fix: Specify types instead of extensions

Author: dignifiedquire

src/block.js

@@ -2,7 +2,7 @@
 const util = require('./util')
 
 // Immutable block of data
-function Block (data, extension) {
+function Block (data, type) {
   if (!data) {
     throw new Error('Block must be constructed with data')
   }
@@ -18,7 +18,20 @@ function Block (data, extension) {
   }
 
   this.key = util.hash(this.data)
-  this.extension = extension || 'data'
+  this.type = type || 'protobuf'
 }
 
+Object.defineProperty(Block.prototype, 'extension', {
+  get () {
+    switch (this.type) {
+      case 'protobuf':
+        return 'data'
+      case 'ipld':
+        return 'ipld'
+      default:
+        return this.type
+    }
+  }
+})
+
 module.exports = Block

test/block.spec.js

@@ -31,4 +31,23 @@ describe('block', () => {
 
     expect(key.equals(block.key)).to.equal(false)
   })
+
+  it('has the right extension to type mapping', () => {
+    const b1 = new Block('hello', 'protobuf')
+    const b2 = new Block('hello')
+    const b3 = new Block('hello', 'ipld')
+    const b4 = new Block('hello', 'woot')
+
+    expect(b1.type).to.be.eql('protobuf')
+    expect(b1.extension).to.be.eql('data')
+
+    expect(b2.type).to.be.eql('protobuf')
+    expect(b2.extension).to.be.eql('data')
+
+    expect(b3.type).to.be.eql('ipld')
+    expect(b3.extension).to.be.eql('ipld')
+
+    expect(b4.type).to.be.eql('woot')
+    expect(b4.extension).to.be.eql('woot')
+  })
 })