hjkl movement is now capped to the dimensions of the buffer... sort of

it only checks in the direction of movement, which means it's possible to get outside the text by going up or down off a longer line, onto a shorter one

also, non-printing characters are passed through raw and treated as being exactly one cell wide, and both those things will need to change at some point (try editing a file with color codes in it)

Force-Push: yes
Change-Id: Ie3e82b45a0dba3e52c06c775652d95335242c39b

1 files changed, 14 insertions, 3 deletions

diff --git a/src/main.rs b/src/main.rs
index ea151c8..7f84646 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -185,10 +185,13 @@ impl Ivy {
 
         'j' => {
           self.handle_movement(async |ivy: &mut Ivy| {
+            let buffer = ivy.buffer.read().await;
             let window = ivy.window.write().await;
 
             let mut row = window.cursor_row.write().await;
-            *row += 1;
+            if *row + 1 < buffer.lines.read().await.len() {
+              *row += 1;
+            };
 
             Ok(())
           }).await?;
@@ -209,10 +212,18 @@ impl Ivy {
 
         'l' => {
           self.handle_movement(async |ivy: &mut Ivy| {
+            let buffer = ivy.buffer.read().await;
             let window = ivy.window.write().await;
 
-            let mut column = window.cursor_column.write().await;
-            *column += 1;
+            let row = *window.cursor_row.read().await;
+            if let Some(span) = buffer.line_span(row).await {
+              let width = span.end - span.start;
+
+              let mut column = window.cursor_column.write().await;
+              if *column + 1 < width {
+                *column += 1;
+              }
+            }
 
             Ok(())
           }).await?;