如何使用cargo crate列出项目的源文件？

Question

I'm trying to list the source files of a Rust project using the cargo crate . I can not just simply list all the .rs files present in a directory as I want to retrieve exactly the files that the compiler sees during the compilation, which may not be all the .rs files.

I'm conducting my experiments on the the Alacritty repository , which has a cargo workspace of 3 projects. Here is my code so far:

extern crate cargo;

use std::path::Path;
use cargo::core::Source;

fn main() {
  let path = Path::new("/tmp/alacritty/Cargo.toml");
  let config = cargo::util::config::Config::default().unwrap();

  let ws = cargo::core::Workspace::new(&path, &config).unwrap();

  for pkg in ws.members() {
    println!("found package {}", pkg);

    let config = ws.config();

    let mut src = cargo::sources::PathSource::new(pkg.root(), pkg.package_id().source_id(), config);
    src.update().unwrap();

    let src_files = src.list_files(pkg).unwrap();
    println!("found {} source files", src_files.len());
  }
}

Here is the output:

found package alacritty v0.5.0-dev (/tmp/alacritty/alacritty)
found 0 source files
found package alacritty_terminal v0.5.0-dev (/tmp/alacritty/alacritty_terminal)
found 0 source files
found package font v0.1.0 (/tmp/alacritty/font)
found 0 source files

The members of the workspace are correctly found but I fail to retrieve the source files for each of these members. What am I missing?

Answer 1

Your code works!

If you run 'cargo vendor' in the alacritty tree, this should solve your issue. Study the 'cargo vendor' command Also, study the --offline switch for the cargo build command. I did not need to use this, but it is very helpful reading.

Basically, cargo vendor pulls in all the source.

I am not sure exactly why your code is not working. I had difficulty recreating this using the /tmp directory. I then used a normal directory combined with a call to 'cargo vendor', and it worked. Before cutting and pasting my code below, be sure to change '/Users/[username]' with your own path to your home directory.

Here is my procedure:

cd ~
git clone https://github.com/jwilm/alacritty
cargo vendor

This next part is probably not necessary:

mkdir /Users/[username]/alacritty/.cargo

Create a file at /Users/[username]/alacritty/.cargo/config and, insert the following:

[source.crates-io]
replace-with = "vendored-sources"

[source.vendored-sources]
directory = "vendor"

Continuation of necessary part:

Modify the path statement to point to the newly created alacritty path:

    let path = Path::new("/Users/[username]/alacritty/Cargo.toml");

Now, run your code

    cargo run

Here is my output:

cargo run
    Finished dev [unoptimized + debuginfo] target(s) in 0.27s
     Running `target/debug/test3`
found package alacritty v0.5.0-dev (/Users/jmurray/alacritty/alacritty)
found 18 source files
found package alacritty_terminal v0.5.0-dev 
(/Users/[username]/alacritty/alacritty_terminal)
found 172 source files
found package font v0.1.0 (/Users/jmurray/alacritty/font)
found 12 source files

Answer 2

Search for each element of the needle in the haystack in order. Each time you find a matching element, only continue the search in the remaining portion of the haystack. You can express this nicely by taking a new subslice of of the haystack each time you match an element.