Set cancel return type to result

src/calc.rs

@@ -205,7 +205,8 @@ impl<'a> Calculator<'a> {
 
                 for c in value.chars() {
                     self.take_input(c).map_err(|e| {
-                        self.cancel();
+                        // Try cancelling, but if you cannot, that is okay
+                        self.cancel().unwrap_or(());
                         e
                     })?;
                 }
@@ -239,9 +240,15 @@ impl<'a> Calculator<'a> {
         }
     }
 
-    pub fn cancel(&mut self) {
+    pub fn cancel(&mut self) -> CalculatorResult<()> {
         self.state = CalculatorState::Normal;
-        self.active_macros.clear();
+        // We died in a macro. Quit and push an end macro state
+        if !self.active_macros.is_empty() {
+            self.active_macros.clear();
+            // Should always be successful, but report the error if there is one
+            self.op(CalculatorOperation::Macro(MacroState::End))?;
+        }
+        Ok(())
     }
     pub fn backspace(&mut self) -> CalculatorResult<()> {
         self.l.pop();

src/main.rs

@@ -268,7 +268,7 @@ fn handle_key(app: &mut App, events: &Events, key: Key) -> CalculatorResult<bool
         (AppState::Help, _) => match key {
             Key::Esc | Key::Char('q') => {
                 app.state = AppState::Calculator;
-                app.calculator.cancel();
+                app.calculator.cancel()?;
             }
             _ => {}
         },
@@ -277,7 +277,7 @@ fn handle_key(app: &mut App, events: &Events, key: Key) -> CalculatorResult<bool
         | (AppState::Calculator, CalculatorState::WaitingForMacro) => match key {
             Key::Esc => {
                 app.state = AppState::Calculator;
-                app.calculator.cancel();
+                app.calculator.cancel()?;
             }
             Key::Char(c) => {
                 app.calculator.take_input(c)?;