fix: autogenerate version string correctly in CI

Cargo.toml

@@ -21,7 +21,7 @@ anstyle = "1.0.8"
 anyhow = "1.0.89"
 capnp = "0.20.1"
 capnp-futures = "0.20.0"
-clap = { version = "4.5.19", features = ["wrap_help", "derive", "cargo", "help"] }
+clap = { version = "4.5.19", features = ["wrap_help", "derive", "cargo", "help", "string"] }
 console = "0.15.8"
 dns-lookup = "2.0.4"
 futures-util = { version = "0.3.31", default-features = false }
@@ -44,7 +44,6 @@ tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
 nix = { version = "0.29.0", features = ["socket"] }
 
 [build-dependencies]
-built = { version = "0.7.4", features = ["git2"] }
 capnpc = "0.20.0"
 
 [dev-dependencies]

build.rs

@@ -1,7 +1,7 @@
 #![allow(missing_docs)]
 
 fn main() {
-    built::write_built_file().expect("Failed to acquire build-time information");
+    process_version_string();
 
     capnpc::CompilerCommand::new()
         .src_prefix("schema")
@@ -17,3 +17,41 @@ fn main() {
         .run()
         .expect("control protocol compiler command");
 }
+
+fn process_version_string() {
+    let hash = git_short_hash().unwrap();
+    println!("cargo:rustc-env=QCP_BUILD_GIT_HASH={hash}");
+    let cargo_version = env!("CARGO_PKG_VERSION");
+
+    let version_string = if let Some(tag) = github_tag() {
+        // This is a tagged build running in CI
+        println!("cargo:rustc-env=QCP_CI_TAG_VERSION={tag}");
+        // Sanity check. We tag releases as "v1.2.3", so strip off the leading v before matching.
+        let short_tag = tag.strip_prefix("v").unwrap_or(&tag);
+        assert_eq!(
+            cargo_version, short_tag,
+            "mismatched cargo and CI version tags"
+        );
+        tag
+    } else {
+        format!("{cargo_version}+g{hash}")
+    };
+    println!("cargo:rustc-env=QCP_VERSION_STRING={version_string}");
+}
+
+fn github_tag() -> Option<String> {
+    std::env::var("GITHUB_REF_TYPE")
+        .is_ok_and(|v| v == "tag")
+        .then(|| std::env::var("GITHUB_REF_NAME").unwrap())
+}
+
+fn git_short_hash() -> Option<String> {
+    use std::process::Command;
+    let args = &["rev-parse", "--short=8", "HEAD"];
+    let output = Command::new("git").args(args).output().unwrap();
+    let rev = String::from_utf8_lossy(&output.stdout).trim().to_string();
+    if rev.is_empty() {
+        return None;
+    }
+    Some(rev)
+}

src/cli/args.rs

@@ -1,17 +1,15 @@
 // QCP top-level command-line arguments
 // (c) 2024 Ross Younger
 
-use crate::build_info;
-use clap::Parser;
+use clap::{Args as _, FromArgMatches as _, Parser};
 
 /// Options that switch us into another mode i.e. which don't require source/destination arguments
 pub(crate) const MODE_OPTIONS: &[&str] = &["server", "help_buffers"];
 
 #[derive(Debug, Parser, Clone)]
 #[command(
     author,
-    version,
-    version(build_info::GIT_VERSION),
+    // we set short/long version strings explicitly, see custom_parse()
     about,
     before_help = "e.g.   qcp some/file my-server:some-directory/",
     infer_long_args(true)
@@ -70,3 +68,12 @@ pub(crate) struct CliArgs {
     //
     // N.B. ClientOptions has positional arguments!
 }
+
+impl CliArgs {
+    /// Sets up and executes ou
+    pub(crate) fn custom_parse() -> Self {
+        let cli = clap::Command::new(clap::crate_name!());
+        let cli = CliArgs::augment_args(cli).version(crate::version::short());
+        CliArgs::from_arg_matches(&cli.get_matches_from(std::env::args_os())).unwrap()
+    }
+}

src/cli/cli_main.rs

@@ -11,7 +11,6 @@ use crate::{
     server::server_main,
     util::setup_tracing,
 };
-use clap::Parser;
 use indicatif::{MultiProgress, ProgressDrawTarget};
 use tracing::error_span;
 
@@ -23,7 +22,7 @@ use tracing::error_span;
 #[tokio::main(flavor = "current_thread")]
 #[allow(clippy::missing_panics_doc)]
 pub async fn cli() -> anyhow::Result<ExitCode> {
-    let args = CliArgs::parse();
+    let args = CliArgs::custom_parse();
     if args.help_buffers {
         os::print_udp_buffer_size_help_message(
             args.bandwidth.recv_buffer(),

src/lib.rs

@@ -66,8 +66,4 @@ pub mod doc;
 
 pub mod os;
 
-/// Build-time info (autogenerated by `built`)
-#[allow(unreachable_pub)]
-mod build_info {
-    include!(concat!(env!("OUT_DIR"), "/built.rs"));
-}
+mod version;

src/version.rs

@@ -0,0 +1,12 @@
+//! Autogenerated build-time information
+// (c) 2024 Ross Younger
+
+/// Short version string
+pub(crate) fn short() -> String {
+    // this _should_ be provided by our build script; if not, something went wrong
+    if let Some(v) = option_env!("QCP_VERSION_STRING") {
+        return v.to_string();
+    }
+    let hash = option_env!("QCP_BUILD_GIT_HASH").unwrap_or("???");
+    format!("{}+g{hash}", env!("CARGO_PKG_VERSION"))
+}