fix: resolve compilation errors by adding Sync+Send bounds and fixing syntax

Co-authored-by: aider (openai/andrew/openrouter/sonoma-sky-alpha) <aider@aider.chat>

src/compression_engine.rs

@@ -61,7 +61,7 @@ pub enum CompressionType {
 /// let engine = /* some engine */;
 /// let reader = engine.open("file.gz".into()).unwrap();
 /// ```
-pub trait CompressionEngine {
+pub trait CompressionEngine: Send + Sync {
     /// Opens a compressed file for reading.
     ///
     /// Creates a reader that transparently decompresses the file contents as they are read.
@@ -156,22 +156,32 @@ pub trait CompressionEngine {
         writer.flush()?;
         Ok(())
     }
+
+    /// Clones this compression engine into a new boxed instance.
+    ///
+    /// Required for dynamic trait object cloning.
+    ///
+    /// # Returns
+    ///
+    /// A new `Box<dyn CompressionEngine>` clone of this engine.
+    fn clone_box(&self) -> Box<dyn CompressionEngine>;
+}
+
+impl Clone for Box<dyn CompressionEngine> {
+    fn clone(&self) -> Self {
+        self.as_ref().clone_box()
+    }
 }
 
 lazy_static! {
     static ref COMPRESSION_ENGINES: EnumMap<CompressionType, Box<dyn CompressionEngine>> = {
-        enum_map! {
+        let mut em = enum_map! {
             CompressionType::LZ4 => Box::new(crate::compression_engine::lz4::CompressionEngineLZ4::new()),
-            CompressionType::GZip => {
-                #[cfg(feature = "gzip")]
-                Box::new(crate::compression_engine::gzip::CompressionEngineGZip::new()),
-                #[cfg(not(feature = "gzip"))]
-                Box::new(crate::compression_engine::program::CompressionEngineProgram::new(
-                    "gzip",
-                    vec!["-c"],
-                    vec!["-d", "-c"]
-                ))
-            },
+            CompressionType::GZip => Box::new(crate::compression_engine::program::CompressionEngineProgram::new(
+                "gzip",
+                vec!["-c"],
+                vec!["-d", "-c"]
+            )),
             CompressionType::BZip2 => Box::new(crate::compression_engine::program::CompressionEngineProgram::new(
                 "bzip2",
                 vec!["-c"],
@@ -188,7 +198,14 @@ lazy_static! {
                 vec!["-d", "-c"]
             )),
             CompressionType::None => Box::new(crate::compression_engine::none::CompressionEngineNone::new())
+        };
+
+        #[cfg(feature = "gzip")]
+        {
+            em[CompressionType::GZip] = Box::new(crate::compression_engine::gzip::CompressionEngineGZip::new());
         }
+
+        em
     };
 }