Scripting & Testing

Feature	VS Code	JetBrains	httpyac	VS 2022	kulala
Response handler scripts (> {% %}) httpyac supports for JetBrains compatibility.	✗	✓	✓	✗	✓
Response handler scripts ({{ }}) httpyac-native syntax with full Node.js require() access.	✗	✗	✓	✗	✗
Pre-request scripts (< {% %})	✗	✓	✗	✗	✓
Pre-request scripts ({{ }} before request)	✗	✗	✓	✗	✗
Assertion syntax (?? status == 200) Supports status, header, body, duration, js, xpath assertions.	✗	✗	✓	✗	✗
client.test() API	✗	✓	✓	✗	✓
Crypto API in scripts crypto.hmac.sha256(), crypto.sha256(), etc.	✗	✓	✗	✗	✗
Lua scripting > {% --lua ... %}. Unique to kulala.nvim.	✗	✗	✗	✗	✓
External response handler file (> filepath.js)	✗	✓	✗	✗	✗
Event-specific script hooks {{@request}}, {{@streaming}}, {{@response}}, {{@responseLogging}}, {{@after}}.	✗	✗	✓	✗	✗
Global script registration ({{+...}}) Registers scripts to execute across all requests. {{+after}} runs after every request.	✗	✗	✓	✗	✗
Built-in test helpers (test.status(), test.header()) test.status(), test.totalTime(), test.header(), test.headerContains(), test.responseBody(), etc.	✗	✗	✓	✗	✗

The scripting divide

The most significant split in the .http ecosystem is between clients that support scripting and those that don't:

Limited Support Supported by 2 implementations.

VS Code REST Client and Visual Studio 2022 offer no scripting at all. Response data is accessed only through named request variables (dot-path syntax). There are no assertions, no pre-request logic, no response handlers.

Response handler syntax comparison

The JetBrains response handler syntax has become the de facto standard for scripting — adopted by httpyac (for compatibility) and kulala.nvim.

JetBrains

GET https://api.example.com/users

> {%
client.test("Status is 200", function() {
  client.assert(response.status === 200);
});
client.global.set("count", response.body.length);
%}

httpyac (JetBrains compat)

GET https://api.example.com/users

> {%
client.test("Status is 200", function() {
  client.assert(response.status === 200);
});
%}

httpyac (native)

GET https://api.example.com/users

{{
const { equal } = require('assert');
test('status is 200', () => {
  equal(response.statusCode, 200);
});
}}

httpyac (assertions)

GET https://api.example.com/users

?? status == 200
?? header content-type includes json
?? duration < 500

httpyac additions

httpyac supports JetBrains scripts for compatibility but adds:

• Native double-brace blocks with full Node.js require() access
• ?? assertion syntax for concise, readable tests
• Event hooks for request, streaming, response, and after events

kulala.nvim: Lua scripting

kulala.nvim uniquely supports Lua alongside JavaScript in response handler scripts.

Syntax details: Response Handlers, Pre-Request Scripts.