1 files changed, 136 insertions, 0 deletions
diff --git a/testing/geckodriver/build.rs b/testing/geckodriver/build.rs
new file mode 100644
index 0000000000..eb590476b7
--- /dev/null
+++ b/testing/geckodriver/build.rs
@@ -0,0 +1,136 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Writes build information to ${OUT_DIR}/build-info.rs which is included in
+// the program during compilation:
+//
+// ```no_run
+// const COMMIT_HASH: Option<&'static str> = Some("c31a366");
+// const COMMIT_DATE: Option<&'static str> = Some("1988-05-10");
+// ```
+//
+// The values are `None` if running hg failed, e.g. if it is not installed or
+// if we are not in an hg repo.
+
+use std::env;
+use std::ffi::OsStr;
+use std::fs::File;
+use std::io;
+use std::io::Write;
+use std::path::{Path, PathBuf};
+use std::process::Command;
+
+fn main() -> io::Result<()> {
+    let cur_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+    let build_info = get_build_info(&cur_dir);
+
+    let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
+    let mut fh = File::create(out_dir.join("build-info.rs"))?;
+    writeln!(
+        fh,
+        "const COMMIT_HASH: Option<&'static str> = {:?};",
+        build_info.hash()
+    )?;
+    writeln!(
+        fh,
+        "const COMMIT_DATE: Option<&'static str> = {:?};",
+        build_info.date()
+    )?;
+
+    Ok(())
+}
+
+fn get_build_info(dir: &Path) -> Box<dyn BuildInfo> {
+    if Path::exists(&dir.join(".hg")) {
+        Box::new(Hg {})
+    } else if Path::exists(&dir.join(".git")) {
+        Box::new(Git {})
+    } else if let Some(parent) = dir.parent() {
+        get_build_info(parent)
+    } else {
+        eprintln!("unable to detect vcs");
+        Box::new(Noop {})
+    }
+}
+
+trait BuildInfo {
+    fn hash(&self) -> Option<String>;
+    fn date(&self) -> Option<String>;
+}
+
+struct Hg;
+
+impl Hg {
+    fn exec<I, S>(&self, args: I) -> Option<String>
+    where
+        I: IntoIterator<Item = S>,
+        S: AsRef<OsStr>,
+    {
+        Command::new("hg")
+            .env("HGPLAIN", "1")
+            .args(args)
+            .output()
+            .ok()
+            .and_then(|r| String::from_utf8(r.stdout).ok())
+            .map(|s| s.trim_end().into())
+    }
+}
+
+impl BuildInfo for Hg {
+    fn hash(&self) -> Option<String> {
+        self.exec(["log", "-r.", "-T{node|short}"])
+    }
+
+    fn date(&self) -> Option<String> {
+        self.exec(["log", "-r.", "-T{date|isodate}"])
+    }
+}
+
+struct Git;
+
+impl Git {
+    fn exec<I, S>(&self, args: I) -> Option<String>
+    where
+        I: IntoIterator<Item = S>,
+        S: AsRef<OsStr>,
+    {
+        Command::new("git")
+            .env("GIT_CONFIG_NOSYSTEM", "1")
+            .args(args)
+            .output()
+            .ok()
+            .and_then(|r| String::from_utf8(r.stdout).ok())
+            .map(|s| s.trim_end().into())
+    }
+
+    fn to_hg_sha(&self, git_sha: String) -> Option<String> {
+        self.exec(["cinnabar", "git2hg", &git_sha])
+    }
+}
+
+impl BuildInfo for Git {
+    fn hash(&self) -> Option<String> {
+        self.exec(["rev-parse", "HEAD"])
+            .and_then(|sha| self.to_hg_sha(sha))
+            .map(|mut s| {
+                s.truncate(12);
+                s
+            })
+    }
+
+    fn date(&self) -> Option<String> {
+        self.exec(["log", "-1", "--date=short", "--pretty=format:%cd"])
+    }
+}
+
+struct Noop;
+
+impl BuildInfo for Noop {
+    fn hash(&self) -> Option<String> {
+        None
+    }
+    fn date(&self) -> Option<String> {
+        None
+    }
+}