cargo.rs

  1use super::DapLocator;
  2use anyhow::{Result, anyhow};
  3use async_trait::async_trait;
  4use dap::DebugAdapterConfig;
  5use serde_json::{Value, json};
  6use smol::{
  7    io::AsyncReadExt,
  8    process::{Command, Stdio},
  9};
 10use util::maybe;
 11
 12pub(super) struct CargoLocator;
 13
 14#[async_trait]
 15impl DapLocator for CargoLocator {
 16    async fn run_locator(&self, debug_config: &mut DebugAdapterConfig) -> Result<()> {
 17        let Some(launch_config) = (match &mut debug_config.request {
 18            task::DebugRequestDisposition::UserConfigured(task::DebugRequestType::Launch(
 19                launch_config,
 20            )) => Some(launch_config),
 21            _ => None,
 22        }) else {
 23            return Err(anyhow!("Couldn't get launch config in locator"));
 24        };
 25
 26        let Some(cwd) = launch_config.cwd.clone() else {
 27            return Err(anyhow!(
 28                "Couldn't get cwd from debug config which is needed for locators"
 29            ));
 30        };
 31
 32        let mut child = Command::new("cargo")
 33            .args(&launch_config.args)
 34            .arg("--message-format=json")
 35            .current_dir(cwd)
 36            .stdout(Stdio::piped())
 37            .spawn()?;
 38
 39        let mut output = String::new();
 40        if let Some(mut stdout) = child.stdout.take() {
 41            stdout.read_to_string(&mut output).await?;
 42        }
 43
 44        let status = child.status().await?;
 45        if !status.success() {
 46            return Err(anyhow::anyhow!("Cargo command failed"));
 47        }
 48
 49        let Some(executable) = output
 50            .lines()
 51            .filter(|line| !line.trim().is_empty())
 52            .filter_map(|line| serde_json::from_str(line).ok())
 53            .find_map(|json: Value| {
 54                json.get("executable")
 55                    .and_then(Value::as_str)
 56                    .map(String::from)
 57            })
 58        else {
 59            return Err(anyhow!("Couldn't get executable in cargo locator"));
 60        };
 61
 62        launch_config.program = executable;
 63        let mut test_name = None;
 64
 65        if launch_config
 66            .args
 67            .first()
 68            .map_or(false, |arg| arg == "test")
 69        {
 70            if let Some(package_index) = launch_config
 71                .args
 72                .iter()
 73                .position(|arg| arg == "-p" || arg == "--package")
 74            {
 75                test_name = launch_config
 76                    .args
 77                    .get(package_index + 2)
 78                    .filter(|name| !name.starts_with("--"))
 79                    .cloned();
 80            }
 81        }
 82
 83        if debug_config.adapter == "LLDB" && debug_config.initialize_args.is_none() {
 84            // Find Rust pretty-printers in current toolchain's sysroot
 85            let cwd = launch_config.cwd.clone();
 86            debug_config.initialize_args = maybe!(async move {
 87                let cwd = cwd?;
 88
 89                let output = Command::new("rustc")
 90                    .arg("--print")
 91                    .arg("sysroot")
 92                    .current_dir(cwd)
 93                    .output()
 94                    .await
 95                    .ok()?;
 96
 97                if !output.status.success() {
 98                    return None;
 99                }
100
101                let sysroot_path = String::from_utf8(output.stdout).ok()?;
102                let sysroot_path = sysroot_path.trim_end();
103                let first_command = format!(
104                    r#"command script import "{sysroot_path}/lib/rustlib/etc/lldb_lookup.py"#
105                );
106                let second_command =
107                    format!(r#"command source -s 0 '{sysroot_path}/lib/rustlib/etc/lldb_commands"#);
108
109                Some(json!({"initCommands": [first_command, second_command]}))
110            })
111            .await;
112        }
113
114        launch_config.args.clear();
115        if let Some(test_name) = test_name {
116            launch_config.args.push(test_name);
117        }
118        Ok(())
119    }
120}