Define language settings in the language crate

crates/language/src/language_settings.rs

@@ -0,0 +1,285 @@
+use anyhow::Result;
+use collections::HashMap;
+use gpui::AppContext;
+use schemars::JsonSchema;
+use serde::{Deserialize, Serialize};
+use std::{num::NonZeroU32, path::Path, sync::Arc};
+
+pub fn init(cx: &mut AppContext) {
+    settings::register_setting::<AllLanguageSettings>(cx);
+}
+
+pub fn language_settings<'a>(
+    path: Option<&Path>,
+    language: Option<&str>,
+    cx: &'a AppContext,
+) -> &'a LanguageSettings {
+    settings::get_setting::<AllLanguageSettings>(path, cx).language(language)
+}
+
+pub fn all_language_settings<'a>(
+    path: Option<&Path>,
+    cx: &'a AppContext,
+) -> &'a AllLanguageSettings {
+    settings::get_setting::<AllLanguageSettings>(path, cx)
+}
+
+#[derive(Debug, Clone)]
+pub struct AllLanguageSettings {
+    pub copilot: CopilotSettings,
+    defaults: LanguageSettings,
+    languages: HashMap<Arc<str>, LanguageSettings>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct LanguageSettings {
+    pub tab_size: NonZeroU32,
+    pub hard_tabs: bool,
+    pub soft_wrap: SoftWrap,
+    pub preferred_line_length: u32,
+    pub format_on_save: FormatOnSave,
+    pub remove_trailing_whitespace_on_save: bool,
+    pub ensure_final_newline_on_save: bool,
+    pub formatter: Formatter,
+    pub enable_language_server: bool,
+    pub show_copilot_suggestions: bool,
+    pub show_whitespaces: ShowWhitespaceSetting,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct CopilotSettings {
+    pub feature_enabled: bool,
+    pub disabled_globs: Vec<glob::Pattern>,
+}
+
+#[derive(Clone, Serialize, Deserialize, JsonSchema)]
+pub struct AllLanguageSettingsContent {
+    #[serde(default)]
+    pub features: Option<FeaturesContent>,
+    #[serde(default)]
+    pub copilot: Option<CopilotSettingsContent>,
+    #[serde(flatten)]
+    pub defaults: LanguageSettingsContent,
+    #[serde(default, alias = "language_overrides")]
+    pub languages: HashMap<Arc<str>, LanguageSettingsContent>,
+}
+
+#[derive(Clone, Default, Serialize, Deserialize, JsonSchema)]
+pub struct LanguageSettingsContent {
+    #[serde(default)]
+    pub tab_size: Option<NonZeroU32>,
+    #[serde(default)]
+    pub hard_tabs: Option<bool>,
+    #[serde(default)]
+    pub soft_wrap: Option<SoftWrap>,
+    #[serde(default)]
+    pub preferred_line_length: Option<u32>,
+    #[serde(default)]
+    pub format_on_save: Option<FormatOnSave>,
+    #[serde(default)]
+    pub remove_trailing_whitespace_on_save: Option<bool>,
+    #[serde(default)]
+    pub ensure_final_newline_on_save: Option<bool>,
+    #[serde(default)]
+    pub formatter: Option<Formatter>,
+    #[serde(default)]
+    pub enable_language_server: Option<bool>,
+    #[serde(default)]
+    pub show_copilot_suggestions: Option<bool>,
+    #[serde(default)]
+    pub show_whitespaces: Option<ShowWhitespaceSetting>,
+}
+
+#[derive(Clone, Debug, Default, Serialize, Deserialize, JsonSchema)]
+pub struct CopilotSettingsContent {
+    #[serde(default)]
+    pub disabled_globs: Option<Vec<String>>,
+}
+
+#[derive(Clone, Default, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub struct FeaturesContent {
+    pub copilot: Option<bool>,
+}
+
+#[derive(Copy, Clone, Debug, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum SoftWrap {
+    None,
+    EditorWidth,
+    PreferredLineLength,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum FormatOnSave {
+    On,
+    Off,
+    LanguageServer,
+    External {
+        command: Arc<str>,
+        arguments: Arc<[String]>,
+    },
+}
+
+#[derive(Copy, Clone, Debug, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum ShowWhitespaceSetting {
+    Selection,
+    None,
+    All,
+}
+
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum Formatter {
+    LanguageServer,
+    External {
+        command: Arc<str>,
+        arguments: Arc<[String]>,
+    },
+}
+
+impl AllLanguageSettings {
+    pub fn language<'a>(&'a self, language_name: Option<&str>) -> &'a LanguageSettings {
+        if let Some(name) = language_name {
+            if let Some(overrides) = self.languages.get(name) {
+                return overrides;
+            }
+        }
+        &self.defaults
+    }
+
+    pub fn copilot_enabled_for_path(&self, path: &Path) -> bool {
+        !self
+            .copilot
+            .disabled_globs
+            .iter()
+            .any(|glob| glob.matches_path(path))
+    }
+
+    pub fn copilot_enabled(&self, language_name: Option<&str>, path: Option<&Path>) -> bool {
+        if !self.copilot.feature_enabled {
+            return false;
+        }
+
+        if let Some(path) = path {
+            if !self.copilot_enabled_for_path(path) {
+                return false;
+            }
+        }
+
+        self.language(language_name).show_copilot_suggestions
+    }
+}
+
+impl settings::Setting for AllLanguageSettings {
+    const KEY: Option<&'static str> = None;
+
+    type FileContent = AllLanguageSettingsContent;
+
+    fn load(
+        default_value: &Self::FileContent,
+        user_settings: &[&Self::FileContent],
+        _: &AppContext,
+    ) -> Result<Self> {
+        // A default is provided for all settings.
+        let mut defaults: LanguageSettings =
+            serde_json::from_value(serde_json::to_value(&default_value.defaults)?)?;
+
+        let mut languages = HashMap::default();
+        for (language_name, settings) in &default_value.languages {
+            let mut language_settings = defaults.clone();
+            merge_settings(&mut language_settings, &settings);
+            languages.insert(language_name.clone(), language_settings);
+        }
+
+        let mut copilot_enabled = default_value
+            .features
+            .as_ref()
+            .and_then(|f| f.copilot)
+            .ok_or_else(Self::missing_default)?;
+        let mut copilot_globs = default_value
+            .copilot
+            .as_ref()
+            .and_then(|c| c.disabled_globs.as_ref())
+            .ok_or_else(Self::missing_default)?;
+
+        for user_settings in user_settings {
+            if let Some(copilot) = user_settings.features.as_ref().and_then(|f| f.copilot) {
+                copilot_enabled = copilot;
+            }
+            if let Some(globs) = user_settings
+                .copilot
+                .as_ref()
+                .and_then(|f| f.disabled_globs.as_ref())
+            {
+                copilot_globs = globs;
+            }
+
+            // A user's global settings override the default global settings and
+            // all default language-specific settings.
+            merge_settings(&mut defaults, &user_settings.defaults);
+            for language_settings in languages.values_mut() {
+                merge_settings(language_settings, &user_settings.defaults);
+            }
+
+            // A user's language-specific settings override default language-specific settings.
+            for (language_name, user_language_settings) in &user_settings.languages {
+                merge_settings(
+                    languages
+                        .entry(language_name.clone())
+                        .or_insert_with(|| defaults.clone()),
+                    &user_language_settings,
+                );
+            }
+        }
+
+        Ok(Self {
+            copilot: CopilotSettings {
+                feature_enabled: copilot_enabled,
+                disabled_globs: copilot_globs
+                    .iter()
+                    .filter_map(|pattern| glob::Pattern::new(pattern).ok())
+                    .collect(),
+            },
+            defaults,
+            languages,
+        })
+    }
+}
+
+fn merge_settings(settings: &mut LanguageSettings, src: &LanguageSettingsContent) {
+    merge(&mut settings.tab_size, src.tab_size);
+    merge(&mut settings.hard_tabs, src.hard_tabs);
+    merge(&mut settings.soft_wrap, src.soft_wrap);
+    merge(
+        &mut settings.preferred_line_length,
+        src.preferred_line_length,
+    );
+    merge(&mut settings.formatter, src.formatter.clone());
+    merge(&mut settings.format_on_save, src.format_on_save.clone());
+    merge(
+        &mut settings.remove_trailing_whitespace_on_save,
+        src.remove_trailing_whitespace_on_save,
+    );
+    merge(
+        &mut settings.ensure_final_newline_on_save,
+        src.ensure_final_newline_on_save,
+    );
+    merge(
+        &mut settings.enable_language_server,
+        src.enable_language_server,
+    );
+    merge(
+        &mut settings.show_copilot_suggestions,
+        src.show_copilot_suggestions,
+    );
+    merge(&mut settings.show_whitespaces, src.show_whitespaces);
+
+    fn merge<T>(target: &mut T, value: Option<T>) {
+        if let Some(value) = value {
+            *target = value;
+        }
+    }
+}