A toolkit for test case and test data creation

npm install @xhubio/nanook-table

# Node.js >= 22. One ESM package, types included.
# Everything is imported from that one module:
#   TestcaseProcessor, FileProcessor, ImporterXlsx,
#   ParserDecision, ParserMatrix, ParserSpecification,
#   DataGeneratorRegistry, DataGeneratorBase,
#   GeneratorFaker, LoggerMemory, TableDecision,
#   TableMatrix, …

From the README of @xhubio/nanook-table 3.0.1.

$ claude
> /createEquivalenceClassTable Login Form

  17.5 minutes, 56 turns, no further input

  resources/login-form-tests.xlsx
    User   7 columns, 15 combinations, 100 %
    Login  7 columns, 48 combinations, 100 %
  scripts/create-login-form-table.ts
  scripts/check-login-form-table.ts
  scripts/generate-login-form-fixtures.ts

$ node scripts/generate-login-form-fixtures.ts
  11 fixtures written to fixtures/login-form

Summary of the run behind the Quickstart with Claude Code (2 September 2026). The skill has shipped with the package since 2.1.0.

import {
  LoggerMemory, FileProcessor, ImporterXlsx,
  ParserDecision, DataGeneratorRegistry, GeneratorFaker,
  TestcaseProcessor, type InterfaceWriter
} from '@xhubio/nanook-table'

const logger = new LoggerMemory()
logger.writeConsole = true

const fileProcessor = new FileProcessor({ logger })
fileProcessor.registerImporter(
  'xlsx',
  new ImporterXlsx()
)
fileProcessor.registerParser(
  '<DECISION_TABLE>',
  new ParserDecision({ logger })
)
await fileProcessor.load(['resources/login.xlsx'])

const registry = new DataGeneratorRegistry()
registry.registerGenerator(
  'faker',
  new GeneratorFaker({ logger })
)

const collected: unknown[] = []
const writer: InterfaceWriter = {
  logger,
  async before() {},
  async write(tc) {
    collected.push(JSON.parse(JSON.stringify(tc)))
  },
  async after() {},
}

const tables = Object.fromEntries(
  fileProcessor.tables.map((t) => [t.tableName, t])
)

const processor = new TestcaseProcessor({
  logger,
  tables,
  generatorRegistry: registry,
  writer: [writer],
})
await processor.process()

console.log(JSON.stringify(collected[0], null, 2))

Adapted from the script that generated the login example for the blog: package imports instead of source imports and without its custom len generator, otherwise the same calls. Runs on @xhubio/nanook-table 3.0.1.

{
  "tableName": "Login",
  "name": "OK_login",
  "data": {
    "Login": {
      "4679e9a0-6d2d-4fea-8351-9677ed8573b6": {
        "account": "active",
        "Expected reaction": [
          {
            "key": "signed in",
            "comment": "session cookie is set"
          }
        ],
        "Expected effect": [
          {
            "key": "failed-attempt counter unchanged",
            "comment": "success or unknown user"
          }
        ],
        "email": "Jennifer_Tremblay@hotmail.com",
        "password": "VuZGJBushpsbY_b"
      }
    }
  },
  "instanceId": "4679e9a0-6d2d-4fea-8351-9677ed8573b6",
  "callTree": {
    "instanceId": "218e4109-1b41-4269-8cac-d10c92551e39",
    "tableName": "Login",
    "testcaseName": "OK_login",
    "neverExecute": false,
    "tags": [],
    "children": []
  },
  "postProcessDirectives": []
}

What the script prints: the first test case of that run, e-mail and password from the Faker generator. Nanook's default writer would store each one as tdg/<name>/testcaseData.json.