Update GitHub Actions actions/checkout@v2 to v3

[rust.git] / build.rs

diff --git a/build.rs b/build.rs
index ac27db564939f1bd2b614dcd72c59d407323372f..e7b1e1b854c07025ac06e9391859c2c1c7fd63af 100644 (file)
--- a/build.rs
+++ b/build.rs
@@ -1,28 +1,55 @@
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// Build script. Just copies default.toml from the src to the target dir.
-
 use std::env;
+use std::fs::File;
+use std::io::Write;
 use std::path::{Path, PathBuf};
+use std::process::Command;
 
 fn main() {
-    let in_file = Path::new("src/default.toml");
+    // Only check .git/HEAD dirty status if it exists - doing so when
+    // building dependent crates may lead to false positives and rebuilds
+    if Path::new(".git/HEAD").exists() {
+        println!("cargo:rerun-if-changed=.git/HEAD");
+    }
+
+    println!("cargo:rerun-if-env-changed=CFG_RELEASE_CHANNEL");
+
+    let out_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
+
+    File::create(out_dir.join("commit-info.txt"))
+        .unwrap()
+        .write_all(commit_info().as_bytes())
+        .unwrap();
+}
 
-    let manifest_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
-    let profile = env::var("PROFILE").unwrap();
-    let mut out_file = PathBuf::new();
-    out_file.push(manifest_dir);
-    out_file.push("target");
-    out_file.push(profile);
-    out_file.push("default.toml");
+// Try to get hash and date of the last commit on a best effort basis. If anything goes wrong
+// (git not installed or if this is not a git repository) just return an empty string.
+fn commit_info() -> String {
+    match (channel(), commit_hash(), commit_date()) {
+        (channel, Some(hash), Some(date)) => format!("{} ({} {})", channel, hash.trim_end(), date),
+        _ => String::new(),
+    }
+}
+
+fn channel() -> String {
+    if let Ok(channel) = env::var("CFG_RELEASE_CHANNEL") {
+        channel
+    } else {
+        "nightly".to_owned()
+    }
+}
+
+fn commit_hash() -> Option<String> {
+    Command::new("git")
+        .args(&["rev-parse", "--short", "HEAD"])
+        .output()
+        .ok()
+        .and_then(|r| String::from_utf8(r.stdout).ok())
+}
 
-    std::fs::copy(in_file, out_file).unwrap();
+fn commit_date() -> Option<String> {
+    Command::new("git")
+        .args(&["log", "-1", "--date=short", "--pretty=format:%cd"])
+        .output()
+        .ok()
+        .and_then(|r| String::from_utf8(r.stdout).ok())
 }