diff --git a/src/cli.rs b/src/cli.rs
index 4eb31f6..0b38cab 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -37,8 +37,8 @@ pub fn parse_args() -> crate::Result<ParsedArgs> {
     match &mut parsed_args.command {
         Command::Compress { files, .. } | Command::Decompress { files, .. } => {
             *files = canonicalize_files(&files)?;
-        },
-        _ => {},
+        }
+        _ => {}
     }
     Ok(parsed_args)
 }
@@ -72,7 +72,7 @@ fn canonicalize(path: impl AsRef<Path>) -> crate::Result<PathBuf> {
             } else {
                 Err(io_err.into())
             }
-        },
+        }
     }
 }
 
@@ -107,7 +107,7 @@ pub fn parse_args_from(mut args: Vec<OsString>) -> crate::Result<ParsedArgs> {
 
             let command = Command::Compress { files, compressed_output_path };
             ParsedArgs { command, flags }
-        },
+        }
         // Defaults to decompression when there is no subcommand
         None => {
             flags_info.push(arg_flag!('o', "output"));
@@ -121,18 +121,71 @@ pub fn parse_args_from(mut args: Vec<OsString>) -> crate::Result<ParsedArgs> {
             }
 
             // Parse flags
-            let (files, mut flags) = oof::filter_flags(args, &flags_info)?;
+            let (files, flags) = oof::filter_flags(args, &flags_info)?;
             let files = files.into_iter().map(PathBuf::from).collect();
 
-            let output_folder = flags.take_arg("output").map(PathBuf::from);
+            let output_folder = flags.arg("output").map(PathBuf::from);
 
             // TODO: ensure all files are decompressible
 
             let command = Command::Decompress { files, output_folder };
             ParsedArgs { command, flags }
-        },
+        }
         _ => unreachable!("You should match each subcommand passed."),
     };
 
     Ok(parsed_args)
 }
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    fn gen_args(text: &str) -> Vec<OsString> {
+        let args = text.split_whitespace();
+        args.map(OsString::from).collect()
+    }
+
+    fn test_cli(args: &str) -> crate::Result<ParsedArgs> {
+        let args = gen_args(args);
+        parse_args_from(args)
+    }
+
+    #[test]
+    fn test_cli_commands() {
+        assert_eq!(test_cli("--help").unwrap().command, Command::ShowHelp);
+        assert_eq!(test_cli("--version").unwrap().command, Command::ShowVersion);
+        assert_eq!(test_cli("--version").unwrap().flags, oof::Flags::default());
+        assert_eq!(
+            test_cli("foo.zip bar.zip").unwrap().command,
+            Command::Decompress {
+                files: vec!["foo.zip".into(), "bar.zip".into()],
+                output_folder: None
+            }
+        );
+        assert_eq!(
+            test_cli("compress foo bar baz.zip").unwrap().command,
+            Command::Compress {
+                files: vec!["foo".into(), "bar".into()],
+                compressed_output_path: "baz.zip".into()
+            }
+        );
+        assert_eq!(test_cli("compress").unwrap_err(), crate::Error::MissingArgumentsForCompression);
+    }
+
+    #[test]
+    fn test_cli_flags() {
+        // --help and --version flags are considered commands that are ran over anything else
+        assert_eq!(test_cli("--help").unwrap().flags, oof::Flags::default());
+        assert_eq!(test_cli("--version").unwrap().flags, oof::Flags::default());
+
+        assert_eq!(
+            test_cli("foo --yes bar --output folder").unwrap().flags,
+            oof::Flags {
+                boolean_flags: vec!["yes"].into_iter().collect(),
+                argument_flags: vec![("output", OsString::from("folder"))].into_iter().collect(),
+            }
+        );
+    }
+}
diff --git a/src/oof/flags.rs b/src/oof/flags.rs
index b70af33..7ff1a78 100644
--- a/src/oof/flags.rs
+++ b/src/oof/flags.rs
@@ -55,9 +55,7 @@ impl Flags {
     pub fn new() -> Self {
         Self::default()
     }
-}
 
-impl Flags {
     pub fn is_present(&self, flag_name: &str) -> bool {
         self.boolean_flags.contains(flag_name) || self.argument_flags.contains_key(flag_name)
     }