Add --detect-terminal option

CHANGELOG.md

@@ -8,6 +8,9 @@ To publish a new release run `scripts/release` from the project directory.
 
 ## [Unreleased]
 
+### Added
+- Add `--detect-terminal` to print the name of the detected terminal program (see [GH-232]).
+
 ### Changed
 
 - Replace `ureq` with `reqwest` (see [GH-229]).

mdcat.1.adoc

@@ -100,7 +100,10 @@ This is the default when run as `mdcat`.
 
 --fail::
     Fail immediately at the first FILE which fails to read.
-    By default mdcat continues with the next file.
+    By default, mdcat continues with the next file.
+
+--detect-terminal::
+    Detect the terminal program, print its name, and exit.
 
 -h::
 --help::

src/bin/mdcat/args.rs

@@ -98,9 +98,9 @@ pub struct CommonArgs {
     /// Exit immediately if any error occurs processing an input file.
     #[arg(long = "fail")]
     pub fail_fast: bool,
-    /// Only detect the terminal type and exit.
-    #[arg(long, hide = true)]
-    pub detect_only: bool,
+    /// Print detected terminal name and exit.
+    #[arg(long = "detect-terminal")]
+    pub detect_and_exit: bool,
     /// Limit to standard ANSI formatting.
     #[arg(long, conflicts_with = "no_colour", hide = true)]
     pub ansi_only: bool,

src/bin/mdcat/main.rs

@@ -112,7 +112,7 @@ fn main() {
         TerminalProgram::detect()
     };
 
-    if args.detect_only {
+    if args.detect_and_exit {
         println!("Terminal: {}", terminal_app);
     } else {
         // On Windows 10 we need to enable ANSI term explicitly.