unexpand: add -f short alias for --first-only

GTimothy · GTimothy · commit ce0c2af497c7 · 2025-06-19T15:21:03.000+02:00
add the `--first-only` alias `-f` expected by busybox.
document the change.
diff --git a/docs/src/extensions.md b/docs/src/extensions.md
@@ -193,3 +193,8 @@ Just like on macOS, `base32/base64/basenc` provides `-D` to decode data.
 ## `shred`
 
 The number of random passes is deterministic in both GNU and uutils. However, uutils `shred` computes the number of random passes in a simplified way, specifically `max(3, x / 10)`, which is very close but not identical to the number of random passes that GNU would do. This also satisfies an expectation that reasonable users might have, namely that the number of random passes increases monotonically with the number of passes overall; GNU `shred` violates this assumption.
+
+## `unexpand`
+
+GNU `unexpand` provides `--first-only` to convert only leading sequences of blanks. We support a
+second way: `-f`.
diff --git a/src/uu/unexpand/src/unexpand.rs b/src/uu/unexpand/src/unexpand.rs
@@ -175,6 +175,7 @@ pub fn uu_app() -> Command {
         )
         .arg(
             Arg::new(options::FIRST_ONLY)
+                .short('f')
                 .long(options::FIRST_ONLY)
                 .help(get_message("unexpand-help-first-only"))
                 .action(ArgAction::SetTrue),

Original file line number	Diff line number	Diff line change
`@@ -175,6 +175,7 @@ pub fn uu_app() -> Command {`
`175`	`175`	`)`
`176`	`176`	`.arg(`
`177`	`177`	`Arg::new(options::FIRST_ONLY)`
	`178`	`+ .short('f')`
`178`	`179`	`.long(options::FIRST_ONLY)`
`179`	`180`	`.help(get_message("unexpand-help-first-only"))`
`180`	`181`	`.action(ArgAction::SetTrue),`