Add mouse support to EditView

src/utils/mod.rs

@@ -95,13 +95,20 @@ where
     prefix(iter.rev(), width, delimiter)
 }
 
-/// Computes the length (number of bytes) and width of a suffix that fits in the given `width`.
+/// Computes a suffix that fits in the given `width`.
 ///
 /// Breaks between any two graphemes.
 pub fn simple_suffix(text: &str, width: usize) -> Prefix {
     suffix(text.graphemes(true), width, "")
 }
 
+/// Computes the longest prefix of the given text that fits in the given width.
+///
+/// Breaks between any two graphemes.
+pub fn simple_prefix(text: &str, width: usize) -> Prefix {
+    prefix(text.graphemes(true), width, "")
+}
+
 #[cfg(test)]
 mod tests {
     use utils;

src/views/edit_view.rs

@@ -8,7 +8,7 @@ use std::rc::Rc;
 use theme::{ColorStyle, Effect};
 use unicode_segmentation::UnicodeSegmentation;
 use unicode_width::UnicodeWidthStr;
-use utils::simple_suffix;
+use utils::{simple_prefix, simple_suffix};
 use vec::Vec2;
 use view::View;
 
@@ -571,6 +571,20 @@ impl View for EditView {
                     cb(s, &content);
                 });
             }
+            Event::Mouse {
+                event: MouseEvent::Press(_),
+                position,
+                offset,
+            } if position.fits_in_rect(offset, (self.last_length, 1)) =>
+            {
+                position.checked_sub(offset).map(|position| {
+                    self.cursor = self.offset
+                        + simple_prefix(
+                            &self.content[self.offset..],
+                            position.x,
+                        ).length;
+                });
+            }
             _ => return EventResult::Ignored,
         }