Refactor Tailwind config, add tests

jest.config.js

@@ -1,7 +1,4 @@
 module.exports = {
-  'projects': [
-    '<rootDir>/app/soapbox',
-  ],
   'testPathIgnorePatterns': [
     '<rootDir>/node_modules/',
     '<rootDir>/vendor/',

tailwind.config.js

@@ -1,37 +1,4 @@
-// https://tailwindcss.com/docs/customizing-colors#using-css-variables
-function withOpacityValue(variable) {
-  return ({ opacityValue }) => {
-    if (opacityValue === undefined) {
-      return `rgb(var(${variable}))`;
-    }
-    return `rgb(var(${variable}) / ${opacityValue})`;
-  };
-}
-
-// Parse list of shades into Tailwind function with CSS variables
-const parseShades = (color, shades) => {
-  return shades.reduce((obj, shade) => {
-    obj[shade] = withOpacityValue(`--color-${color}-${shade}`);
-    return obj;
-  }, {});
-};
-
-// Parse color matrix into Tailwind colors object
-const parseColors = colors => {
-  return Object.keys(colors).reduce((obj, color) => {
-    obj[color] = parseShades(color, colors[color]);
-    return obj;
-  }, {});
-};
-
-// Define color matrix (of available colors)
-const colors = {
-  gray: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
-  primary: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
-  success: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
-  danger: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
-  accent: [300, 500],
-};
+const { parseColorMatrix, withOpacityValue } = require('./tailwind/colors');
 
 module.exports = {
   content: ['./app/**/*.{html,js,ts,tsx}'],
@@ -66,7 +33,15 @@ module.exports = {
           'Noto Color Emoji',
         ],
       },
-      colors: Object.assign(parseColors(colors), {
+      colors: Object.assign(parseColorMatrix({
+        // Define color matrix (of available colors)
+        // Colors are configured at runtime with CSS variables in soapbox.json
+        gray: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+        primary: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+        success: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+        danger: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+        accent: [300, 500],
+      }), {
         'gradient-purple': withOpacityValue('--color-gradient-purple'),
         'gradient-blue': withOpacityValue('--color-gradient-blue'),
         'sea-blue': withOpacityValue('--color-sea-blue'),

tailwind/__tests__/colors-test.js

@@ -0,0 +1,35 @@
+import {
+  withOpacityValue,
+  parseColorMatrix,
+} from '../colors';
+
+describe('withOpacityValue()', () => {
+  it('returns a Tailwind color function with alpha support', () => {
+    const result = withOpacityValue('--color-primary-500');
+
+    // It returns a function
+    expect(typeof result).toBe('function');
+
+    // Test calling the function
+    expect(result({})).toBe('rgb(var(--color-primary-500))');
+    expect(result({ opacityValue: .5 })).toBe('rgb(var(--color-primary-500) / 0.5)');
+  });
+});
+
+describe('parseColorMatrix()', () => {
+  it('returns a Tailwind color object', () => {
+    const colorMatrix = {
+      gray: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+      primary: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+      success: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+      danger: [50, 100, 200, 300, 400, 500, 600, 700, 800, 900],
+      accent: [300, 500],
+    };
+
+    const result = parseColorMatrix(colorMatrix);
+
+    // Colors are mapped to functions which return CSS values
+    expect(result.primary[500]({})).toEqual('rgb(var(--color-primary-500))');
+    expect(result.accent[300]({ opacityValue: .5 })).toEqual('rgb(var(--color-accent-300) / 0.5)');
+  });
+});

tailwind/colors.js

@@ -0,0 +1,30 @@
+// https://tailwindcss.com/docs/customizing-colors#using-css-variables
+function withOpacityValue(variable) {
+  return ({ opacityValue }) => {
+    if (opacityValue === undefined) {
+      return `rgb(var(${variable}))`;
+    }
+    return `rgb(var(${variable}) / ${opacityValue})`;
+  };
+}
+
+// Parse list of shades into Tailwind function with CSS variables
+const parseShades = (color, shades) => {
+  return shades.reduce((obj, shade) => {
+    obj[shade] = withOpacityValue(`--color-${color}-${shade}`);
+    return obj;
+  }, {});
+};
+
+// Parse color matrix into Tailwind colors object
+const parseColorMatrix = colors => {
+  return Object.keys(colors).reduce((obj, color) => {
+    obj[color] = parseShades(color, colors[color]);
+    return obj;
+  }, {});
+};
+
+module.exports = {
+  withOpacityValue,
+  parseColorMatrix,
+};