feat: add k indices to title pattern, closes #4

README.md

@@ -59,6 +59,33 @@ it.each(data)('element %s should %s', (selector, assertion) => {
 // "element .new-todo should not.be.visible"
 ```
 
+## Test and suite titles
+
+You can use the arguments to the test callback in the test title in order.
+
+```js
+it.each([10, 20, 30])('number is %d', (x) => { ... })
+// creates the tests
+// "number is 10"
+// "number is 20"
+// "number is 30"
+```
+
+If you want to use the iteration variable in the title, use `%k` for zero-based index, or `%K` for one-based index.
+
+```js
+it.each([10, 20, 30])('checking item %k', (x) => { ... })
+// creates the tests
+// "checking item 0"
+// "checking item 1"
+// "checking item 2"
+it.each([10, 20, 30])('checking item %K', (x) => { ... })
+// creates the tests
+// "checking item 1"
+// "checking item 2"
+// "checking item 3"
+```
+
 ## Examples
 
 - Watch [Using cypress-each To Create Separate Tests](https://youtu.be/utPKRV_fL1E)

cypress/integration/each-k.js

@@ -0,0 +1,20 @@
+// @ts-check
+/// <reference types="cypress" />
+
+import '../..'
+
+it('has test title', function () {
+  expect(this, 'has test').to.have.property('test')
+  // @ts-ignore
+  expect(this.test.title).to.equal('has test title')
+})
+
+it.each([1, 2, 3])('has 0-based index %k', function (x) {
+  expect(x).to.be.oneOf([1, 2, 3])
+  // needs test context to be passed correctly by it.each
+  // expect(this.test.title).to.equal('has 0-based index 0')
+})
+
+it.each([1, 2, 3])('has 1-based index %K', (x) => {
+  expect(x).to.be.oneOf([1, 2, 3])
+})

cypress/integration/format-spec.js

@@ -1,13 +1,20 @@
 // @ts-check
 /// <reference types="cypress" />
 
-import '../..'
+// @ts-ignore
+require('../..')
+// @ts-ignore
+const { formatTitle } = require('../../src/index.js')
 
 describe('format', () => {
   const person = {
     name: 'Joe',
   }
 
+  it('formats title using %d', () => {
+    expect(formatTitle('one is %d', 1)).to.equal('one is 1')
+  })
+
   // it should only use the number of arguments
   // in the string format, and not all available arguments
   it.each([['person', person, 42]])('I am a %s', (name, who, life) => {

src/index.js

@@ -14,13 +14,15 @@ function formatTitle(pattern, ...values) {
 if (!it.each) {
   it.each = (values) => {
     return function (titlePattern, testCallback) {
-      values.forEach((value) => {
+      values.forEach((value, k) => {
+        const testTitle = titlePattern.replace('%k', k).replace('%K', k + 1)
+
         // define a test for each value
         if (Array.isArray(value)) {
-          const title = formatTitle(titlePattern, ...value)
+          const title = formatTitle(testTitle, ...value)
           it(title, testCallback.bind(null, ...value))
         } else {
-          const title = formatTitle(titlePattern, value)
+          const title = formatTitle(testTitle, value)
           it(title, testCallback.bind(null, value))
         }
       })
@@ -32,15 +34,19 @@ if (!describe.each) {
   describe.each = (values) => {
     return function describeEach(titlePattern, testCallback) {
       // define a test for each value
-      values.forEach((value) => {
+      values.forEach((value, k) => {
+        const testTitle = titlePattern.replace('%k', k).replace('%K', k + 1)
+
         if (Array.isArray(value)) {
-          const title = formatTitle(titlePattern, ...value)
+          const title = formatTitle(testTitle, ...value)
           describe(title, testCallback.bind(null, ...value))
         } else {
-          const title = formatTitle(titlePattern, value)
+          const title = formatTitle(testTitle, value)
           describe(title, testCallback.bind(null, value))
         }
       })
     }
   }
 }
+
+module.exports = { formatTitle }