Support for `--h_out` cmdline parameter.
PiperOrigin-RevId: 475880360
diff --git a/cc_bindings_from_rs/cmdline.rs b/cc_bindings_from_rs/cmdline.rs
new file mode 100644
index 0000000..f93d4a0
--- /dev/null
+++ b/cc_bindings_from_rs/cmdline.rs
@@ -0,0 +1,116 @@
+// Part of the Crubit project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+use getopts::{Fail, Options};
+use std::path::Path;
+
+#[derive(Debug)]
+pub struct Cmdline {
+ h_out: String,
+ rustc_args: Vec<String>,
+}
+
+const H_OUT: &str = "h_out";
+
+impl Cmdline {
+ pub fn new(args: &[String]) -> Result<Self, Fail> {
+ // Ensure that `@file` expansion also covers *our* args.
+ let args = rustc_driver::args::arg_expand_all(args);
+
+ let matches = Options::new()
+ .reqopt("", H_OUT, "output path for C++ header file with bindings", "FILE")
+ .parse(&args)?;
+ let h_out =
+ matches.opt_str(H_OUT).expect("getopts should enforce presence of --h_out `reqopt`");
+
+ Ok(Self { h_out, rustc_args: matches.free })
+ }
+
+ pub fn h_out(&self) -> &Path {
+ Path::new(&self.h_out)
+ }
+
+ pub fn rustc_args(&self) -> &[String] {
+ &self.rustc_args
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ use itertools::Itertools;
+ use std::io::Write;
+ use tempfile::tempdir;
+
+ fn new_cmdline(args: &[&str]) -> Result<Cmdline, Fail> {
+ let args = args.iter().map(|s| s.to_string()).collect_vec();
+ Cmdline::new(&args)
+ }
+
+ #[test]
+ fn test_h_out_happy_path() -> Result<(), Fail> {
+ let cmdline = new_cmdline(&["--h_out=foo.h"])?;
+ assert_eq!(Path::new("foo.h"), cmdline.h_out());
+ Ok(())
+ }
+
+ #[test]
+ fn test_h_out_missing() {
+ match new_cmdline(&[]) {
+ Err(Fail::OptionMissing(arg)) if arg == H_OUT => (),
+ other => panic!("Unexpected success or unrecognized error: {:?}", other),
+ }
+ }
+
+ #[test]
+ fn test_h_out_without_arg() {
+ match new_cmdline(&["--h_out"]) {
+ Err(Fail::ArgumentMissing(arg)) if arg == H_OUT => (),
+ other => panic!("Unexpected success or unrecognized error: {:?}", other),
+ }
+ }
+
+ #[test]
+ fn test_h_out_duplicated() {
+ match new_cmdline(&["--h_out=foo.h", "--h_out=bar.h"]) {
+ Err(Fail::OptionDuplicated(arg)) if arg == H_OUT => (),
+ other => panic!("Unexpected success or unrecognized error: {:?}", other),
+ }
+ }
+
+ #[test]
+ fn test_rustc_args_happy_path() -> Result<(), Fail> {
+ // Note that this test would fail without the `--` separator.
+ let cmdline = new_cmdline(&["--h_out=foo.h", "--", "test.rs", "--crate-type=lib"])?;
+ let rustc_args = cmdline.rustc_args();
+ assert!(
+ itertools::equal(&["test.rs", "--crate-type=lib"], rustc_args),
+ "rustc_args = {:?}",
+ rustc_args
+ );
+ Ok(())
+ }
+
+ #[test]
+ fn test_here_file() -> anyhow::Result<()> {
+ let tmpdir = tempdir()?;
+ let tmpfile = tmpdir.path().join("herefile");
+ let mut f = std::fs::File::create(tmpfile.clone())?;
+ writeln!(f, "--h_out=foo.h")?;
+ writeln!(f, "--")?;
+ writeln!(f, "test.rs")?;
+ writeln!(f, "--crate-type=lib")?;
+
+ let cmdline = Cmdline::new(&[format!("@{}", tmpfile.display())])?;
+ assert_eq!(Path::new("foo.h"), cmdline.h_out());
+ let rustc_args = cmdline.rustc_args();
+ assert!(
+ itertools::equal(&["test.rs", "--crate-type=lib"], rustc_args),
+ "rustc_args = {:?}",
+ rustc_args
+ );
+ Ok(())
+ }
+}
