build(rust): vendor googletest crate

third_party/crates/autocfg-1.5.1/tests/wrappers.rs

@@ -0,0 +1,83 @@
+extern crate autocfg;
+
+use std::env;
+use std::io;
+
+mod support;
+
+fn main() {
+    let args: Vec<_> = env::args().skip(1).collect();
+    if args.is_empty() {
+        // With no arguments, this must be a (harness-free) test run.
+        // (we're using system binaries as wrappers, so ignore other platforms)
+        if cfg!(unix) {
+            test_wrappers();
+        }
+    } else {
+        // Otherwise we're acting like a no-op rustc wrapper, ignoring almost everything.
+        for arg in args {
+            match &*arg {
+                // Add our own version so we can check that the wrapper is used for that.
+                "--version" => println!("release: 12345.6789.0"),
+
+                // Read all input so the writer doesn't get EPIPE when we exit.
+                "-" => {
+                    let stdin = io::stdin();
+                    let _ = io::copy(&mut stdin.lock(), &mut io::sink());
+                }
+
+                _ => {}
+            }
+        }
+    }
+}
+
+/// Tests that autocfg uses the RUSTC_WRAPPER and/or RUSTC_WORKSPACE_WRAPPER
+/// environment variables when running rustc.
+fn test_wrappers() {
+    fn set(name: &str, value: Option<bool>) {
+        match value {
+            Some(true) => env::set_var(name, "/usr/bin/env"),
+            Some(false) => env::set_var(name, "/bin/false"),
+            None => env::remove_var(name),
+        }
+    }
+
+    let out = support::out_dir();
+
+    // This is used as a heuristic to detect rust-lang/cargo#9601.
+    env::set_var("CARGO_ENCODED_RUSTFLAGS", "");
+
+    // No wrapper, a good pass-through wrapper, and a bad wrapper.
+    let variants = [None, Some(true), Some(false)];
+
+    for &workspace in &variants {
+        for &rustc in &variants {
+            set("RUSTC_WRAPPER", rustc);
+            set("RUSTC_WORKSPACE_WRAPPER", workspace);
+
+            let ac = autocfg::AutoCfg::with_dir(out.as_ref()).unwrap();
+            if rustc == Some(false) || workspace == Some(false) {
+                // Everything should fail with bad wrappers.
+                assert!(!ac.probe_type("usize"));
+            } else {
+                // Try known good and bad types for the wrapped rustc.
+                assert!(ac.probe_type("usize"));
+                assert!(!ac.probe_type("mesize"));
+            }
+            // Either way, we should have found the inner rustc version.
+            assert!(ac.probe_rustc_version(1, 0));
+        }
+    }
+
+    // Finally, make sure that `RUSTC_WRAPPER` is applied outermost
+    // by using something (ourself) that doesn't pass through at all.
+    let wrap_ignored = env::current_exe().unwrap();
+    env::set_var("RUSTC_WRAPPER", &wrap_ignored);
+    env::set_var("RUSTC_WORKSPACE_WRAPPER", "/bin/false");
+    let ac = autocfg::AutoCfg::with_dir(out.as_ref()).unwrap();
+    assert!(ac.probe_type("mesize")); // anything goes!
+
+    // Make sure we also got the version from that wrapper.
+    assert!(ac.probe_rustc_version(12345, 6789));
+}