implement --fast and --slow

src/cli/args.rs

@@ -61,8 +61,18 @@ pub enum Subcommand {
         output: PathBuf,
 
         /// Compression level, applied to all formats
-        #[arg(short, long)]
+        #[arg(short, long, group = "compression-level")]
         level: Option<i16>,
+
+        /// Fastest compression level possible,
+        /// conflicts with --level and --slow
+        #[arg(long, group = "compression-level")]
+        fast: bool,
+
+        /// Slowest (and best) compression level possible,
+        /// conflicts with --level and --fast
+        #[arg(long, group = "compression-level")]
+        slow: bool,
     },
     /// Decompresses one or more files, optionally into another folder
     #[command(visible_alias = "d")]

src/commands/mod.rs

@@ -45,6 +45,8 @@ pub fn run(
             files,
             output: output_path,
             level,
+            fast,
+            slow,
         } => {
             // After cleaning, if there are no input files left, exit
             if files.is_empty() {
@@ -81,7 +83,13 @@ pub fn run(
                 args.quiet,
                 question_policy,
                 file_visibility_policy,
-                level,
+                if fast {
+                    Some(0)
+                } else if slow {
+                    Some(i16::MAX)
+                } else {
+                    level
+                },
             );
 
             if let Ok(true) = compress_result {