Fixes #2122 tools are also found at GOBIN path

src/goInstallTools.ts

@@ -144,9 +144,12 @@ export function installTools(missing: Tool[], goVersion: GoVersion): Promise<voi
 		return;
 	}
 
-	let installingMsg = `Installing ${missing.length} ${missing.length > 1 ? 'tools' : 'tool'} at ${toolsGopath}${
-		path.sep
-	}bin`;
+	let installingMsg = `Installing ${missing.length} ${missing.length > 1 ? 'tools' : 'tool'} at `;
+	if (envForTools['GOBIN']) {
+		installingMsg += `the configured GOBIN: ${envForTools['GOBIN']}`;
+	} else {
+		installingMsg += toolsGopath + path.sep + 'bin';
+	}
 
 	// If the user is on Go >= 1.11, tools should be installed with modules enabled.
 	// This ensures that users get the latest tagged version, rather than master,

src/goPath.ts

@@ -41,6 +41,12 @@ export function getBinPathWithPreferredGopath(toolName: string, preferredGopaths
 	}
 
 	const binname = alternateTool && !path.isAbsolute(alternateTool) ? alternateTool : toolName;
+	const pathFromGoBin = getBinPathFromEnvVar(binname, process.env['GOBIN'], false);
+	if (pathFromGoBin) {
+		binPathCache[toolName] = pathFromGoBin;
+		return pathFromGoBin;
+	}
+
 	for (const preferred of preferredGopaths) {
 		if (typeof preferred === 'string') {
 			// Search in the preferred GOPATH workspace's bin folder