Refactor serverEnv, rustcSysroot async/await

Author: alexheretic

lib/index.js

@@ -91,19 +91,18 @@ function installCompiler() {
 
 /**
  * @param {string} toolchain
- * @return {string} `rustc --print sysroot` stdout
+ * @return {Promise<string>} `rustc --print sysroot` stdout
  */
-function rustcSysroot(toolchain) {
-  return cp.execSync(`rustup run ${toolchain} rustc --print sysroot`, {
-    env: { PATH: getPath() }
-  }).toString().trim()
+async function rustcSysroot(toolchain) {
+  let { stdout } = await exec(`rustup run ${toolchain} rustc --print sysroot`)
+  return stdout.trim()
 }
 
 /**
  * @param {string} [toolchain]
- * @return {object} environment vars
+ * @return {Promise<object>} environment vars
  */
-function serverEnv(toolchain) {
+async function serverEnv(toolchain) {
   const env = {
     PATH: getPath(),
     RUST_BACKTRACE: '1',
@@ -116,7 +115,8 @@ function serverEnv(toolchain) {
 
   if (toolchain) {
     try {
-      env.RUST_SRC_PATH = path.join(rustcSysroot(toolchain), "/lib/rustlib/src/rust/src/")
+      let sysroot = await rustcSysroot(toolchain)
+      env.RUST_SRC_PATH = path.join(sysroot, "/lib/rustlib/src/rust/src/")
     }
     catch (e) {
       console.error("Failed to find sysroot: " + e)
@@ -511,7 +511,7 @@ class RustLanguageClient extends AutoLanguageClient {
         this._warnedAboutRlsCommandOverride = true
       }
       return cp.spawn(cmdOverride, {
-        env: serverEnv(configToolchain()),
+        env: await serverEnv(configToolchain()),
         shell: true,
         cwd: projectPath
       })
@@ -522,7 +522,7 @@ class RustLanguageClient extends AutoLanguageClient {
       await checkRls(this.busySignalService)
       let toolchain = configToolchain()
       return cp.spawn("rustup", ["run", toolchain, "rls"], {
-        env: serverEnv(toolchain),
+        env: await serverEnv(toolchain),
         cwd: projectPath
       })
     }