refactor(monorepo): expose one workspace path API

src/monorepo/workspace.rs

@@ -1,13 +1,13 @@
 use std::path::PathBuf;
 
 pub fn resolve_workspace_path(path: PathBuf) -> PathBuf {
-    resolve_workspace_path_from(
+    resolve_workspace_path_impl(
         path,
         std::env::var_os("BUILD_WORKSPACE_DIRECTORY").map(PathBuf::from),
     )
 }
 
-pub fn resolve_workspace_path_from(path: PathBuf, workspace: Option<PathBuf>) -> PathBuf {
+fn resolve_workspace_path_impl(path: PathBuf, workspace: Option<PathBuf>) -> PathBuf {
     if path.is_absolute() {
         return path;
     }

src/monorepo/workspace_test.rs

@@ -1,31 +1,86 @@
+use std::ffi::OsString;
 use std::path::PathBuf;
+use std::sync::Mutex;
 
-use monorepo::workspace::resolve_workspace_path_from;
+use monorepo::workspace::resolve_workspace_path;
+
+static ENV_LOCK: Mutex<()> = Mutex::new(());
+
+const BUILD_WORKSPACE_DIRECTORY: &str = "BUILD_WORKSPACE_DIRECTORY";
+
+struct EnvRestore {
+    key: &'static str,
+    value: Option<OsString>,
+}
+
+impl EnvRestore {
+    fn set(key: &'static str, value: &str) -> Self {
+        let restore = Self {
+            key,
+            value: std::env::var_os(key),
+        };
+
+        unsafe {
+            std::env::set_var(key, value);
+        }
+
+        restore
+    }
+
+    fn remove(key: &'static str) -> Self {
+        let restore = Self {
+            key,
+            value: std::env::var_os(key),
+        };
+
+        unsafe {
+            std::env::remove_var(key);
+        }
+
+        restore
+    }
+}
+
+impl Drop for EnvRestore {
+    fn drop(&mut self) {
+        unsafe {
+            if let Some(value) = &self.value {
+                std::env::set_var(self.key, value);
+            } else {
+                std::env::remove_var(self.key);
+            }
+        }
+    }
+}
 
 #[test]
 fn absolute_path_returns_unchanged_path() {
+    let _lock = ENV_LOCK.lock().unwrap();
+    let _workspace = EnvRestore::set(BUILD_WORKSPACE_DIRECTORY, "/workspace");
     let path = PathBuf::from("/tmp/output");
 
-    let resolved = resolve_workspace_path_from(path.clone(), Some(PathBuf::from("/workspace")));
+    let resolved = resolve_workspace_path(path.clone());
 
     assert_eq!(resolved, path);
 }
 
 #[test]
 fn relative_path_joins_workspace_path() {
-    let resolved = resolve_workspace_path_from(
-        PathBuf::from("output/graph"),
-        Some(PathBuf::from("/workspace")),
-    );
+    let _lock = ENV_LOCK.lock().unwrap();
+    let _workspace = EnvRestore::set(BUILD_WORKSPACE_DIRECTORY, "/workspace");
+
+    let resolved = resolve_workspace_path(PathBuf::from("output/graph"));
 
     assert_eq!(resolved, PathBuf::from("/workspace/output/graph"));
 }
 
 #[test]
 fn relative_path_without_workspace_returns_unchanged_path() {
+    let _lock = ENV_LOCK.lock().unwrap();
+    let _workspace = EnvRestore::remove(BUILD_WORKSPACE_DIRECTORY);
     let path = PathBuf::from("output/graph");
 
-    let resolved = resolve_workspace_path_from(path.clone(), None);
+    let resolved = resolve_workspace_path(path.clone());
 
     assert_eq!(resolved, path);
 }