Add a way to disable dll copying for users of proc_macro_srv library

Author: vlad20012

crates/proc_macro_srv/Cargo.toml

@@ -30,3 +30,7 @@ expect-test = "1.2.0-pre.1"
 
 # used as proc macro test targets
 proc_macro_test = { path = "../proc_macro_test" }
+
+[features]
+default = ["copy-dll-on-windows"]
+copy-dll-on-windows = [] # Please keep the feature (or another way to disable DLL copying) for intellij-rust

crates/proc_macro_srv/src/dylib.rs

@@ -162,7 +162,7 @@ impl Expander {
 }
 
 /// Copy the dylib to temp directory to prevent locking in Windows
-#[cfg(windows)]
+#[cfg(all(windows, feature = "copy-dll-on-windows"))]
 fn ensure_file_with_lock_free_access(path: &Path) -> io::Result<PathBuf> {
     use std::collections::hash_map::RandomState;
     use std::ffi::OsString;
@@ -189,7 +189,7 @@ fn ensure_file_with_lock_free_access(path: &Path) -> io::Result<PathBuf> {
     Ok(to)
 }
 
-#[cfg(unix)]
+#[cfg(any(unix, not(feature = "copy-dll-on-windows")))]
 fn ensure_file_with_lock_free_access(path: &Path) -> io::Result<PathBuf> {
     Ok(path.to_path_buf())
 }