[typescript-language-features] Expandable hover (#228255)

* add verbosity level to hover provider

* cleanup

* update minimum ts version

* get `canIncreaseVerbosityLevel` from server response

* add expandable hover experimental setting

Author: gabritto

extensions/typescript-language-features/package.json

@@ -13,7 +13,8 @@
     "mappedEditsProvider",
     "codeActionAI",
     "codeActionRanges",
-    "documentPaste"
+    "documentPaste",
+    "editorHoverVerbosityLevel"
   ],
   "capabilities": {
     "virtualWorkspaces": {
@@ -825,16 +826,16 @@
           ],
           "enumDescriptions": [
             "%typescript.locale.auto%",
-						"Deutsch",
-						"español",
+            "Deutsch",
+            "español",
             "English",
-						"français",
-						"italiano",
-						"日本語",
-						"한국어",
-						"русский",
-						"中文(简体)",
-						"中文(繁體)"
+            "français",
+            "italiano",
+            "日本語",
+            "한국어",
+            "русский",
+            "中文(简体)",
+            "中文(繁體)"
           ],
           "markdownDescription": "%typescript.locale%",
           "scope": "window"
@@ -1483,14 +1484,27 @@
           "type": "boolean",
           "default": false,
           "description": "%configuration.updateImportsOnPaste%",
-          "tags": ["experimental"]
+          "tags": [
+            "experimental"
+          ]
         },
         "typescript.experimental.updateImportsOnPaste": {
           "scope": "window",
           "type": "boolean",
           "default": false,
           "description": "%configuration.updateImportsOnPaste%",
-          "tags": ["experimental"]
+          "tags": [
+            "experimental"
+          ]
+        },
+        "typescript.experimental.expandableHover": {
+          "type": "boolean",
+          "default": false,
+          "description": "%configuration.expandableHover%",
+          "scope": "window",
+          "tags": [
+            "experimental"
+          ]
         }
       }
     },

extensions/typescript-language-features/package.nls.json

@@ -237,6 +237,7 @@
 	"configuration.tsserver.web.typeAcquisition.enabled": "Enable/disable package acquisition on the web. This enables IntelliSense for imported packages. Requires `#typescript.tsserver.web.projectWideIntellisense.enabled#`. Currently not supported for Safari.",
 	"configuration.tsserver.nodePath": "Run TS Server on a custom Node installation. This can be a path to a Node executable, or 'node' if you want VS Code to detect a Node installation.",
 	"configuration.updateImportsOnPaste": "Automatically update imports when pasting code. Requires TypeScript 5.6+.",
+	"configuration.expandableHover": "(Experimental) Enable/disable expanding on hover.",
 	"walkthroughs.nodejsWelcome.title": "Get started with JavaScript and Node.js",
 	"walkthroughs.nodejsWelcome.description": "Make the most of Visual Studio Code's first-class JavaScript experience.",
 	"walkthroughs.nodejsWelcome.downloadNode.forMacOrWindows.title": "Install Node.js",

extensions/typescript-language-features/src/languageFeatures/hover.ts

@@ -11,10 +11,11 @@ import { DocumentSelector } from '../configuration/documentSelector';
 import { documentationToMarkdown } from './util/textRendering';
 import * as typeConverters from '../typeConverters';
 import FileConfigurationManager from './fileConfigurationManager';
-
+import { API } from '../tsServer/api';
 
 
 class TypeScriptHoverProvider implements vscode.HoverProvider {
+	private lastHoverAndLevel: [vscode.Hover, number] | undefined;
 
 	public constructor(
 		private readonly client: ITypeScriptServiceClient,
@@ -24,27 +25,49 @@ class TypeScriptHoverProvider implements vscode.HoverProvider {
 	public async provideHover(
 		document: vscode.TextDocument,
 		position: vscode.Position,
-		token: vscode.CancellationToken
-	): Promise<vscode.Hover | undefined> {
+		token: vscode.CancellationToken,
+		context?: vscode.HoverContext,
+	): Promise<vscode.VerboseHover | undefined> {
 		const filepath = this.client.toOpenTsFilePath(document);
 		if (!filepath) {
 			return undefined;
 		}
 
+		const enableExpandableHover = vscode.workspace.getConfiguration('typescript').get('experimental.expandableHover');
+		let verbosityLevel: number | undefined;
+		if (enableExpandableHover && this.client.apiVersion.gte(API.v570)) {
+			verbosityLevel = Math.max(0, this.getPreviousLevel(context?.previousHover) + (context?.verbosityDelta ?? 0));
+		}
+		const args = { ...typeConverters.Position.toFileLocationRequestArgs(filepath, position), verbosityLevel };
+
 		const response = await this.client.interruptGetErr(async () => {
 			await this.fileConfigurationManager.ensureConfigurationForDocument(document, token);
 
-			const args = typeConverters.Position.toFileLocationRequestArgs(filepath, position);
 			return this.client.execute('quickinfo', args, token);
 		});
 
 		if (response.type !== 'response' || !response.body) {
 			return undefined;
 		}
 
-		return new vscode.Hover(
-			this.getContents(document.uri, response.body, response._serverType),
-			typeConverters.Range.fromTextSpan(response.body));
+		const contents = this.getContents(document.uri, response.body, response._serverType);
+		const range = typeConverters.Range.fromTextSpan(response.body);
+		const hover = verbosityLevel !== undefined ?
+			new vscode.VerboseHover(
+				contents,
+				range,
+				// @ts-expect-error
+				/*canIncreaseVerbosity*/ response.body.canIncreaseVerbosityLevel,
+				/*canDecreaseVerbosity*/ verbosityLevel !== 0
+			) : new vscode.Hover(
+				contents,
+				range
+			);
+
+		if (verbosityLevel !== undefined) {
+			this.lastHoverAndLevel = [hover, verbosityLevel];
+		}
+		return hover;
 	}
 
 	private getContents(
@@ -72,6 +95,13 @@ class TypeScriptHoverProvider implements vscode.HoverProvider {
 		parts.push(md);
 		return parts;
 	}
+
+	private getPreviousLevel(previousHover: vscode.Hover | undefined): number {
+		if (previousHover && this.lastHoverAndLevel && this.lastHoverAndLevel[0] === previousHover) {
+			return this.lastHoverAndLevel[1];
+		}
+		return 0;
+	}
 }
 
 export function register(

extensions/typescript-language-features/src/tsServer/api.ts

@@ -30,6 +30,7 @@ export class API {
 	public static readonly v540 = API.fromSimpleString('5.4.0');
 	public static readonly v550 = API.fromSimpleString('5.5.0');
 	public static readonly v560 = API.fromSimpleString('5.6.0');
+	public static readonly v570 = API.fromSimpleString('5.7.0');
 
 	public static fromVersionString(versionString: string): API {
 		let version = semver.valid(versionString);

extensions/typescript-language-features/tsconfig.json

@@ -17,5 +17,6 @@
 		"../../src/vscode-dts/vscode.proposed.multiDocumentHighlightProvider.d.ts",
 		"../../src/vscode-dts/vscode.proposed.workspaceTrust.d.ts",
 		"../../src/vscode-dts/vscode.proposed.documentPaste.d.ts",
+		"../../src/vscode-dts/vscode.proposed.editorHoverVerbosityLevel.d.ts",
 	]
 }