Factor data-to-JSON-string construction out of stitches.

This is a recurring and nameable operation; let's give it a name before we use it further.

1 files changed, 36 insertions, 0 deletions

diff --git a/ui/lib/swatch/json.test.js b/ui/lib/swatch/json.test.js
new file mode 100644
index 0000000..e01017d
--- /dev/null
+++ b/ui/lib/swatch/json.test.js
@@ -0,0 +1,36 @@
+import * as json from './json.js';
+import { expect, describe, it } from 'vitest';
+
+describe('encode', async () => {
+  it('converts atoms', async () => {
+    expect(json.encode(0)).toStrictEqual('0');
+    expect(json.encode('hello')).toStrictEqual('"hello"');
+    expect(json.encode(null)).toStrictEqual('null');
+    expect(json.encode(true)).toStrictEqual('true');
+  });
+
+  it('converts lists with indentation', async () => {
+    expect(json.encode([])).toStrictEqual('[]');
+    expect(json.encode(['hello', 'world'])).toStrictEqual('[\n  "hello",\n  "world"\n]');
+  });
+
+  it('converts objects with indentation', async () => {
+    expect(json.encode({})).toStrictEqual('{}');
+    expect(json.encode({ field: 'value' })).toStrictEqual('{\n  "field": "value"\n}');
+  });
+});
+
+describe('decode', async () => {
+  it('converts valid json values', async () => {
+    expect(json.decode('0')).toStrictEqual(0);
+    expect(json.decode('null')).toStrictEqual(null);
+    expect(json.decode('{}')).toStrictEqual({});
+    expect(json.decode('[1, 2, "3"]')).toStrictEqual([1, 2, '3']);
+  });
+
+  it('converts invalid json to `undefined`', async () => {
+    expect(json.decode('')).toBeUndefined();
+    expect(json.decode('{"foo":')).toBeUndefined();
+    expect(json.decode('arbitrary nonsense')).toBeUndefined();
+  });
+});