refactor and move lsp types to server boundary (#322)

Author: joshuadavidthomas

Cargo.lock

@@ -0,0 +1,248 @@
+//! LSP client identification for client-specific behavioral overrides.
+
+use djls_source::PositionEncoding;
+use tower_lsp_server::lsp_types;
+
+use crate::ext::ClientInfoExt;
+use crate::ext::PositionEncodingKindExt;
+
+/// LSP client identification for client-specific behavioral overrides.
+///
+/// Most clients work fine with standard LSP behavior, but some require
+/// specific workarounds (e.g., language ID mappings, capability quirks).
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum Client {
+    /// Standard LSP client behavior (no special overrides needed)
+    Default,
+    /// Sublime Text LSP - uses "html" language ID for Django templates
+    SublimeText,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct ClientCapabilities {
+    client: Client,
+    position_encoding: PositionEncoding,
+    pull_diagnostics: bool,
+    snippets: bool,
+}
+
+impl ClientCapabilities {
+    pub fn negotiate(
+        capabilities: &lsp_types::ClientCapabilities,
+        client_info: Option<&lsp_types::ClientInfo>,
+    ) -> Self {
+        let pull_diagnostics = capabilities
+            .text_document
+            .as_ref()
+            .and_then(|text_doc| text_doc.diagnostic.as_ref())
+            .is_some();
+
+        let snippets = capabilities
+            .text_document
+            .as_ref()
+            .and_then(|text_document| text_document.completion.as_ref())
+            .and_then(|completion| completion.completion_item.as_ref())
+            .and_then(|completion_item| completion_item.snippet_support)
+            .unwrap_or(false);
+
+        let client_encodings = capabilities
+            .general
+            .as_ref()
+            .and_then(|general| general.position_encodings.as_ref())
+            .map_or(&[][..], |kinds| kinds.as_slice());
+
+        let position_encoding = [
+            PositionEncoding::Utf8,
+            PositionEncoding::Utf32,
+            PositionEncoding::Utf16,
+        ]
+        .into_iter()
+        .find(|&preferred| {
+            client_encodings
+                .iter()
+                .any(|kind| kind.to_position_encoding() == Some(preferred))
+        })
+        .unwrap_or(PositionEncoding::Utf16);
+
+        let client = client_info.to_client();
+
+        Self {
+            client,
+            position_encoding,
+            pull_diagnostics,
+            snippets,
+        }
+    }
+
+    #[must_use]
+    pub fn position_encoding(self) -> PositionEncoding {
+        self.position_encoding
+    }
+
+    #[must_use]
+    pub fn client(self) -> Client {
+        self.client
+    }
+
+    #[must_use]
+    pub fn supports_pull_diagnostics(self) -> bool {
+        self.pull_diagnostics
+    }
+
+    #[must_use]
+    pub fn supports_snippets(self) -> bool {
+        self.snippets
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::str::FromStr;
+
+    use djls_source::FileKind;
+
+    use super::*;
+    use crate::ext::TextDocumentItemExt;
+
+    #[test]
+    fn test_negotiate_prefers_utf8_when_available() {
+        let capabilities = lsp_types::ClientCapabilities {
+            general: Some(lsp_types::GeneralClientCapabilities {
+                position_encodings: Some(vec![
+                    lsp_types::PositionEncodingKind::new("utf-16"),
+                    lsp_types::PositionEncodingKind::new("utf-8"),
+                    lsp_types::PositionEncodingKind::new("utf-32"),
+                ]),
+                ..Default::default()
+            }),
+            ..Default::default()
+        };
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, None).position_encoding(),
+            PositionEncoding::Utf8
+        );
+    }
+
+    #[test]
+    fn test_negotiate_prefers_utf32_over_utf16() {
+        let capabilities = lsp_types::ClientCapabilities {
+            general: Some(lsp_types::GeneralClientCapabilities {
+                position_encodings: Some(vec![
+                    lsp_types::PositionEncodingKind::new("utf-16"),
+                    lsp_types::PositionEncodingKind::new("utf-32"),
+                ]),
+                ..Default::default()
+            }),
+            ..Default::default()
+        };
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, None).position_encoding(),
+            PositionEncoding::Utf32
+        );
+    }
+
+    #[test]
+    fn test_negotiate_fallback_with_unsupported_encodings() {
+        let capabilities = lsp_types::ClientCapabilities {
+            general: Some(lsp_types::GeneralClientCapabilities {
+                position_encodings: Some(vec![
+                    lsp_types::PositionEncodingKind::new("ascii"),
+                    lsp_types::PositionEncodingKind::new("utf-7"),
+                ]),
+                ..Default::default()
+            }),
+            ..Default::default()
+        };
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, None).position_encoding(),
+            PositionEncoding::Utf16
+        );
+    }
+
+    #[test]
+    fn test_negotiate_fallback_with_no_capabilities() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, None).position_encoding(),
+            PositionEncoding::Utf16
+        );
+    }
+
+    #[test]
+    fn test_negotiate_detects_sublime_client() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        let client_info = lsp_types::ClientInfo {
+            name: "Sublime Text LSP".to_string(),
+            version: Some("1.0.0".to_string()),
+        };
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, Some(&client_info)).client(),
+            Client::SublimeText
+        );
+    }
+
+    #[test]
+    fn test_negotiate_defaults_to_default_client() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        let client_info = lsp_types::ClientInfo {
+            name: "Other Client".to_string(),
+            version: None,
+        };
+        assert_eq!(
+            ClientCapabilities::negotiate(&capabilities, Some(&client_info)).client(),
+            Client::Default
+        );
+    }
+
+    #[test]
+    fn test_map_language_id_sublime_html_to_template() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        let client_info = lsp_types::ClientInfo {
+            name: "Sublime Text LSP".to_string(),
+            version: None,
+        };
+        let client_caps = ClientCapabilities::negotiate(&capabilities, Some(&client_info));
+        let doc = lsp_types::TextDocumentItem {
+            uri: lsp_types::Uri::from_str("file:///test.html").unwrap(),
+            language_id: "html".to_string(),
+            version: 1,
+            text: String::new(),
+        };
+        assert_eq!(
+            doc.language_id_to_file_kind(client_caps.client()),
+            FileKind::Template
+        );
+    }
+
+    #[test]
+    fn test_map_language_id_default_html_to_other() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        let client_caps = ClientCapabilities::negotiate(&capabilities, None);
+        let doc = lsp_types::TextDocumentItem {
+            uri: lsp_types::Uri::from_str("file:///test.html").unwrap(),
+            language_id: "html".to_string(),
+            version: 1,
+            text: String::new(),
+        };
+        assert_eq!(
+            doc.language_id_to_file_kind(client_caps.client()),
+            FileKind::Other
+        );
+    }
+
+    #[test]
+    fn test_map_language_id_django_html_always_template() {
+        let capabilities = lsp_types::ClientCapabilities::default();
+        let client_caps = ClientCapabilities::negotiate(&capabilities, None);
+        let doc = lsp_types::TextDocumentItem {
+            uri: lsp_types::Uri::from_str("file:///test.html").unwrap(),
+            language_id: "django-html".to_string(),
+            version: 1,
+            text: String::new(),
+        };
+        assert_eq!(
+            doc.language_id_to_file_kind(client_caps.client()),
+            FileKind::Template
+        );
+    }
+}