squash&merge: Inline diagnostics: helix-editor#6417

book/src/configuration.md

@@ -128,6 +128,7 @@ The following statusline elements can be configured:
 | `display-inlay-hints` | Display inlay hints[^2]                                     | `false` |
 | `display-signature-help-docs` | Display docs under signature help popup             | `true`  |
 | `snippets`      | Enables snippet completions. Requires a server restart (`:lsp-restart`) to take effect after `:config-reload`/`:set`. | `true`  |
+| `display-inline-diagnostics`  | Display diagnostics under their starting line       | `true`  |
 
 [^1]: By default, a progress spinner is shown in the statusline beside the file path.
 [^2]: You may also have to activate them in the LSP config for them to appear, not just in Helix.

book/src/themes.md

@@ -300,6 +300,7 @@ These scopes are used for theming the editor interface:
 | `ui.text.inactive`                | Same as `ui.text` but when the text is inactive (e.g. suggestions)                             |
 | `ui.text.info`                    | The key: command text in `ui.popup.info` boxes                                                 |
 | `ui.virtual.ruler`                | Ruler columns (see the [`editor.rulers` config][editor-section])                               |
+| `ui.virtual.diagnostics`    | Default style for inline diagnostics lines (notably control the background)                    |
 | `ui.virtual.whitespace`           | Visible whitespace characters                                                                  |
 | `ui.virtual.indent-guide`         | Vertical indent width guides                                                                   |
 | `ui.virtual.inlay-hint`           | Default style for inlay hints of all kinds                                                     |

helix-core/src/diagnostic.rs

@@ -1,15 +1,49 @@
 //! LSP diagnostic utility types.
-use serde::{Deserialize, Serialize};
+use serde::de::Error;
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 
 /// Describes the severity level of a [`Diagnostic`].
-#[derive(Debug, Clone, Copy, Eq, PartialEq, PartialOrd, Ord, Deserialize, Serialize)]
+#[derive(Debug, Clone, Copy, Eq, PartialEq, PartialOrd, Ord)]
 pub enum Severity {
     Hint,
     Info,
     Warning,
     Error,
 }
 
+impl Serialize for Severity {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_str(match *self {
+            Severity::Hint => "hint",
+            Severity::Info => "info",
+            Severity::Warning => "warning",
+            Severity::Error => "error",
+        })
+    }
+}
+
+impl<'de> Deserialize<'de> for Severity {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let res = match String::deserialize(deserializer)?.as_str() {
+            "hint" => Severity::Hint,
+            "info" => Severity::Info,
+            "warning" => Severity::Warning,
+            "error" => Severity::Error,
+            _ => {
+                return Err(D::Error::custom(
+                    "expected \"hint\", \"info\", \"warning\" or \"error\"",
+                ))
+            }
+        };
+        Ok(res)
+    }
+}
 impl Default for Severity {
     fn default() -> Self {
         Self::Hint
@@ -23,6 +57,12 @@ pub struct Range {
     pub end: usize,
 }
 
+impl Range {
+    pub fn contains(self, pos: usize) -> bool {
+        (self.start..self.end).contains(&pos)
+    }
+}
+
 #[derive(Debug, Eq, Hash, PartialEq, Clone, Deserialize, Serialize)]
 pub enum NumberOrString {
     Number(i32),
@@ -47,3 +87,9 @@ pub struct Diagnostic {
     pub source: Option<String>,
     pub data: Option<serde_json::Value>,
 }
+
+impl Diagnostic {
+    pub fn severity(&self) -> Severity {
+        self.severity.unwrap_or(Severity::Warning)
+    }
+}