use 'char' type for whitespace substitutions

helix-editor · Mar 15, 2022 · 954d423 · 954d423
1 parent 1010ef2
commit 954d423
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Showing 2 changed files with 16 additions and 27 deletions.
diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
@@ -335,7 +335,7 @@ impl EditorView {
         let mut line = 0u16;
         let tab_width = doc.tab_width();
         let tab = if whitespace.render.tab() == WhitespaceRenderValue::All {
-            (1..tab_width).fold(whitespace.substitutions.tab.clone(), |s, _| s + " ")
+            (1..tab_width).fold(whitespace.substitutions.tab.to_string(), |s, _| s + " ")
         } else {
             " ".repeat(tab_width)
         };
@@ -376,12 +376,16 @@ impl EditorView {
                                     acc.patch(theme.highlight(span.0))
                                 });
 
+                                let char_buf = &mut [0; 4];
+
                                 // we still want to render an empty cell with the style
                                 surface.set_string(
                                     viewport.x + visual_x - offset.col as u16,
                                     viewport.y + line,
                                     if whitespace.render.newline() == WhitespaceRenderValue::All {
-                                        whitespace.substitutions.newline.as_ref()
+                                        let visible_newline: &str =
+                                            whitespace.substitutions.newline.encode_utf8(char_buf);
+                                        visible_newline
                                     } else {
                                         " "
                                     },
@@ -398,6 +402,7 @@ impl EditorView {
                             }
                         } else {
                             let grapheme = Cow::from(grapheme);
+                            let char_buf = &mut [0; 4];
                             let is_whitespace;
 
                             let (grapheme, width) = if grapheme == "\t" {
@@ -414,7 +419,9 @@ impl EditorView {
                             } else if grapheme == " " && should_render_space && !is_trailing_cursor
                             {
                                 is_whitespace = true;
-                                (whitespace.substitutions.space.as_ref(), 1)
+                                let visible_space: &str =
+                                    whitespace.substitutions.space.encode_utf8(char_buf);
+                                (visible_space, 1)
                             } else {
                                 is_whitespace = false;
                                 // Cow will prevent allocations if span contained in a single slice

diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
@@ -296,35 +296,17 @@ impl WhitespaceRender {
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(default)]
 pub struct WhitespaceSubstitutions {
-    #[serde(deserialize_with = "deserialize_single_grapheme")]
-    pub space: String,
-    #[serde(deserialize_with = "deserialize_single_grapheme")]
-    pub tab: String,
-    #[serde(deserialize_with = "deserialize_single_grapheme")]
-    pub newline: String,
-}
-
-fn deserialize_single_grapheme<'de, D>(deserializer: D) -> Result<String, D::Error>
-where
-    D: Deserializer<'de>,
-{
-    let buf = String::deserialize(deserializer)?;
-
-    if helix_core::graphemes::grapheme_width(&buf) == 1 {
-        Ok(buf)
-    } else {
-        Err(serde::de::Error::custom(
-            "whitespace substitions must be single-width graphemes",
-        ))
-    }
+    pub space: char,
+    pub tab: char,
+    pub newline: char,
 }
 
 impl Default for WhitespaceSubstitutions {
     fn default() -> Self {
         Self {
-            space: "·".to_string(),
-            tab: "→".to_string(),
-            newline: "⏎".to_string(),
+            space: '·',
+            tab: '→',
+            newline: '⏎',
         }
     }
 }