escape: add quote detection

src/escapeapp.rs

@@ -14,6 +14,7 @@ enum EscType {
 }
 
 const SHELL_CHARS: &[u8; 4] = b"`$\"\\";
+
 // Note that bash is crazy regarding '!'
 // echo "\!" will output \!
 // ref: https://www.gnu.org/software/bash/manual/html_node/Double-Quotes.html
@@ -65,6 +66,7 @@ impl SliceEsc for [u8] {
 pub struct EscapeApplet {
     esc_type: EscType,
     no_quote: bool,
+    no_detect: bool,
     multiline: bool,
 }
 
@@ -80,6 +82,7 @@ impl Applet for EscapeApplet {
         Command::new(self.command())
             .about(self.description())
             .arg(arg!(-m --multiline "expect multiline string, do not trim input"))
+            .arg(arg!(-d --"no-detect" "do not detect surrounding quotes"))
             .arg(arg!(-n --"no-quote" "do not wrap output in quotes"))
             .arg(
                 arg!(-t --type [type] "type of escape")
@@ -93,6 +96,7 @@ impl Applet for EscapeApplet {
         Ok(Box::new(Self {
             esc_type: args.get_one::<EscType>("type").unwrap().clone(),
             no_quote: args.get_flag("no-quote"),
+            no_detect: args.get_flag("no-detect"),
             multiline: args.get_flag("multiline"),
         }))
     }
@@ -103,18 +107,39 @@ impl Applet for EscapeApplet {
         } else {
             val.trim().into()
         };
-        let escaped = to_escape.escape(&self.esc_type);
-        if self.no_quote {
+
+        // Detect (unless no_detect) surrounding quotes to:
+        //  - remove them
+        //  - escape
+        //  - restore them
+        let (quote, to_escape_nq) = if !self.no_detect {
+            let first = *to_escape.first().unwrap_or(&b' ');
+            let last = *to_escape.last().unwrap_or(&b'*');
+
+            if first != last {
+                (None, to_escape.clone())
+            } else {
+                let end_pos = to_escape.len() - 1;
+                match first {
+                    b'\'' => (Some(b'\''), to_escape[1..end_pos].to_vec()),
+                    b'"' => (Some(b'"'), to_escape[1..end_pos].to_vec()),
+                    _ => (None, to_escape),
+                }
+            }
+        } else {
+            match self.esc_type {
+                EscType::BashSingle | EscType::Single => (Some(b'\''), to_escape),
+                _ => (Some(b'"'), to_escape),
+            }
+        };
+        let escaped = to_escape_nq.escape(&self.esc_type);
+        if self.no_quote || quote.is_none() {
             Ok(escaped)
         } else {
-            let quote = match self.esc_type {
-                EscType::BashSingle | EscType::Single => b'\'',
-                _ => b'"',
-            };
             let mut res = Vec::<u8>::with_capacity(escaped.len() + 2);
-            res.push(quote);
+            res.push(quote.unwrap());
             res.extend(escaped);
-            res.push(quote);
+            res.push(quote.unwrap());
             Ok(res)
         }
     }
@@ -123,6 +148,7 @@ impl Applet for EscapeApplet {
         Box::new(Self {
             esc_type: EscType::Generic,
             no_quote: false,
+            no_detect: false,
             multiline: false,
         })
     }