feat: add typescript definitions

fixes #197

Author: satya164

.circleci/config.yml

@@ -30,14 +30,15 @@ jobs:
       - persist_to_workspace:
           root: .
           paths: .
-  lint-and-flow:
+  lint-and-typecheck:
       <<: *defaults
       steps:
         - attach_workspace:
             at: ~/linaria
         - run: |
             yarn lint
             yarn flow
+            yarn typescript
   unit-tests:
       <<: *defaults
       steps:
@@ -74,7 +75,7 @@ workflows:
   build-and-test:
     jobs:
       - install-dependencies
-      - lint-and-flow:
+      - lint-and-typecheck:
           requires:
             - install-dependencies
       - unit-tests:

package.json

@@ -3,8 +3,10 @@
   "version": "1.0.0-alpha.13",
   "description": "Blazing fast zero-runtime CSS in JS library",
   "main": "lib/index.js",
+  "types": "types/index.d.ts",
   "files": [
     "lib/",
+    "types/",
     "react.js",
     "server.js",
     "babel.js",
@@ -29,6 +31,7 @@
   "scripts": {
     "lint": "eslint .",
     "flow": "flow",
+    "typescript": "dtslint types",
     "test": "jest",
     "test:unit": "jest __tests__",
     "test:integration": "jest __integration-tests__",
@@ -50,12 +53,14 @@
     "@babel/preset-flow": "^7.0.0",
     "@babel/preset-react": "^7.0.0",
     "@callstack/eslint-config": "^2.0.0",
+    "@types/react": "^16.4.18",
     "all-contributors-cli": "^5.4.0",
     "babel-core": "^7.0.0-bridge.0",
     "codecov": "^3.1.0",
     "conventional-changelog-cli": "^2.0.5",
     "dedent": "^0.7.0",
     "del-cli": "^1.1.0",
+    "dtslint": "^0.3.0",
     "eslint": "^5.4.0",
     "flow-bin": "^0.79.1",
     "flow-copy-source": "^2.0.2",

src/react/styled.js

@@ -82,8 +82,9 @@ type StyledComponent<T> = React.ComponentType<T & { as?: React$ElementType }>;
 
 type StyledTag<T> = (strings: string[], ...exprs: Array<string | number | {} | (T => string | number)>) => StyledComponent<T>;
 
-declare module.exports: {|
+type StyledJSXIntrinsics = $ObjMap<$JSXIntrinsics, <T>({ props: T }) => StyledTag<T>>;
+
+declare module.exports: StyledJSXIntrinsics & {|
   <T>(T): StyledTag<React.ElementConfig<T>>,
-  [string]: StyledTag<{ children?: React.Node, [key: string]: any }>,
 |};
 */

types/index.d.ts

@@ -0,0 +1,49 @@
+// TypeScript Version: 2.8
+
+declare module 'linaria' {
+  function css(
+    strings: TemplateStringsArray,
+    ...exprs: Array<string | number | object>
+  ): string;
+
+  function cx(
+    ...classNames: Array<string | false | undefined | null | 0>
+  ): string;
+}
+
+declare module 'linaria/react' {
+  import * as React from 'react';
+
+  type InterpolationFunction<T> = (props: T) => string | number;
+
+  type StyledComponent<T> = React.StatelessComponent<
+    T & { as?: React.ReactType }
+  >;
+
+  type StyledTag<T> = (
+    strings: TemplateStringsArray,
+    ...exprs: Array<string | number | object | InterpolationFunction<T>>
+  ) => StyledComponent<T>;
+
+  type StyledJSXIntrinsics = {
+    [P in keyof JSX.IntrinsicElements]: StyledTag<
+      JSX.IntrinsicElements[P] & { [key: string]: any }
+    >
+  };
+
+  const styled: StyledJSXIntrinsics & {
+    <T>(component: React.ReactType<T>): StyledTag<T>;
+
+    [key: string]: StyledTag<{
+      children?: React.ReactNode;
+      [key: string]: any;
+    }>;
+  };
+}
+
+declare module 'linaria/server' {
+  function collect(
+    html: string,
+    css: string
+  ): { critical: string; other: string };
+}

types/tests/index.tsx

@@ -0,0 +1,46 @@
+import { css, cx } from 'linaria';
+
+const tomato = 'tomato';
+const border = 1;
+
+const absoluteFill = {
+  position: 'absolute',
+  top: 0,
+  left: 0,
+  bottom: 0,
+  right: 0,
+};
+
+// $ExpectType string
+css`
+  color: ${tomato};
+  border-width: ${border}px;
+
+  &.abs {
+    ${absoluteFill};
+  }
+`;
+
+// $ExpectType string
+css`font-family: sans-serif`;
+
+// $ExpectError
+css`color: ${true}`;
+
+// $ExpectError
+css`color: ${undefined}`;
+
+// $ExpectError
+css`color: ${null}`;
+
+// $ExpectType string
+cx('test', false, undefined, null, 0);
+
+// $ExpectError
+cx('test', 42);
+
+// $ExpectError
+cx('test', true);
+
+// $ExpectError
+cx('test', {});

types/tests/react.tsx

@@ -0,0 +1,58 @@
+import * as React from 'react';
+import { styled } from 'linaria/react';
+
+const white = 'white';
+const tomato = 'tomato';
+const border = 1;
+
+const absoluteFill = {
+  position: 'absolute',
+  top: 0,
+  left: 0,
+  bottom: 0,
+  right: 0,
+};
+
+const Button = styled.button`
+  color: ${white};
+  background-color: ${props => props.background};
+  border-width: ${border}px;
+
+  &.abs {
+    ${absoluteFill};
+  }
+`;
+
+const CustomButton = styled(Button)`
+  &:hover {
+    background-color: ${tomato};
+  }
+`;
+
+class Title extends React.Component<{ label: string; className?: string }> {
+  render() {
+    return <h1 className={this.props.className}>{this.props.label}</h1>;
+  }
+}
+
+const CustomTitle = styled(Title)`
+  font-family: sans-serif;
+`;
+
+// $Expect Element
+<Button as="a">Hello world</Button>;
+
+// $ExpectError
+<Button onClick={42}>Hello world</Button>;
+
+// $Expect Element
+<CustomButton onClick={() => alert('Clicked')}>Hello world</CustomButton>;
+
+// $Expect Element
+<CustomTitle label="Hello world" />;
+
+// $Expect Element
+<CustomTitle label="Hello world" className="primary" />;
+
+// $ExpectError
+<CustomTitle />;

types/tests/server.tsx

@@ -0,0 +1,7 @@
+import { collect } from 'linaria/server';
+
+// $ExpectType { critical: string; other: string; }
+collect(
+  '<div class="foo">Hello</div>',
+  '.foo { color: blue; }'
+);

types/tsconfig.json

@@ -0,0 +1,13 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "lib": ["es6", "dom"],
+    "noImplicitAny": true,
+    "noImplicitThis": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "noEmit": true,
+    "forceConsistentCasingInFileNames": true,
+    "jsx": "react"
+  }
+}