urbit-ob

commit 14a24542282dd75a37aa1b5a05c456a7b7a9754f
parent c04222df4939d4fc8ae9a36420fc52a54e068423
Author: Jared Tobin <jared@jtobin.io>
Date:   Wed, 10 Oct 2018 16:37:22 +1300

Add eqPatq function.

* Add eqPatq for comparing @q values (i.e. modulo leading zero bytes).
* Minor version bump.
* Track CHANGELOG

Diffstat:
A
CHANGELOG
 | 
5
+++++
M
package.json
 | 
6
+++---
M
src/index.js
 | 
41
+++++++++++++++++++++++++++++++++++++++++
M
test/property.js
 | 
17
+++--------------

4 files changed, 52 insertions(+), 17 deletions(-)
diff --git a/CHANGELOG b/CHANGELOG
@@ -0,0 +1,5 @@
+# Changelog
+
+- 1.4.0 (2018-10-10)
+		* Add 'eqPatq' function for comparing @q values for equality (i.e., modulo
+			leading zero bytes).
diff --git a/package.json b/package.json
@@ -1,10 +1,10 @@
 {
   "name": "ob-js",
-  "version": "1.3.0",
-  "description": "utilities to convert urbit ship names back and forth between @p and @ud",
+  "version": "1.4.0",
+  "description": "Utilities for Hoon-style atom printing and conversion",
   "main": "dist/index.js",
   "scripts": {
-    "test": "jest test/*.test.js && mocha test/property.js",
+    "test": "jest --coverage test/*.test.js && mocha test/property.js",
     "build": "gulp"
   },
   "keywords": [
diff --git a/src/index.js b/src/index.js
@@ -431,6 +431,44 @@ patq2hex = str => {
   return splat.join('')
 }
 
+
+/**
+ * Remove all leading zero bytes from a hex-encoded string.
+ * @param  {string}  str a hex encoded string
+ * @return  {string}
+ */
+const removeLeadingZeroBytes = str =>
+  str.slice(0, 2) === '00'
+  ? removeLeadingZeroBytes(str.slice(2))
+  : str
+
+
+
+/**
+ * Equality comparison, modulo leading zero bytes.
+ * @param  {string}  s a hex-encoded string
+ * @param  {string}  t a hex-encoded string
+ * @return  {bool}
+ */
+const eqModLeadingZeroBytes = (s, t) =>
+  removeLeadingZeroBytes(s) === removeLeadingZeroBytes(t)
+
+
+
+/**
+ * Equality comparison on @q values.
+ * @param  {string}  p a @q-encoded string
+ * @param  {string}  q a @q-encoded string
+ * @return  {bool}
+ */
+const eqPatq = (p, q) => {
+  phex = patq2hex(p)
+  qhex = patq2hex(q)
+  return eqModLeadingZeroBytes(phex, qhex)
+}
+
+
+
 // returns the class of a ship from it's name
 const tierOfpatp = name => {
   const l = len(patp2arr(name))
@@ -578,6 +616,7 @@ module.exports = {
   patq: patq,
   hex2patq: hex2patq,
   patq2hex: patq2hex,
+  eqPatq: eqPatq,
 
   sein: sein,
   _clan: clan,
@@ -606,6 +645,8 @@ module.exports = {
   _dec2bin: dec2bin,
   _syl2bin: syl2bin,
 
+  _eqModLeadingZeroBytes: eqModLeadingZeroBytes,
+
   _met: met,
 
   _arr2patp: arr2patp
diff --git a/test/property.js b/test/property.js
@@ -4,14 +4,6 @@ const jsc = require('jsverify')
 const ob = require('../src')
 const bn = require('bn.js')
 
-removeLeadingZeroBytes = str =>
-  str.slice(0, 2) === '00'
-  ? removeLeadingZeroBytes(str.slice(2))
-  : str
-
-eqModLeadingZeroBytes = (s, t) =>
-  removeLeadingZeroBytes(s) === removeLeadingZeroBytes(t)
-
 describe('@q encoding', () => {
 
   let hexString = jsc.string.smap(
@@ -19,18 +11,15 @@ describe('@q encoding', () => {
     x => Buffer.from(x, 'hex').toString()
   )
 
-  let patq = hexString.smap(
-    hex => ob.patq(new bn(hex, 'hex')),
-    pq => ob.patq2hex(pq)
-  )
+  let patq = hexString.smap(ob.hex2patq, ob.patq2hex)
 
   it('patq2hex and hex2patq are inverses', () => {
     let iso0 = jsc.forall(hexString, hex =>
-      eqModLeadingZeroBytes(ob.patq2hex(ob.hex2patq(hex)), hex)
+      ob._eqModLeadingZeroBytes(ob.patq2hex(ob.hex2patq(hex)), hex)
     )
 
     let iso1 = jsc.forall(patq, str =>
-      ob.hex2patq(ob.patq2hex(str)) === str
+      ob.eqPatq(ob.hex2patq(ob.patq2hex(str)), str)
     )
 
     jsc.assert(iso0, { tests: 200 })