_in_env_value_is_error() {
     match env_cmd().env("key", "has-some-\0\0s-inside").spawn() {
         Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),

library/std/src/sys/process/unix/unix/tests.rs

@@ -51,6 +51,7 @@ fn exitstatus_display_tests() {
 
 #[test]
 #[cfg_attr(target_os = "emscripten", ignore)]
+#[cfg_attr(any(target_os = "tvos", target_os = "watchos"), ignore = "fork is prohibited")]
 fn test_command_fork_no_unwind() {
     let got = catch_unwind(|| {
         let mut c = Command::new("echo");

library/std/tests/process_spawning.rs

@@ -7,6 +7,7 @@ mod common;
 #[test]
 // Process spawning not supported by Miri, Emscripten and wasi
 #[cfg_attr(any(miri, target_os = "emscripten", target_os = "wasi"), ignore)]
+#[cfg_attr(any(target_os = "tvos", target_os = "watchos"), ignore = "fork is prohibited")]
 fn issue_15149() {
     // If we're the parent, copy our own binary to a new directory.
     let my_path = env::current_exe().unwrap();

src/doc/rustc-dev-guide/src/tests/running.md

@@ -339,9 +339,34 @@ results.  The Docker image is set up to launch `remote-test-server` and the
 build tools use `remote-test-client` to communicate with the server to
 coordinate running tests (see [src/bootstrap/src/core/build_steps/test.rs]).
 
-> **TODO**
->
-> - Is there any support for using an iOS emulator?
+To run on the iOS/tvOS/watchOS/visionOS simulator, we can similarly treat it as
+a "remote" machine. A curious detail here is that the network is shared between
+the simulator instance and the host macOS, so we can use the local loopback
+address `127.0.0.1`. Something like the following should work:
+
+```sh
+# Build the test server for the iOS simulator:
+./x build src/tools/remote-test-server --target aarch64-apple-ios-sim
+
+# If you already have a simulator instance open, copy the device UUID from:
+xcrun simctl list devices booted
+UDID=01234567-89AB-CDEF-0123-456789ABCDEF
+
+# Alternatively, create and boot a new simulator instance:
+xcrun simctl list runtimes
+xcrun simctl list devicetypes
+UDID=$(xcrun simctl create $CHOSEN_DEVICE_TYPE $CHOSEN_RUNTIME)
+xcrun simctl boot $UDID
+# See https://nshipster.com/simctl/ for details.
+
+# Spawn the runner on port 12345:
+xcrun simctl spawn $UDID ./build/host/stage2-tools/aarch64-apple-ios-sim/release/remote-test-server -v --bind 127.0.0.1:12345
+
+# In a new terminal, run tests via the runner:
+export TEST_DEVICE_ADDR="127.0.0.1:12345"
+./x test --host='' --target aarch64-apple-ios-sim --skip tests/debuginfo
+# FIXME(madsmtm): Allow debuginfo tests to work (maybe needs `.dSYM` folder to be copied to the target?).
+```
 
 [armhf-gnu]: https://github.com/rust-lang/rust/tree/master/src/ci/docker/host-x86_64/armhf-gnu/Dockerfile
 [QEMU]: https://www.qemu.org/