add in-memory tests

Author: dsherret

.github/workflows/rust.yml

@@ -97,6 +97,9 @@ jobs:
       # Run the ignored tests that expect the above setup
       - name: Build | Test
         run: cargo test --workspace --all-features -- --include-ignored
+
+      - name: Test (no default features)
+        run: cargo test --workspace --no-default-features
   cargo-deny:
     runs-on: ubuntu-22.04
     steps:

src/lib.rs

@@ -6,12 +6,14 @@
 //! To find which rustc executable binary is using:
 //!
 //! ```no_run
+//! # #[cfg(feature = "real-sys")]
+//! # {
 //! use which::which;
 //! use std::path::PathBuf;
 //!
 //! let result = which("rustc").unwrap();
 //! assert_eq!(result, PathBuf::from("/usr/bin/rustc"));
-//!
+//! # }
 //! ```
 
 #![forbid(unsafe_code)]
@@ -411,6 +413,8 @@ impl<'a, TSys: Sys, F: NonFatalErrorHandler + 'a> WhichConfig<TSys, F> {
     ///
     /// # Example
     /// ```
+    /// # #[cfg(feature = "real-sys")]
+    /// # {
     /// # use which::WhichConfig;
     /// let mut nonfatal_errors = Vec::new();
     ///
@@ -424,18 +428,22 @@ impl<'a, TSys: Sys, F: NonFatalErrorHandler + 'a> WhichConfig<TSys, F> {
     /// if !nonfatal_errors.is_empty() {
     ///     println!("nonfatal errors encountered: {nonfatal_errors:?}");
     /// }
+    /// # }
     /// ```
     ///
     /// You could also log it if you choose
     ///
     /// ```
+    /// # #[cfg(feature = "real-sys")]
+    /// # {
     /// # use which::WhichConfig;
     /// WhichConfig::new()
     ///     .binary_name("tar".into())
     ///     .nonfatal_error_handler(|e| eprintln!("{e}"))
     ///     .all_results()
     ///     .unwrap()
     ///     .collect::<Vec<_>>();
+    /// # }
     /// ```
     pub fn nonfatal_error_handler<NewF>(self, handler: NewF) -> WhichConfig<TSys, NewF> {
         WhichConfig {

src/sys.rs

@@ -79,11 +79,13 @@ pub trait Sys: Clone {
     /// and isn't conditionally compiled with `#[cfg(windows)]` so that it
     /// can work in Wasm.
     fn env_windows_path_ext(&self) -> Cow<'static, [String]> {
-        Cow::Owned(self.env_var(OsStr::new("PATHEXT"))
-            .map(|pathext| { parse_path_ext(&pathext) })
-            // PATHEXT not being set or not being a proper Unicode string is exceedingly
-            // improbable and would probably break Windows badly. Still, don't crash:
-            .unwrap_or_default())
+        Cow::Owned(
+            self.env_var(OsStr::new("PATHEXT"))
+                .map(|pathext| parse_path_ext(&pathext))
+                // PATHEXT not being set or not being a proper Unicode string is exceedingly
+                // improbable and would probably break Windows badly. Still, don't crash:
+                .unwrap_or_default(),
+        )
     }
     /// Gets the metadata of the provided path, following symlinks.
     fn metadata(&self, path: &Path) -> io::Result<Self::Metadata>;
@@ -233,14 +235,14 @@ impl Sys for RealSys {
 
 fn parse_path_ext(pathext: &str) -> Vec<String> {
     pathext
-    .split(';')
-    .filter_map(|s| {
-        if s.as_bytes().first() == Some(&b'.') {
-            Some(s.to_owned())
-        } else {
-            // Invalid segment; just ignore it.
-            None
-        }
-    })
-    .collect()
-}
+        .split(';')
+        .filter_map(|s| {
+            if s.as_bytes().first() == Some(&b'.') {
+                Some(s.to_owned())
+            } else {
+                // Invalid segment; just ignore it.
+                None
+            }
+        })
+        .collect()
+}