Use DocumentProvider instead of Hover

editors/code/src/commands/expand_macro.ts

@@ -2,47 +2,82 @@ import * as vscode from 'vscode';
 import { Position, TextDocumentIdentifier } from 'vscode-languageclient';
 import { Server } from '../server';
 
-interface ExpandedMacro {
-    name: string,
-    expansion: string,
-}
+export const expandMacroUri = vscode.Uri.parse(
+    'rust-analyzer://expandMacro/[EXPANSION].rs'
+);
 
-function code_format(expanded: ExpandedMacro): vscode.MarkdownString {
-    const markdown = new vscode.MarkdownString(
-        `#### Recursive expansion of ${expanded.name}! macro`
-    );
-    markdown.appendCodeblock(expanded.expansion, 'rust');
-    return markdown;
-}
+export class ExpandMacroContentProvider
+    implements vscode.TextDocumentContentProvider {
+    public eventEmitter = new vscode.EventEmitter<vscode.Uri>();
 
-export class ExpandMacroHoverProvider implements vscode.HoverProvider {
-    public provideHover(
-        document: vscode.TextDocument,
-        position: vscode.Position,
-        token: vscode.CancellationToken
-    ): Thenable<vscode.Hover | null> | null {
+    public provideTextDocumentContent(
+        uri: vscode.Uri
+    ): vscode.ProviderResult<string> {
         async function handle() {
+            const editor = vscode.window.activeTextEditor;
+            if (editor == null) {
+                return '';
+            }
+
+            const position = editor.selection.active;
             const request: MacroExpandParams = {
-                textDocument: { uri: document.uri.toString() },
+                textDocument: { uri: editor.document.uri.toString() },
                 position
             };
-            const result = await Server.client.sendRequest<ExpandedMacro>(
+            const expanded = await Server.client.sendRequest<ExpandedMacro>(
                 'rust-analyzer/expandMacro',
                 request
             );
-            if (result != null) {
-                const formated = code_format(result);
-                return new vscode.Hover(formated);
+
+            if (expanded == null) {
+                return 'Not available';
             }
 
-            return null;
+            return code_format(expanded);
         }
 
         return handle();
     }
+
+    get onDidChange(): vscode.Event<vscode.Uri> {
+        return this.eventEmitter.event;
+    }
+}
+
+// Opens the virtual file that will show the syntax tree
+//
+// The contents of the file come from the `TextDocumentContentProvider`
+export function createHandle(provider: ExpandMacroContentProvider) {
+    return async () => {
+        const uri = expandMacroUri;
+
+        const document = await vscode.workspace.openTextDocument(uri);
+
+        provider.eventEmitter.fire(uri);
+
+        return vscode.window.showTextDocument(
+            document,
+            vscode.ViewColumn.Two,
+            true
+        );
+    };
 }
 
 interface MacroExpandParams {
     textDocument: TextDocumentIdentifier;
     position: Position;
 }
+
+interface ExpandedMacro {
+    name: string;
+    expansion: string;
+}
+
+function code_format(expanded: ExpandedMacro): string {
+    let result = `// Recursive expansion of ${expanded.name}! macro\n`;
+    result += '='.repeat(result.length);
+    result += '\n\n';
+    result += expanded.expansion;
+
+    return result;
+}