Auto merge of #11754 - kylematsuda:more-config-env, r=ehuss

Make more reads of environment variables go through the `Config`

As discussed in #11588, it's better to make reads of environment variables go through the `Config` instead of calling `std::env::var` or `env::var_os` everywhere.

Most of the "easy" places to change this in `src/` were handled in #11727. This PR fixes a few remaining call sites that were missed in #11727, namely:

- `LocalFingerprint::find_stale_item`
- `util::profile::start` and `Profiler`
- `util::rustc::rustc_fingerprint`

After doing this, there are a few remaining calls to `env::var` in `src/` but those probably require more discussion to fix.

src/cargo/core/compiler/fingerprint/mod.rs

@@ -371,7 +371,7 @@ use crate::util;
 use crate::util::errors::CargoResult;
 use crate::util::interning::InternedString;
 use crate::util::{internal, path_args, profile, StableHasher};
-use crate::CARGO_ENV;
+use crate::{Config, CARGO_ENV};
 
 use super::custom_build::BuildDeps;
 use super::job::{Job, Work};
@@ -782,6 +782,7 @@ impl LocalFingerprint {
         pkg_root: &Path,
         target_root: &Path,
         cargo_exe: &Path,
+        config: &Config,
     ) -> CargoResult<Option<StaleItem>> {
         match self {
             // We need to parse `dep_info`, learn about the crate's dependencies.
@@ -810,7 +811,7 @@ impl LocalFingerprint {
                                 .to_string(),
                         )
                     } else {
-                        env::var(key).ok()
+                        config.get_env(key).ok()
                     };
                     if current == *previous {
                         continue;
@@ -1059,6 +1060,7 @@ impl Fingerprint {
         pkg_root: &Path,
         target_root: &Path,
         cargo_exe: &Path,
+        config: &Config,
     ) -> CargoResult<()> {
         assert!(!self.fs_status.up_to_date());
 
@@ -1166,7 +1168,7 @@ impl Fingerprint {
         // message and bail out so we stay stale.
         for local in self.local.get_mut().unwrap().iter() {
             if let Some(item) =
-                local.find_stale_item(mtime_cache, pkg_root, target_root, cargo_exe)?
+                local.find_stale_item(mtime_cache, pkg_root, target_root, cargo_exe, config)?
             {
                 item.log();
                 self.fs_status = FsStatus::StaleItem(item);
@@ -1328,6 +1330,7 @@ fn calculate(cx: &mut Context<'_, '_>, unit: &Unit) -> CargoResult<Arc<Fingerpri
         unit.pkg.root(),
         &target_root,
         cargo_exe,
+        cx.bcx.config,
     )?;
 
     let fingerprint = Arc::new(fingerprint);

src/cargo/util/config/mod.rs

@@ -426,6 +426,7 @@ impl Config {
             } else {
                 None
             },
+            self,
         )
     }
 

src/cargo/util/rustc.rs

@@ -10,7 +10,7 @@ use log::{debug, info, warn};
 use serde::{Deserialize, Serialize};
 
 use crate::util::interning::InternedString;
-use crate::util::{profile, CargoResult, StableHasher};
+use crate::util::{profile, CargoResult, Config, StableHasher};
 
 /// Information on the `rustc` executable
 #[derive(Debug)]
@@ -43,6 +43,7 @@ impl Rustc {
         workspace_wrapper: Option<PathBuf>,
         rustup_rustc: &Path,
         cache_location: Option<PathBuf>,
+        config: &Config,
     ) -> CargoResult<Rustc> {
         let _p = profile::start("Rustc::new");
 
@@ -52,6 +53,7 @@ impl Rustc {
             &path,
             rustup_rustc,
             cache_location,
+            config,
         );
 
         let mut cmd = ProcessBuilder::new(&path);
@@ -173,10 +175,11 @@ impl Cache {
         rustc: &Path,
         rustup_rustc: &Path,
         cache_location: Option<PathBuf>,
+        config: &Config,
     ) -> Cache {
         match (
             cache_location,
-            rustc_fingerprint(wrapper, workspace_wrapper, rustc, rustup_rustc),
+            rustc_fingerprint(wrapper, workspace_wrapper, rustc, rustup_rustc, config),
         ) {
             (Some(cache_location), Ok(rustc_fingerprint)) => {
                 let empty = CacheData {
@@ -296,6 +299,7 @@ fn rustc_fingerprint(
     workspace_wrapper: Option<&Path>,
     rustc: &Path,
     rustup_rustc: &Path,
+    config: &Config,
 ) -> CargoResult<u64> {
     let mut hasher = StableHasher::new();
 
@@ -329,8 +333,8 @@ fn rustc_fingerprint(
     let maybe_rustup = rustup_rustc == rustc;
     match (
         maybe_rustup,
-        env::var("RUSTUP_HOME"),
-        env::var("RUSTUP_TOOLCHAIN"),
+        config.get_env("RUSTUP_HOME"),
+        config.get_env("RUSTUP_TOOLCHAIN"),
     ) {
         (_, Ok(rustup_home), Ok(rustup_toolchain)) => {
             debug!("adding rustup info to rustc fingerprint");