Merge #924

924: Improve show syntax tree r=matklad a=vipentti

This implements some of the features discussed in #820. 

You can now select a range of syntax in a file and then use "Show Syntax Tree" to show its syntax. In addition you can select a range of syntax that is inside a string (typically test cases) and show its syntax as well.

Previous behavior is still available, simply use "Show Syntax Tree" without a selection, and you get the live updating syntax tree. Additionally now the live updating tree will update when the active file is changed. Previously you had to type something in the new file to get the syntax tree to update.

Co-authored-by: Ville Penttinen <[email protected]>

1 files changed, 36 insertions, 10 deletions

diff --git a/editors/code/src/commands/syntaxTree.ts b/editors/code/src/commands/syntaxTree.ts
index c0baf08c5..2f50fe14b 100644
--- a/editors/code/src/commands/syntaxTree.ts
+++ b/editors/code/src/commands/syntaxTree.ts
@@ -1,11 +1,11 @@
 import * as vscode from 'vscode';
-import { TextDocumentIdentifier } from 'vscode-languageclient';
+import { Range, TextDocumentIdentifier } from 'vscode-languageclient';
 
 import { Server } from '../server';
 
 export const syntaxTreeUri = vscode.Uri.parse('rust-analyzer://syntaxtree');
 
-export class TextDocumentContentProvider
+export class SyntaxTreeContentProvider
     implements vscode.TextDocumentContentProvider {
     public eventEmitter = new vscode.EventEmitter<vscode.Uri>();
     public syntaxTree: string = 'Not available';
@@ -17,8 +17,21 @@ export class TextDocumentContentProvider
         if (editor == null) {
             return '';
         }
+
+        let range: Range | undefined;
+
+        // When the range based query is enabled we take the range of the selection
+        if (uri.query === 'range=true') {
+            range = editor.selection.isEmpty
+                ? undefined
+                : Server.client.code2ProtocolConverter.asRange(
+                      editor.selection
+                  );
+        }
+
         const request: SyntaxTreeParams = {
-            textDocument: { uri: editor.document.uri.toString() }
+            textDocument: { uri: editor.document.uri.toString() },
+            range
         };
         return Server.client.sendRequest<SyntaxTreeResult>(
             'rust-analyzer/syntaxTree',
@@ -33,6 +46,7 @@ export class TextDocumentContentProvider
 
 interface SyntaxTreeParams {
     textDocument: TextDocumentIdentifier;
+    range?: Range;
 }
 
 type SyntaxTreeResult = string;
@@ -40,11 +54,23 @@ type SyntaxTreeResult = string;
 // Opens the virtual file that will show the syntax tree
 //
 // The contents of the file come from the `TextDocumentContentProvider`
-export async function handle() {
-    const document = await vscode.workspace.openTextDocument(syntaxTreeUri);
-    return vscode.window.showTextDocument(
-        document,
-        vscode.ViewColumn.Two,
-        true
-    );
+export function createHandle(provider: SyntaxTreeContentProvider) {
+    return async () => {
+        const editor = vscode.window.activeTextEditor;
+        const rangeEnabled = !!(editor && !editor.selection.isEmpty);
+
+        const uri = rangeEnabled
+            ? vscode.Uri.parse(`${syntaxTreeUri.toString()}?range=true`)
+            : syntaxTreeUri;
+
+        const document = await vscode.workspace.openTextDocument(uri);
+
+        provider.eventEmitter.fire(uri);
+
+        return vscode.window.showTextDocument(
+            document,
+            vscode.ViewColumn.Two,
+            true
+        );
+    };
 }