add hw2

node_modules/khroma/test/methods/rgba.js

@@ -0,0 +1,58 @@
+
+/* IMPORT */
+
+import {describe} from 'fava';
+import {rgba} from '../../dist/index.js';
+
+/* MAIN */
+
+describe ( 'rgba', it => {
+
+  it ( 'creates a new color given its rgba channels', t => {
+
+    const tests = [
+      [[0, 0, 0, 0], 'rgba(0, 0, 0, 0)'],
+      [[255, 255, 255, 0.5], 'rgba(255, 255, 255, 0.5)'],
+      [[0, 0, 0, 1], '#000000'],
+      [[128, 128, 128, 1], '#808080'],
+      [[-1, -1, -1, -1], 'rgba(0, 0, 0, 0)'],
+      [[1000, 1000, 1000, 1000], '#ffffff']
+    ];
+
+    tests.forEach ( ([ args, output ]) => {
+      t.is ( rgba ( ...args ), output );
+    });
+
+  });
+
+  it ( 'sets the opacity', t => {
+
+    const tests = [
+      [['#000000', .5], 'rgba(0, 0, 0, 0.5)'],
+      [['#00000066', .5], 'rgba(0, 0, 0, 0.5)'],
+      [['#ffffff', .5], 'rgba(255, 255, 255, 0.5)'],
+      [['#ffffff66', .5], 'rgba(255, 255, 255, 0.5)'],
+      [['#ffcc00', .5], 'rgba(255, 204, 0, 0.5)'],
+      [['#ffcc0066', .5], 'rgba(255, 204, 0, 0.5)']
+    ];
+
+    tests.forEach ( ([ args, output ]) => {
+      t.is ( rgba ( ...args ), output );
+    });
+
+  });
+
+  it ( 'allows ommiting the alpha channel', t => {
+
+    const tests = [
+      [[0, 0, 0], '#000000'],
+      [[255, 255, 255], '#ffffff']
+    ];
+
+    tests.forEach ( ([ args, output ]) => {
+      t.is ( rgba ( ...args ), output );
+    });
+
+  });
+
+});