Align toolchain version fetching with other toolchain info querying

Fix --target flag argument order in rustc_cfg fetching

crates/project-model/src/lib.rs

@@ -20,6 +20,7 @@ pub mod toolchain_info {
     pub mod rustc_cfg;
     pub mod target_data_layout;
     pub mod target_tuple;
+    pub mod version;
 
     use std::path::Path;
 

crates/project-model/src/toolchain_info/rustc_cfg.rs

@@ -68,10 +68,10 @@ fn rustc_print_cfg(
             cmd.envs(extra_env);
             cmd.env("RUSTC_BOOTSTRAP", "1");
             cmd.args(["rustc", "-Z", "unstable-options"]).args(RUSTC_ARGS);
-            cmd.args(["--", "-O"]);
             if let Some(target) = target {
                 cmd.args(["--target", target]);
             }
+            cmd.args(["--", "-O"]);
 
             match utf8_stdout(&mut cmd) {
                 Ok(it) => return Ok(it),

crates/project-model/src/toolchain_info/version.rs

@@ -0,0 +1,32 @@
+//! Get the version string of the toolchain.
+
+use anyhow::Context;
+use rustc_hash::FxHashMap;
+use semver::Version;
+use toolchain::Tool;
+
+use crate::{toolchain_info::QueryConfig, utf8_stdout};
+
+pub(crate) fn get(
+    config: QueryConfig<'_>,
+    extra_env: &FxHashMap<String, String>,
+) -> Result<Option<Version>, anyhow::Error> {
+    let (mut cmd, prefix) = match config {
+        QueryConfig::Cargo(sysroot, cargo_toml) => {
+            (sysroot.tool(Tool::Cargo, cargo_toml.parent()), "cargo ")
+        }
+        QueryConfig::Rustc(sysroot, current_dir) => {
+            (sysroot.tool(Tool::Rustc, current_dir), "rustc ")
+        }
+    };
+    cmd.envs(extra_env);
+    cmd.arg("--version");
+    let out = utf8_stdout(&mut cmd).with_context(|| format!("Failed to query rust toolchain version via `{cmd:?}`, is your toolchain setup correctly?"))?;
+
+    let version =
+        out.strip_prefix(prefix).and_then(|it| Version::parse(it.split_whitespace().next()?).ok());
+    if version.is_none() {
+        tracing::warn!("Failed to parse `{cmd:?}` output `{out}` as a semver version");
+    }
+    anyhow::Ok(version)
+}

crates/project-model/src/workspace.rs

@@ -26,7 +26,7 @@ use crate::{
     env::{cargo_config_env, inject_cargo_env, inject_cargo_package_env, inject_rustc_tool_env},
     project_json::{Crate, CrateArrayIdx},
     sysroot::{SysrootCrate, SysrootMode},
-    toolchain_info::{rustc_cfg, target_data_layout, target_tuple, QueryConfig},
+    toolchain_info::{rustc_cfg, target_data_layout, target_tuple, version, QueryConfig},
     utf8_stdout, CargoConfig, CargoWorkspace, CfgOverrides, InvocationStrategy, ManifestPath,
     Package, ProjectJson, ProjectManifest, Sysroot, TargetData, TargetKind, WorkspaceBuildScripts,
 };
@@ -150,27 +150,6 @@ impl fmt::Debug for ProjectWorkspace {
     }
 }
 
-fn get_toolchain_version(
-    current_dir: &AbsPath,
-    sysroot: &Sysroot,
-    tool: Tool,
-    extra_env: &FxHashMap<String, String>,
-    prefix: &str,
-) -> Result<Option<Version>, anyhow::Error> {
-    let cargo_version = utf8_stdout(&mut {
-        let mut cmd = Sysroot::tool(sysroot, tool, current_dir);
-        cmd.envs(extra_env);
-        cmd.arg("--version");
-        cmd
-    })
-    .with_context(|| format!("Failed to query rust toolchain version at {current_dir}, is your toolchain setup correctly?"))?;
-    anyhow::Ok(
-        cargo_version
-            .get(prefix.len()..)
-            .and_then(|it| Version::parse(it.split_whitespace().next()?).ok()),
-    )
-}
-
 impl ProjectWorkspace {
     pub fn load(
         manifest: ProjectManifest,
@@ -249,12 +228,10 @@ impl ProjectWorkspace {
                 .ok_or_else(|| Some("Failed to discover rustc source for sysroot.".to_owned())),
             None => Err(None),
         };
-        let targets = target_tuple::get(
-            QueryConfig::Cargo(&sysroot, cargo_toml),
-            config.target.as_deref(),
-            &config.extra_env,
-        )
-        .unwrap_or_default();
+        let toolchain_config = QueryConfig::Cargo(&sysroot, cargo_toml);
+        let targets =
+            target_tuple::get(toolchain_config, config.target.as_deref(), &config.extra_env)
+                .unwrap_or_default();
         let rustc = rustc_dir.and_then(|rustc_dir| {
             info!(workspace = %cargo_toml, rustc_dir = %rustc_dir, "Using rustc source");
             match CargoWorkspace::fetch_metadata(
@@ -291,21 +268,19 @@ impl ProjectWorkspace {
                 }
             }
         });
-        let toolchain = get_toolchain_version(
-            cargo_toml.parent(),
-            &sysroot,
-            Tool::Cargo,
-            &config.extra_env,
-            "cargo ",
-        )?;
-        let rustc_cfg = rustc_cfg::get(
-            QueryConfig::Cargo(&sysroot, cargo_toml),
-            targets.first().map(Deref::deref),
-            &config.extra_env,
-        );
+        let toolchain = version::get(toolchain_config, &config.extra_env)
+            .inspect_err(|e| {
+                tracing::error!(%e,
+                    "failed fetching toolchain version for {cargo_toml:?} workspace"
+                )
+            })
+            .ok()
+            .flatten();
+        let rustc_cfg =
+            rustc_cfg::get(toolchain_config, targets.first().map(Deref::deref), &config.extra_env);
         let cfg_overrides = config.cfg_overrides.clone();
         let data_layout = target_data_layout::get(
-            QueryConfig::Cargo(&sysroot, cargo_toml),
+            toolchain_config,
             targets.first().map(Deref::deref),
             &config.extra_env,
         );
@@ -355,19 +330,7 @@ impl ProjectWorkspace {
             &config.sysroot_query_metadata,
         );
         let query_config = QueryConfig::Rustc(&sysroot, project_json.path().as_ref());
-        let toolchain = match get_toolchain_version(
-            project_json.path(),
-            &sysroot,
-            Tool::Rustc,
-            &config.extra_env,
-            "rustc ",
-        ) {
-            Ok(it) => it,
-            Err(e) => {
-                tracing::error!("{e}");
-                None
-            }
-        };
+        let toolchain = version::get(query_config, &config.extra_env).ok().flatten();
 
         let target = config.target.as_deref();
         let rustc_cfg = rustc_cfg::get(query_config, target, &config.extra_env);
@@ -397,22 +360,10 @@ impl ProjectWorkspace {
             None => Sysroot::empty(),
         };
 
-        let toolchain =
-            match get_toolchain_version(dir, &sysroot, Tool::Rustc, &config.extra_env, "rustc ") {
-                Ok(it) => it,
-                Err(e) => {
-                    tracing::error!("{e}");
-                    None
-                }
-            };
-
-        let targets = target_tuple::get(
-            QueryConfig::Cargo(&sysroot, detached_file),
-            config.target.as_deref(),
-            &config.extra_env,
-        )
-        .unwrap_or_default();
-        let query_config = QueryConfig::Rustc(&sysroot, dir.as_ref());
+        let query_config = QueryConfig::Cargo(&sysroot, detached_file);
+        let toolchain = version::get(query_config, &config.extra_env).ok().flatten();
+        let targets = target_tuple::get(query_config, config.target.as_deref(), &config.extra_env)
+            .unwrap_or_default();
         let rustc_cfg = rustc_cfg::get(query_config, None, &config.extra_env);
         let data_layout = target_data_layout::get(query_config, None, &config.extra_env);