handle Code::multiline_continue_from result

src/line/code/error.rs

@@ -0,0 +1,16 @@
+use std::fmt::{Display, Formatter, Result};
+
+#[derive(Debug)]
+pub enum Error {
+    Multiline(crate::line::code::multiline::Error),
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut Formatter) -> Result {
+        match self {
+            Self::Multiline(e) => {
+                write!(f, "Multiline error: {e}")
+            }
+        }
+    }
+}

src/line/code/multiline.rs

@@ -1,3 +1,6 @@
+pub mod error;
+pub use error::Error;
+
 use glib::GString;
 
 pub struct Multiline {
@@ -28,10 +31,10 @@ impl Multiline {
 
     /// Continue preformatted buffer from line,
     /// set `completed` as True on close tag found
-    pub fn continue_from(&mut self, line: &str) {
+    pub fn continue_from(&mut self, line: &str) -> Result<(), Error> {
         // Make sure buffer not completed yet
         if self.completed {
-            panic!("Could not continue as completed") // @TODO handle
+            return Err(Error::Completed);
         }
 
         // Line contain close tag
@@ -42,5 +45,7 @@ impl Multiline {
         // Append data to the buffer, trim close tag on exists
         self.buffer
             .push(GString::from(line.trim_end_matches("```")));
+
+        Ok(())
     }
 }

src/line/code/multiline/error.rs

@@ -0,0 +1,16 @@
+use std::fmt::{Display, Formatter, Result};
+
+#[derive(Debug)]
+pub enum Error {
+    Completed,
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut Formatter) -> Result {
+        match self {
+            Self::Completed => {
+                write!(f, "Could not continue as completed!")
+            }
+        }
+    }
+}