fix(TS): fix types and add tests for types (#21)

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<!-- What changes are being made? (What feature/bug is being fixed here?) -->

**What**: 
- fixed TypeScript types
- added jsdoc for helpers
- added tests for types

<!-- Why are these changes necessary? -->

**Why**: types were not working
reported here #18 (comment) by @aaronmcadam and @freddydumont

<!-- How were these changes implemented? -->

**How**: 
- added and fixed types for the helpers into Cypress namespace using global declaration as described in TS docs https://www.typescriptlang.org/docs/handbook/declaration-files/templates/global-modifying-module-d-ts.html
- for testing - added `tsc --noemit` on sample ts project

<!-- Have you done all of these things?  -->

**Checklist**:

<!-- add "N/A" to the end of each line that's irrelevant to your changes -->

<!-- to check an item, place an "x" in the box like so: "- [x] Documentation" -->

* [x] Documentation 
* [x] Tests
* [x] Ready to be merged <!-- In your opinion, is this ready to be merged as soon as it's reviewed? -->
* [x] Added myself to contributors table <!-- this is optional, see the contributing guidelines for instructions -->

<!-- feel free to add additional comments -->

This is how types being picked up by VS-Code:

![image](https://user-images.githubusercontent.com/4506749/47946634-840d6d80-decb-11e8-9be7-62fb2a68526e.png)


![image](https://user-images.githubusercontent.com/4506749/47946573-9e931700-deca-11e8-94e0-4fd6bd70ce4c.png)

Author: Airat Aminev

.all-contributorsrc

@@ -50,6 +50,17 @@
         "ideas",
         "test"
       ]
+    },
+    {
+      "login": "airato",
+      "name": "Airat Aminev",
+      "avatar_url": "https://avatars3.githubusercontent.com/u/4506749?v=4",
+      "profile": "https://github.com/airato",
+      "contributions": [
+        "code",
+        "test",
+        "tool"
+      ]
     }
   ],
   "repoType": "github"

README.md

@@ -16,7 +16,7 @@
 [![downloads][downloads-badge]][npmtrends]
 [![MIT License][license-badge]][license]
 
-[![All Contributors](https://img.shields.io/badge/all_contributors-4-orange.svg?style=flat-square)](#contributors)
+[![All Contributors](https://img.shields.io/badge/all_contributors-5-orange.svg?style=flat-square)](#contributors)
 [![PRs Welcome][prs-badge]][prs]
 [![Code of Conduct][coc-badge]][coc]
 
@@ -100,8 +100,8 @@ Thanks goes to these people ([emoji key][emojis]):
 
 <!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
 <!-- prettier-ignore -->
-| [<img src="https://avatars.githubusercontent.com/u/1500684?v=3" width="100px;"/><br /><sub><b>Kent C. Dodds</b></sub>](https://kentcdodds.com)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Code") [📖](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Documentation") [🚇](#infra-kentcdodds "Infrastructure (Hosting, Build-Tools, etc)") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Tests") | [<img src="https://avatars2.githubusercontent.com/u/498274?v=4" width="100px;"/><br /><sub><b>Ivan Babak</b></sub>](https://sompylasar.github.io)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=sompylasar "Code") [🤔](#ideas-sompylasar "Ideas, Planning, & Feedback") | [<img src="https://avatars1.githubusercontent.com/u/4002543?v=4" width="100px;"/><br /><sub><b>Łukasz Gandecki</b></sub>](http://team.thebrain.pro)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=lgandecki "Code") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=lgandecki "Tests") | [<img src="https://avatars1.githubusercontent.com/u/25429764?v=4" width="100px;"/><br /><sub><b>Peter Kamps</b></sub>](https://github.com/npeterkamps)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Code") [📖](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Documentation") [🤔](#ideas-npeterkamps "Ideas, Planning, & Feedback") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Tests") |
-| :---: | :---: | :---: | :---: |
+| [<img src="https://avatars.githubusercontent.com/u/1500684?v=3" width="100px;"/><br /><sub><b>Kent C. Dodds</b></sub>](https://kentcdodds.com)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Code") [📖](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Documentation") [🚇](#infra-kentcdodds "Infrastructure (Hosting, Build-Tools, etc)") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=kentcdodds "Tests") | [<img src="https://avatars2.githubusercontent.com/u/498274?v=4" width="100px;"/><br /><sub><b>Ivan Babak</b></sub>](https://sompylasar.github.io)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=sompylasar "Code") [🤔](#ideas-sompylasar "Ideas, Planning, & Feedback") | [<img src="https://avatars1.githubusercontent.com/u/4002543?v=4" width="100px;"/><br /><sub><b>Łukasz Gandecki</b></sub>](http://team.thebrain.pro)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=lgandecki "Code") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=lgandecki "Tests") | [<img src="https://avatars1.githubusercontent.com/u/25429764?v=4" width="100px;"/><br /><sub><b>Peter Kamps</b></sub>](https://github.com/npeterkamps)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Code") [📖](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Documentation") [🤔](#ideas-npeterkamps "Ideas, Planning, & Feedback") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=npeterkamps "Tests") | [<img src="https://avatars3.githubusercontent.com/u/4506749?v=4" width="100px;"/><br /><sub><b>Airat Aminev</b></sub>](https://github.com/airato)<br />[💻](https://github.com/kentcdodds/cypress-testing-library/commits?author=airato "Code") [⚠️](https://github.com/kentcdodds/cypress-testing-library/commits?author=airato "Tests") [🔧](#tool-airato "Tools") |
+| :---: | :---: | :---: | :---: | :---: |
 
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 

package.json

@@ -11,14 +11,16 @@
     "add-contributor": "kcd-scripts contributors add",
     "build": "kcd-scripts build",
     "lint": "kcd-scripts lint",
-    "test": "npm-run-all --parallel test:unit test:cypress",
+    "test": "npm-run-all --parallel test:unit test:cypress test:typings",
     "test:unit": "kcd-scripts test --no-watch",
     "test:unit:watch": "kcd-scripts test",
     "test:cypress:serve": "serve --listen 13370 ./cypress/fixtures/test-app",
     "test:cypress:run": "wait-port --timeout 10000 localhost:13370 && cypress run",
     "test:cypress:open": "cypress open",
     "test:cypress": "npm-run-all --silent --parallel --race test:cypress:serve test:cypress:run",
     "test:cypress:dev": "npm-run-all --silent --parallel --race test:cypress:serve test:cypress:open",
+    "test:typings": "tsc -p tests/typescript-types/ --noemit",
+    "test:typings:watch": "tsc -p tests/typescript-types/ --noemit --watch",
     "validate": "kcd-scripts validate build,lint,test",
     "setup": "npm install && npm run validate -s",
     "precommit": "kcd-scripts precommit",
@@ -50,6 +52,7 @@
     "kcd-scripts": "^0.37.0",
     "npm-run-all": "^4.1.2",
     "serve": "^10.0.0",
+    "typescript": "^3.1.6",
     "wait-port": "^0.2.2"
   },
   "peerDependencies": {

tests/typescript-types/test.spec.ts

@@ -0,0 +1,45 @@
+describe('Foo', () => {
+  it('has proper types', () => {
+    cy.visit('#/foo')
+
+    cy.getAllByPlaceholderText('foo').should(elements => {
+      // argument should be an array of HTML elements
+      expect(elements.length).to.eq(0)
+      expect(elements[0].tagName).to.eq(0)
+    })
+
+    // with regex
+    cy.queryByPlaceholderText<'a'>(/foo/).should(element => {
+      // node can be null
+      if (element) {
+        // argument should be an anchor
+        expect(element.href).to.eq('')
+      }
+    })
+
+    // with matcher function
+    const matcherFn = (content: string, element: HTMLElement) => true
+
+    cy.queryByPlaceholderText<HTMLAudioElement>(matcherFn).should(element => {
+      // node can be null
+      if (element) {
+        // argument should be an Audio element
+        expect(element.play).to.exist
+      }
+    })
+
+    // with matcher options
+    cy.queryAllByPlaceholderText<HTMLAudioElement>('foo', {
+      collapseWhitespace: true,
+      exact: true,
+      trim: true,
+    }).should(elements => {
+      const el = elements[0]
+      // node can be null
+      if (el) {
+        // argument should be an array of Audio elements
+        expect(el.play).to.exist
+      }
+    })
+  })
+})

tests/typescript-types/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "lib": ["dom", "es2015", "es2016", "es2017"],
+    "target": "es2017",
+    "module": "esnext",
+    "moduleResolution": "node",
+    "experimentalDecorators": true,
+    "outDir": "dist",
+    "noUnusedLocals": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true,
+    "types": ["cypress", "../../typings"]
+  }
+}