Toggle boolean values using increment/decrement shortcuts

helix-core/src/increment/boolean.rs

@@ -0,0 +1,56 @@
+/// Toggle a boolean value
+pub fn increment(selected_text: &str, _amount: i64) -> Option<String> {
+    match selected_text.trim() {
+        // Common boolean values
+        "true" => Some(String::from("false")),
+        "false" => Some(String::from("true")),
+
+        // Python, Haskell
+        "True" => Some(String::from("False")),
+        "False" => Some(String::from("True")),
+
+        // R, COBOL
+        "TRUE" => Some(String::from("FALSE")),
+        "FALSE" => Some(String::from("TRUE")),
+
+        // Scheme
+        "#t" => Some(String::from("#f")),
+        "#f" => Some(String::from("#t")),
+
+        _ => None,
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_boolean_toggles() {
+        let tests = [
+            // true/false
+            ("true", 1, "false"),
+            ("true", -1, "false"),
+            ("false", 1, "true"),
+            ("false", -1, "true"),
+            // True/False
+            ("True", 1, "False"),
+            ("True", -1, "False"),
+            ("False", 1, "True"),
+            ("False", -1, "True"),
+            // TRUE/FALSE
+            ("TRUE", 1, "FALSE"),
+            ("TRUE", -1, "FALSE"),
+            ("FALSE", 1, "TRUE"),
+            ("FALSE", -1, "TRUE"),
+            // #t/#f
+            ("#t", 1, "#f"),
+            ("#t", -1, "#f"),
+            ("#f", 1, "#t"),
+            ("#f", -1, "#t"),
+        ];
+        for (original, amount, expected) in tests {
+            assert_eq!(increment(original, amount).unwrap(), expected);
+        }
+    }
+}

helix-core/src/increment/mod.rs

@@ -1,5 +1,6 @@
 mod date_time;
 mod integer;
+mod boolean;
 
 pub fn integer(selected_text: &str, amount: i64) -> Option<String> {
     integer::increment(selected_text, amount)
@@ -8,3 +9,7 @@ pub fn integer(selected_text: &str, amount: i64) -> Option<String> {
 pub fn date_time(selected_text: &str, amount: i64) -> Option<String> {
     date_time::increment(selected_text, amount)
 }
+
+pub fn boolean(selected_text: &str, amount: i64) -> Option<String> {
+    boolean::increment(selected_text, amount)
+}

helix-term/src/commands.rs

@@ -6005,7 +6005,7 @@ fn increment_impl(cx: &mut Context, increment_direction: IncrementDirection) {
     for range in selection {
         let selected_text: Cow<str> = range.fragment(text);
         let new_from = ((range.from() as i128) + cumulative_length_diff) as usize;
-        let incremented = [increment::integer, increment::date_time]
+        let incremented = [increment::integer, increment::date_time, increment::boolean]
             .iter()
             .find_map(|incrementor| incrementor(selected_text.as_ref(), amount));