Port the sysroot-crates-are-unstable Python script to rmake

tests/run-make/sysroot-crates-are-unstable/rmake.rs

@@ -1,5 +1,102 @@
-use run_make_support::python_command;
+// Check that crates in the sysroot are treated as unstable, unless they are
+// on a list of known-stable sysroot crates.
+
+use std::path::{Path, PathBuf};
+use std::str;
+
+use run_make_support::{rfs, rustc, target};
+
+fn is_stable_crate(name: &str) -> bool {
+    matches!(name, "std" | "alloc" | "core" | "proc_macro")
+}
 
 fn main() {
-    python_command().arg("test.py").run();
+    for cr in get_unstable_sysroot_crates() {
+        check_crate_is_unstable(&cr);
+    }
+    println!("Done");
+}
+
+#[derive(Debug)]
+struct Crate {
+    name: String,
+    path: PathBuf,
+}
+
+fn check_crate_is_unstable(cr: &Crate) {
+    let Crate { name, path } = cr;
+
+    print!("- Verifying that sysroot crate '{name}' is an unstable crate ...");
+
+    // Trying to use this crate from a user program should fail.
+    let output = rustc()
+        .crate_type("rlib")
+        .target(target())
+        .extern_(name, path)
+        .input("-")
+        .stdin(format!("extern crate {name};"))
+        .run_fail();
+
+    // Make sure it failed for the intended reason, not some other reason.
+    // (The actual feature required varies between crates.)
+    output.assert_stderr_contains("use of unstable library feature");
+
+    println!(" OK");
+}
+
+fn get_unstable_sysroot_crates() -> Vec<Crate> {
+    let sysroot = PathBuf::from(rustc().print("sysroot").run().stdout_utf8().trim());
+    let sysroot_libs_dir = sysroot.join("lib").join("rustlib").join(target()).join("lib");
+    println!("Sysroot libs dir: {sysroot_libs_dir:?}");
+
+    // Generate a list of all library crates in the sysroot.
+    let sysroot_crates = get_all_crates_in_dir(&sysroot_libs_dir);
+    println!(
+        "Found {} sysroot crates: {:?}",
+        sysroot_crates.len(),
+        sysroot_crates.iter().map(|cr| &cr.name).collect::<Vec<_>>()
+    );
+
+    // Self-check: If we didn't find `core`, we probably checked the wrong directory.
+    assert!(
+        sysroot_crates.iter().any(|cr| cr.name == "core"),
+        "Couldn't find `core` in {sysroot_libs_dir:?}"
+    );
+
+    let unstable_sysroot_crates =
+        sysroot_crates.into_iter().filter(|cr| !is_stable_crate(&cr.name)).collect::<Vec<_>>();
+    // Self-check: There should be at least one unstable crate in the directory.
+    assert!(
+        !unstable_sysroot_crates.is_empty(),
+        "Couldn't find any unstable crates in {sysroot_libs_dir:?}"
+    );
+    unstable_sysroot_crates
+}
+
+fn get_all_crates_in_dir(libs_dir: &Path) -> Vec<Crate> {
+    let mut libs = vec![];
+    rfs::read_dir_entries(libs_dir, |path| {
+        if !path.is_file() {
+            return;
+        }
+        if let Some(name) = crate_name_from_path(path) {
+            libs.push(Crate { name, path: path.to_owned() });
+        }
+    });
+    libs.sort_by(|a, b| a.name.cmp(&b.name));
+    libs
+}
+
+/// Treat a file as a crate if its name begins with `lib` and ends with `.rlib`.
+/// The crate name is the part before the first hyphen (if any).
+fn crate_name_from_path(path: &Path) -> Option<String> {
+    let name = path
+        .file_name()?
+        .to_str()?
+        .strip_prefix("lib")?
+        .strip_suffix(".rlib")?
+        .split('-')
+        .next()
+        .expect("split always yields at least one string");
+    Some(name.to_owned())
 }

tests/run-make/sysroot-crates-are-unstable/test.py

@@ -1,75 +0,0 @@
-import sys
-import os
-from os import listdir
-from os.path import isfile, join
-from subprocess import PIPE, Popen
-
-
-# This is n list of files which are stable crates or simply are not crates,
-# we don't check for the instability of these crates as they're all stable!
-STABLE_CRATES = ['std', 'alloc', 'core', 'proc_macro',
-                 'rsbegin.o', 'rsend.o', 'dllcrt2.o', 'crt2.o', 'clang_rt']
-
-
-def convert_to_string(s):
-    if s.__class__.__name__ == 'bytes':
-        return s.decode('utf-8')
-    return s
-
-
-def set_ld_lib_path():
-    var = os.environ.get("LD_LIB_PATH_ENVVAR")
-    rpath = os.environ.get("HOST_RPATH_DIR")
-    if var and rpath:
-        path = os.environ.get(var)
-        if path:
-            os.environ[var] = rpath + os.pathsep + path
-        else:
-            os.environ[var] = rpath
-
-
-def exec_command(command, to_input=None):
-    child = None
-    if to_input is None:
-        child = Popen(command, stdout=PIPE, stderr=PIPE)
-    else:
-        child = Popen(command, stdout=PIPE, stderr=PIPE, stdin=PIPE)
-    stdout, stderr = child.communicate(input=to_input)
-    return (convert_to_string(stdout), convert_to_string(stderr))
-
-
-def check_lib(lib):
-    if lib['name'] in STABLE_CRATES:
-        return True
-    print('verifying if {} is an unstable crate'.format(lib['name']))
-    stdout, stderr = exec_command([os.environ['RUSTC'], '-', '--crate-type', 'rlib',
-                                   '--target', os.environ['TARGET'],
-                                   '--extern', '{}={}'.format(lib['name'], lib['path'])],
-                                  to_input=('extern crate {};'.format(lib['name'])).encode('utf-8'))
-    if 'use of unstable library feature' not in '{}{}'.format(stdout, stderr):
-        print('crate {} "{}" is not unstable'.format(lib['name'], lib['path']))
-        print('{}{}'.format(stdout, stderr))
-        print('')
-        return False
-    return True
-
-# Generate a list of all crates in the sysroot. To do this we list all files in
-# rustc's sysroot, look at the filename, strip everything after the `-`, and
-# strip the leading `lib` (if present)
-def get_all_libs(dir_path):
-    return [{ 'path': join(dir_path, f), 'name': f[3:].split('-')[0] }
-            for f in listdir(dir_path)
-            if isfile(join(dir_path, f)) and f.endswith('.rlib') and f not in STABLE_CRATES]
-
-
-set_ld_lib_path()
-sysroot = exec_command([os.environ['RUSTC'], '--print', 'sysroot'])[0].replace('\n', '')
-assert sysroot, "Could not read the rustc sysroot!"
-libs = get_all_libs(join(sysroot, 'lib/rustlib/{}/lib'.format(os.environ['TARGET'])))
-
-ret = 0
-for lib in libs:
-    if not check_lib(lib):
-        # We continue so users can see all the not unstable crates.
-        ret = 1
-sys.exit(ret)