Go to Type definition implementation

src/goMain.ts

@@ -46,6 +46,7 @@ import { buildCode } from './goBuild';
 import { installCurrentPackage } from './goInstall';
 import { updateWorkspaceModCache } from './goModules';
 import { setGlobalState } from './stateUtils';
+import { GoTypeDefinitionProvider } from './goTypeDefinition';
 
 export let buildDiagnosticCollection: vscode.DiagnosticCollection;
 export let lintDiagnosticCollection: vscode.DiagnosticCollection;
@@ -158,6 +159,7 @@ export function activate(ctx: vscode.ExtensionContext): void {
 			registerCompletionProvider(ctx);
 			ctx.subscriptions.push(vscode.languages.registerHoverProvider(GO_MODE, new GoHoverProvider()));
 			ctx.subscriptions.push(vscode.languages.registerDefinitionProvider(GO_MODE, new GoDefinitionProvider()));
+			ctx.subscriptions.push(vscode.languages.registerTypeDefinitionProvider(GO_MODE, new GoTypeDefinitionProvider()));
 			ctx.subscriptions.push(vscode.languages.registerReferenceProvider(GO_MODE, new GoReferenceProvider()));
 			ctx.subscriptions.push(vscode.languages.registerDocumentSymbolProvider(GO_MODE, new GoDocumentSymbolProvider()));
 			ctx.subscriptions.push(vscode.languages.registerWorkspaceSymbolProvider(new GoWorkspaceSymbolProvider()));

src/goTypeDefinition.ts

@@ -0,0 +1,93 @@
+/*---------------------------------------------------------
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------*/
+
+'use strict';
+
+import vscode = require('vscode');
+import cp = require('child_process');
+import path = require('path');
+import { byteOffsetAt, getBinPath, canonicalizeGOPATHPrefix, getFileArchive, killTree } from './util';
+import { promptForMissingTool } from './goInstallTools';
+import { getToolsEnvVars } from './util';
+
+interface GuruDescribeOutput {
+	desc: string;
+	pos: string;
+	detail: string;
+	value: GuruDescribeValueOutput;
+}
+
+interface GuruDescribeValueOutput {
+	type: string;
+	value: string;
+	objpos: string;
+	typespos: GuruDefinitionOutput[];
+}
+
+interface GuruDefinitionOutput {
+	objpos: string;
+	desc: string;
+}
+
+export class GoTypeDefinitionProvider implements vscode.TypeDefinitionProvider {
+	provideTypeDefinition(document: vscode.TextDocument, position: vscode.Position, token: vscode.CancellationToken): vscode.ProviderResult<vscode.Definition> {
+		return new Promise<vscode.Location[]>((resolve, reject) => {
+			let goGuru = getBinPath('guru');
+			if (!path.isAbsolute(goGuru)) {
+				promptForMissingTool('guru');
+				return reject('Cannot find tool "guru" to find references.');
+			}
+
+			let filename = canonicalizeGOPATHPrefix(document.fileName);
+			let cwd = path.dirname(filename);
+			let offset = byteOffsetAt(document, position);
+			let env = getToolsEnvVars();
+			let buildTags = vscode.workspace.getConfiguration('go', document.uri)['buildTags'];
+			let args = buildTags ? ['-tags', buildTags] : [];
+			args.push('-json', '-modified', 'describe', `${filename}:#${offset.toString()}`);
+
+			let process = cp.execFile(goGuru, args, { env }, (err, stdout, stderr) => {
+				try {
+					if (err && (<any>err).code === 'ENOENT') {
+						promptForMissingTool('guru');
+						return resolve(null);
+					}
+
+					if (err) {
+						return reject(err);
+					}
+
+					let guruOutput = <GuruDescribeOutput>JSON.parse(stdout.toString());
+					let results: vscode.Location[] = [];
+
+					if (!guruOutput.value || !guruOutput.value.typespos) {
+						return resolve(null);
+					}
+
+					guruOutput.value.typespos.forEach(ref => {
+						let match = /^(.*):(\d+):(\d+)/.exec(ref.objpos);
+						if (!match) return;
+						let [_, file, lineStartStr, colStartStr] = match;
+						let referenceResource = vscode.Uri.file(path.resolve(cwd, file));
+						let range = new vscode.Range(
+							+lineStartStr - 1, +colStartStr - 1, +lineStartStr - 1, +colStartStr
+						);
+						results.push(new vscode.Location(referenceResource, range));
+					});
+
+					resolve(results);
+				} catch (e) {
+					reject(e);
+				}
+			});
+			if (process.pid) {
+				process.stdin.end(getFileArchive(document));
+			}
+			token.onCancellationRequested(() =>
+				killTree(process.pid)
+			);
+		});
+	}
+}