fix: list links of a block that _is a_ CID (#226)

Author: Alan Shaw

src/block.js

@@ -45,6 +45,10 @@ function * links (source, base) {
   if (source == null || source instanceof Uint8Array) {
     return
   }
+  const cid = CID.asCID(source)
+  if (cid) {
+    yield [base.join('/'), cid]
+  }
   for (const [key, value] of Object.entries(source)) {
     const path = /** @type {[string|number, string]} */ ([...base, key])
     yield * linksWithin(path, value)

test/test-block.spec.js

@@ -83,6 +83,17 @@ describe('block', () => {
     })
   })
 
+  it('links of a block that is a CID', async () => {
+    const block = await main.encode({ value: link, codec, hasher })
+    const links = []
+    for (const link of block.links()) {
+      links.push(link)
+    }
+    assert.equal(links.length, 1)
+    assert.equal(links[0][0], '')
+    assert.equal(links[0][1].toString(), link.toString())
+  })
+
   it('kitchen sink', () => {
     const sink = { one: { two: { arr: [true, false, null], three: 3, buff, link } } }
     const block = main.createUnsafe({