Add the match subcommand.

source/cli/mod.rs

@@ -51,6 +51,13 @@ pub enum MainSubcommand {
     #[arg(short, long, default_value = "bautils.log")]
     file: String,
   },
+
+  /// The match subcommand.
+  Match {
+    /// The match subcommands.
+    #[command(subcommand)]
+    command: MatchSubcommand,
+  },
 }
 
 /// The arguments subcommands.
@@ -110,3 +117,20 @@ pub enum FileSubcommand {
     file: PathBuf,
   },
 }
+
+/// The match subcommands.
+#[derive(Debug, Subcommand)]
+pub enum MatchSubcommand {
+  /// Match a given string to a regular expression pattern, if the pattern
+  /// matches the exit code will be 0, otherwise it will be 1. Regular
+  /// expression parsing failures will intentionally cause a panic.
+  Regex {
+    /// The regular expression to match with.
+    #[arg(short, long)]
+    pattern: String,
+
+    /// The string to test.
+    #[arg()]
+    string: String,
+  },
+}

source/cli/run.rs

@@ -4,7 +4,7 @@ use {
   crate::{
     cli::{
       ArgumentsSubcommand, Cli, DirectorySubcommand, FileSubcommand,
-      MainSubcommand::*, Parser,
+      MainSubcommand::*, MatchSubcommand, Parser,
     },
     logging::append_line_to_file,
   },
@@ -87,5 +87,16 @@ pub fn run() {
       println!("{}", log_line);
       append_line_to_file(&file, &log_line).unwrap();
     }
+
+    Match {
+      command: match_subcommand,
+    } => match match_subcommand {
+      MatchSubcommand::Regex { pattern, string } => {
+        let regex = regex::RegexBuilder::new(&pattern).build().unwrap();
+        if !regex.is_match(&string) {
+          std::process::exit(1);
+        }
+      }
+    },
   }
 }