1 //! This will build the proc macro in `imp`, and copy the resulting dylib artifact into the
2 //! `OUT_DIR`.
3 //!
4 //! `proc_macro_test` itself contains only a path to that artifact.
5 
6 use std::{
7     env, fs,
8     path::{Path, PathBuf},
9     process::Command,
10 };
11 
12 use cargo_metadata::Message;
13 
main()14 fn main() {
15     let out_dir = env::var_os("OUT_DIR").unwrap();
16     let out_dir = Path::new(&out_dir);
17 
18     let name = "proc_macro_test_impl";
19     let version = "0.0.0";
20     let target_dir = out_dir.join("target");
21     let output = Command::new(toolchain::cargo())
22         .current_dir("imp")
23         .args(&["build", "-p", "proc_macro_test_impl", "--message-format", "json"])
24         // Explicit override the target directory to avoid using the same one which the parent
25         // cargo is using, or we'll deadlock.
26         // This can happen when `CARGO_TARGET_DIR` is set or global config forces all cargo
27         // instance to use the same target directory.
28         .arg("--target-dir")
29         .arg(&target_dir)
30         .output()
31         .unwrap();
32     assert!(output.status.success());
33 
34     let mut artifact_path = None;
35     for message in Message::parse_stream(output.stdout.as_slice()) {
36         match message.unwrap() {
37             Message::CompilerArtifact(artifact) => {
38                 if artifact.target.kind.contains(&"proc-macro".to_string()) {
39                     let repr = format!("{} {}", name, version);
40                     if artifact.package_id.repr.starts_with(&repr) {
41                         artifact_path = Some(PathBuf::from(&artifact.filenames[0]));
42                     }
43                 }
44             }
45             _ => (), // Unknown message
46         }
47     }
48 
49     // This file is under `target_dir` and is already under `OUT_DIR`.
50     let artifact_path = artifact_path.expect("no dylib for proc_macro_test_impl found");
51 
52     let info_path = out_dir.join("proc_macro_test_location.txt");
53     fs::write(info_path, artifact_path.to_str().unwrap()).unwrap();
54 }
55