pull function out into new crate ra_env; use in ra_flycheck as well

Cargo.lock

@@ -999,6 +999,14 @@ dependencies = [
  "test_utils",
 ]
 
+[[package]]
+name = "ra_env"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "dirs",
+]
+
 [[package]]
 name = "ra_flycheck"
 version = "0.1.0"
@@ -1009,6 +1017,7 @@ dependencies = [
  "jod-thread",
  "log",
  "lsp-types",
+ "ra_env",
  "serde_json",
 ]
 
@@ -1209,11 +1218,11 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "cargo_metadata",
- "dirs",
  "log",
  "ra_arena",
  "ra_cfg",
  "ra_db",
+ "ra_env",
  "ra_proc_macro",
  "rustc-hash",
  "serde",

crates/ra_env/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+edition = "2018"
+name = "ra_env"
+version = "0.1.0"
+authors = ["rust-analyzer developers"]
+
+[dependencies]
+anyhow = "1.0.26"
+dirs = "2.0"

crates/ra_env/src/lib.rs

@@ -13,7 +13,7 @@ pub fn get_path_for_executable(executable_name: impl AsRef<str>) -> Result<Strin
     // 1) Appropriate environment variable (erroring if this is set but not a usable executable)
     //      example: for cargo, this checks $CARGO environment variable; for rustc, $RUSTC; etc
     // 2) `<executable_name>`
-    //      example: for cargo, this tries just `cargo`, which will succeed if `cargo` in on the $PATH
+    //      example: for cargo, this tries just `cargo`, which will succeed if `cargo` is on the $PATH
     // 3) `~/.cargo/bin/<executable_name>`
     //      example: for cargo, this tries ~/.cargo/bin/cargo
     //      It seems that this is a reasonable place to try for cargo, rustc, and rustup

crates/ra_flycheck/Cargo.toml

@@ -14,6 +14,7 @@ log = "0.4.8"
 cargo_metadata = "0.9.1"
 serde_json = "1.0.48"
 jod-thread = "0.1.1"
+ra_env = { path = "../ra_env" }
 
 [dev-dependencies]
 insta = "0.16.0"

crates/ra_flycheck/src/lib.rs

@@ -4,7 +4,6 @@
 mod conv;
 
 use std::{
-    env,
     io::{self, BufRead, BufReader},
     path::PathBuf,
     process::{Command, Stdio},
@@ -17,6 +16,7 @@ use lsp_types::{
     CodeAction, CodeActionOrCommand, Diagnostic, Url, WorkDoneProgress, WorkDoneProgressBegin,
     WorkDoneProgressEnd, WorkDoneProgressReport,
 };
+use ra_env::get_path_for_executable;
 
 use crate::conv::{map_rust_diagnostic_to_lsp, MappedRustDiagnostic};
 
@@ -216,7 +216,7 @@ impl FlycheckThread {
 
         let mut cmd = match &self.config {
             FlycheckConfig::CargoCommand { command, all_targets, all_features, extra_args } => {
-                let mut cmd = Command::new(cargo_binary());
+                let mut cmd = Command::new(get_path_for_executable("cargo").unwrap());
                 cmd.arg(command);
                 cmd.args(&["--workspace", "--message-format=json", "--manifest-path"]);
                 cmd.arg(self.workspace_root.join("Cargo.toml"));
@@ -337,7 +337,3 @@ fn run_cargo(
 
     Ok(())
 }
-
-fn cargo_binary() -> String {
-    env::var("CARGO").unwrap_or_else(|_| "cargo".to_string())
-}

crates/ra_project_model/Cargo.toml

@@ -14,13 +14,12 @@ rustc-hash = "1.1.0"
 cargo_metadata = "0.9.1"
 
 ra_arena = { path = "../ra_arena" }
-ra_db = { path = "../ra_db" }
 ra_cfg = { path = "../ra_cfg" }
+ra_db = { path = "../ra_db" }
+ra_env = { path = "../ra_env" }
 ra_proc_macro =  { path = "../ra_proc_macro" }
 
 serde = { version = "1.0.106", features = ["derive"] }
 serde_json = "1.0.48"
 
 anyhow = "1.0.26"
-
-dirs = "2.0"

crates/ra_project_model/src/cargo_workspace.rs

@@ -7,11 +7,11 @@ use std::{
     process::Command,
 };
 
-use super::find_executables::get_path_for_executable;
 use anyhow::{Context, Result};
 use cargo_metadata::{BuildScript, CargoOpt, Message, MetadataCommand, PackageId};
 use ra_arena::{Arena, Idx};
 use ra_db::Edition;
+use ra_env::get_path_for_executable;
 use rustc_hash::FxHashMap;
 
 /// `CargoWorkspace` represents the logical structure of, well, a Cargo

crates/ra_project_model/src/lib.rs

@@ -1,7 +1,6 @@
 //! FIXME: write short doc here
 
 mod cargo_workspace;
-mod find_executables;
 mod json_project;
 mod sysroot;
 
@@ -15,6 +14,7 @@ use std::{
 use anyhow::{bail, Context, Result};
 use ra_cfg::CfgOptions;
 use ra_db::{CrateGraph, CrateName, Edition, Env, ExternSource, ExternSourceId, FileId};
+use ra_env::get_path_for_executable;
 use rustc_hash::FxHashMap;
 use serde_json::from_reader;
 
@@ -559,7 +559,7 @@ pub fn get_rustc_cfg_options(target: Option<&String>) -> CfgOptions {
 
     match (|| -> Result<String> {
         // `cfg(test)` and `cfg(debug_assertion)` are handled outside, so we suppress them here.
-        let mut cmd = Command::new("rustc");
+        let mut cmd = Command::new(get_path_for_executable("rustc")?);
         cmd.args(&["--print", "cfg", "-O"]);
         if let Some(target) = target {
             cmd.args(&["--target", target.as_str()]);

crates/ra_project_model/src/sysroot.rs

@@ -1,6 +1,5 @@
 //! FIXME: write short doc here
 
-use super::find_executables::get_path_for_executable;
 use anyhow::{bail, Context, Result};
 use std::{
     env, ops,
@@ -9,6 +8,7 @@ use std::{
 };
 
 use ra_arena::{Arena, Idx};
+use ra_env::get_path_for_executable;
 
 #[derive(Default, Debug, Clone)]
 pub struct Sysroot {
@@ -122,7 +122,8 @@ fn get_or_install_rust_src(cargo_toml: &Path) -> Result<PathBuf> {
     let src_path = sysroot_path.join("lib/rustlib/src/rust/src");
 
     if !src_path.exists() {
-        run_command_in_cargo_dir(cargo_toml, "rustup", &["component", "add", "rust-src"])?;
+        let rustup = get_path_for_executable("rustup")?;
+        run_command_in_cargo_dir(cargo_toml, &rustup, &["component", "add", "rust-src"])?;
     }
     if !src_path.exists() {
         bail!(