Impl displaying signature from LSP (lapce#1720)

Author: MinusGix

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 ### Features/Changes
+- [#1720](https://github.com/lapce/lapce/pull/1720): Display signature/parameter information from LSP
 
 ### Bug Fixes
 

defaults/keymaps-macos.toml

@@ -200,6 +200,11 @@ key = "meta+i"
 command = "get_completion"
 mode = "i"
 
+[[keymaps]]
+key = "ctrl+shift+space"
+command = "get_signature"
+mode = "i"
+
 [[keymaps]]
 key = "meta+."
 command = "show_code_actions"

defaults/keymaps-nonmacos.toml

@@ -218,6 +218,11 @@ key = "ctrl+i"
 command = "get_completion"
 mode = "i"
 
+[[keymaps]]
+key = "ctrl+shift+space"
+command = "get_signature"
+mode = "i"
+
 [[keymaps]]
 key = "ctrl+."
 command = "show_code_actions"

defaults/settings.toml

@@ -18,6 +18,8 @@ scroll-beyond-last-line = true
 cursor-surrounding-lines = 1
 sticky-header = true
 completion-show-documentation = true
+show-signature = true
+signature-label-code-block = true
 auto-closing-matching-pairs = true
 hover-delay = 300                       # ms
 modal-mode-relative-line-numbers = true

lapce-core/src/command.rs

@@ -257,6 +257,8 @@ pub enum FocusCommand {
     ShowCodeActions,
     #[strum(serialize = "get_completion")]
     GetCompletion,
+    #[strum(serialize = "get_signature")]
+    GetSignature,
     /// This will close a modal, such as the settings window or completion
     #[strum(message = "Close Modal")]
     #[strum(serialize = "modal.close")]

lapce-data/src/command.rs

@@ -25,7 +25,8 @@ use lapce_xi_rope::{spans::Spans, Rope};
 use lsp_types::{
     CodeActionOrCommand, CodeActionResponse, CompletionItem, CompletionResponse,
     InlayHint, Location, MessageType, Position, ProgressParams,
-    PublishDiagnosticsParams, SelectionRange, TextEdit, WorkspaceEdit,
+    PublishDiagnosticsParams, SelectionRange, SignatureHelp, TextEdit,
+    WorkspaceEdit,
 };
 use serde_json::Value;
 use strum::{self, EnumMessage, IntoEnumIterator};
@@ -560,6 +561,11 @@ pub enum LapceUICommand {
     CancelCompletion(usize),
     ResolveCompletion(BufferId, u64, usize, Box<CompletionItem>),
     UpdateCompletion(usize, String, CompletionResponse, PluginId),
+    UpdateSignature {
+        request_id: usize,
+        resp: SignatureHelp,
+        plugin_id: PluginId,
+    },
     UpdateHover(usize, Arc<Vec<RichText>>),
     UpdateVoltReadme(RichText),
     UpdateInlayHints {

lapce-data/src/config.rs

@@ -340,6 +340,14 @@ pub struct EditorConfig {
         desc = "If the editor should show the documentation of the current completion item"
     )]
     pub completion_show_documentation: bool,
+    #[field_names(
+        desc = "If the editor should show the signature of the function as the parameters are being typed"
+    )]
+    pub show_signature: bool,
+    #[field_names(
+        desc = "If the signature view should put the codeblock into a label. This might not work nicely for LSPs which provide invalid code for their labels."
+    )]
+    pub signature_label_code_block: bool,
     #[field_names(
         desc = "Whether the editor should disable automatic closing of matching pairs"
     )]

lapce-data/src/data.rs

@@ -76,6 +76,7 @@ use crate::{
     rename::RenameData,
     search::SearchData,
     settings::LapceSettingsPanelData,
+    signature::SignatureData,
     source_control::SourceControlData,
     split::{SplitDirection, SplitMoveDirection},
     terminal::TerminalSplitData,
@@ -626,6 +627,7 @@ pub struct LapceTabData {
     pub title: Arc<TitleData>,
     pub main_split: LapceMainSplitData,
     pub completion: Arc<CompletionData>,
+    pub signature: Arc<SignatureData>,
     pub hover: Arc<HoverData>,
     pub rename: Arc<RenameData>,
     pub terminal: Arc<TerminalSplitData>,
@@ -721,6 +723,7 @@ impl LapceTabData {
         let palette = Arc::new(PaletteData::new(config.clone(), proxy.clone()));
         let completion = Arc::new(CompletionData::new(config.clone()));
         let hover = Arc::new(HoverData::new());
+        let signature = Arc::new(SignatureData::new());
         let rename = Arc::new(RenameData::new());
         let source_control = Arc::new(SourceControlData::new());
         let settings = Arc::new(LapceSettingsPanelData::new());
@@ -840,6 +843,7 @@ impl LapceTabData {
             title,
             main_split,
             completion,
+            signature,
             hover,
             rename,
             terminal,
@@ -937,6 +941,7 @@ impl LapceTabData {
             view_id: editor_view_id,
             main_split: self.main_split.clone(),
             completion: self.completion.clone(),
+            signature: self.signature.clone(),
             hover: self.hover.clone(),
             rename: self.rename.clone(),
             focus_area: self.focus_area.clone(),
@@ -985,6 +990,7 @@ impl LapceTabData {
         doc: &Arc<Document>,
     ) {
         self.completion = editor_buffer_data.completion.clone();
+        self.signature = editor_buffer_data.signature.clone();
         self.hover = editor_buffer_data.hover.clone();
         self.rename = editor_buffer_data.rename.clone();
         self.main_split = editor_buffer_data.main_split.clone();
@@ -1074,6 +1080,50 @@ impl LapceTabData {
         }
     }
 
+    pub fn signature_origin(
+        &self,
+        text: &mut PietText,
+        tab_size: Size,
+        signature_size: Size,
+        config: &LapceConfig,
+    ) -> Point {
+        let editor = self.main_split.active_editor();
+        let editor = match editor {
+            Some(editor) => editor,
+            None => return Point::ZERO,
+        };
+
+        match &editor.content {
+            BufferContent::File(_) | BufferContent::Scratch(_, _) => {
+                let doc = self.main_split.editor_doc(editor.view_id);
+                let offset = self.signature.offset;
+                let (point_above, _point_below) =
+                    doc.points_of_offset(text, offset, &editor.view, config);
+
+                let mut origin = *editor.window_origin.borrow()
+                    - self.window_origin.borrow().to_vec2()
+                    + Vec2::new(point_above.x - 5.0, point_above.y)
+                    - Vec2::new(0.0, signature_size.height);
+
+                // TODO: What about if the signature's position is past the tab size?
+
+                if origin.x + signature_size.width + 1.0 > tab_size.width {
+                    origin.x = tab_size.width - signature_size.width - 1.0;
+                }
+
+                if origin.x <= 0.0 {
+                    origin.x = 0.0;
+                }
+
+                origin
+            }
+            BufferContent::SettingsValue(_) | BufferContent::Local(_) => {
+                *editor.window_origin.borrow()
+                    - self.window_origin.borrow().to_vec2()
+            }
+        }
+    }
+
     pub fn rename_origin(
         &self,
         text: &mut PietText,

lapce-data/src/editor.rs

@@ -55,6 +55,7 @@ use crate::{
     proxy::{path_from_url, LapceProxy},
     rename::RenameData,
     selection_range::SelectionRangeDirection,
+    signature::{SignatureData, SignatureStatus},
     source_control::SourceControlData,
     split::{SplitDirection, SplitMoveDirection},
 };
@@ -208,6 +209,7 @@ pub struct LapceEditorBufferData {
     pub editor: Arc<LapceEditorData>,
     pub doc: Arc<Document>,
     pub completion: Arc<CompletionData>,
+    pub signature: Arc<SignatureData>,
     pub hover: Arc<HoverData>,
     pub rename: Arc<RenameData>,
     pub main_split: LapceMainSplitData,
@@ -341,6 +343,12 @@ impl LapceEditorBufferData {
             && self.completion.len() > 0
     }
 
+    /// Check if there are signatures that are being rendered
+    fn has_signature(&self) -> bool {
+        self.signature.status != SignatureStatus::Inactive
+            && !self.signature.is_empty()
+    }
+
     fn has_hover(&self) -> bool {
         self.hover.status != HoverStatus::Inactive && !self.hover.is_empty()
     }
@@ -612,6 +620,14 @@ impl LapceEditorBufferData {
         completion.cancel();
     }
 
+    pub fn cancel_signature(&mut self) {
+        if self.signature.status == SignatureStatus::Inactive {
+            return;
+        }
+        let signature = Arc::make_mut(&mut self.signature);
+        signature.cancel();
+    }
+
     pub fn cancel_hover(&mut self) {
         let hover = Arc::make_mut(&mut self.hover);
         hover.cancel();
@@ -781,6 +797,34 @@ impl LapceEditorBufferData {
         }
     }
 
+    fn update_signature(&mut self) {
+        if self.get_mode() != Mode::Insert {
+            self.cancel_signature();
+            return;
+        }
+        if !self.doc.loaded() || !self.doc.content().is_file() {
+            return;
+        }
+
+        let offset = self.editor.cursor.offset();
+        let start_offset = self.doc.buffer().prev_code_boundary(offset);
+
+        let signature = Arc::make_mut(&mut self.signature);
+
+        signature.buffer_id = self.doc.id();
+        signature.offset = start_offset;
+        signature.status = SignatureStatus::Started;
+        signature.request_id += 1;
+
+        let start_pos = self.doc.buffer().offset_to_position(start_offset);
+        signature.request(
+            self.proxy.clone(),
+            signature.request_id,
+            self.doc.content().path().unwrap().into(),
+            start_pos,
+        );
+    }
+
     /// return true if there's existing hover and it's not changed
     pub fn check_hover(
         &mut self,
@@ -1416,6 +1460,10 @@ impl LapceEditorBufferData {
             }
         }
         self.cancel_completion();
+        // Cancel but then immediately try to see if there's a signature to provide
+        // TODO: Can we be smarter about this?
+        self.cancel_signature();
+        self.update_signature();
         self.cancel_hover();
         CommandExecuted::Yes
     }
@@ -1447,8 +1495,11 @@ impl LapceEditorBufferData {
 
         if show_completion(cmd, &doc_before_edit, &deltas) {
             self.update_completion(ctx, false);
+            // TODO: This can be requested in more specific cases based on the LSP supplied trigger
+            self.update_signature();
         } else {
             self.cancel_completion();
+            self.cancel_signature();
         }
         self.apply_deltas(&deltas);
 
@@ -1478,6 +1529,9 @@ impl LapceEditorBufferData {
                 if self.has_completions() {
                     self.cancel_completion();
                 }
+                if self.has_signature() {
+                    self.cancel_signature();
+                }
                 if self.has_hover() {
                     self.cancel_hover();
                 }
@@ -1822,6 +1876,7 @@ impl LapceEditorBufferData {
                     if last_placeholder {
                         Arc::make_mut(&mut self.editor).snippet = None;
                     }
+                    self.update_signature();
                     self.cancel_completion();
                 }
             }
@@ -1848,6 +1903,7 @@ impl LapceEditorBufferData {
                                 .cursor
                                 .set_insert(selection);
                         }
+                        self.update_signature();
                         self.cancel_completion();
                     }
                 }
@@ -1902,6 +1958,9 @@ impl LapceEditorBufferData {
                 // we allow empty inputs to allow for cases where the user wants to get the autocompletion beforehand
                 self.update_completion(ctx, true);
             }
+            GetSignature => {
+                self.update_signature();
+            }
             GotoDefinition => {
                 if let BufferContent::File(path) = self.doc.content() {
                     let offset = self.editor.cursor.offset();
@@ -2392,6 +2451,7 @@ impl LapceEditorBufferData {
         let cursor = &mut Arc::make_mut(&mut self.editor).cursor;
         self.doc
             .do_multi_selection(ctx.text(), cursor, cmd, &view, &self.config);
+        self.cancel_signature();
         self.cancel_completion();
         CommandExecuted::Yes
     }
@@ -2465,6 +2525,7 @@ impl KeyPressFocus for LapceEditorBufferData {
                 .all(|c| c.is_whitespace() || c.is_ascii_whitespace())
             {
                 self.update_completion(ctx, false);
+                self.update_signature();
             } else {
                 self.cancel_completion();
             }