Allow overriding editor settings on a per-language basis

crates/workspace/src/settings.rs

@@ -1,17 +1,33 @@
 use anyhow::Result;
 use gpui::font_cache::{FamilyId, FontCache};
-use postage::watch;
-use std::sync::Arc;
-use theme::{Theme, ThemeRegistry, DEFAULT_THEME_NAME};
+use language::Language;
+use std::{collections::HashMap, sync::Arc};
+use theme::Theme;
 
 #[derive(Clone)]
 pub struct Settings {
     pub buffer_font_family: FamilyId,
     pub buffer_font_size: f32,
     pub tab_size: usize,
+    pub soft_wrap: SoftWrap,
+    pub preferred_line_length: u32,
+    pub overrides: HashMap<String, Override>,
     pub theme: Arc<Theme>,
 }
 
+#[derive(Clone, Default)]
+pub struct Override {
+    pub soft_wrap: Option<SoftWrap>,
+    pub preferred_line_length: Option<u32>,
+}
+
+#[derive(Copy, Clone)]
+pub enum SoftWrap {
+    None,
+    EditorWidth,
+    PreferredLineLength,
+}
+
 impl Settings {
     pub fn new(
         buffer_font_family: &str,
@@ -22,6 +38,9 @@ impl Settings {
             buffer_font_family: font_cache.load_family(&[buffer_font_family])?,
             buffer_font_size: 16.,
             tab_size: 4,
+            soft_wrap: SoftWrap::None,
+            preferred_line_length: 80,
+            overrides: Default::default(),
             theme,
         })
     }
@@ -30,22 +49,23 @@ impl Settings {
         self.tab_size = tab_size;
         self
     }
-}
 
-pub fn channel(
-    buffer_font_family: &str,
-    font_cache: &FontCache,
-    themes: &ThemeRegistry,
-) -> Result<(watch::Sender<Settings>, watch::Receiver<Settings>)> {
-    let theme = match themes.get(DEFAULT_THEME_NAME) {
-        Ok(theme) => theme,
-        Err(err) => {
-            panic!("failed to deserialize default theme: {:?}", err)
-        }
-    };
-    Ok(watch::channel_with(Settings::new(
-        buffer_font_family,
-        font_cache,
-        theme,
-    )?))
+    pub fn with_overrides(mut self, language_name: impl Into<String>, overrides: Override) -> Self {
+        self.overrides.insert(language_name.into(), overrides);
+        self
+    }
+
+    pub fn soft_wrap(&self, language: Option<&Arc<Language>>) -> SoftWrap {
+        language
+            .and_then(|language| self.overrides.get(language.name()))
+            .and_then(|settings| settings.soft_wrap)
+            .unwrap_or(self.soft_wrap)
+    }
+
+    pub fn preferred_line_length(&self, language: Option<&Arc<Language>>) -> u32 {
+        language
+            .and_then(|language| self.overrides.get(language.name()))
+            .and_then(|settings| settings.preferred_line_length)
+            .unwrap_or(self.preferred_line_length)
+    }
 }