bech32 - npm Package Compare versions

Comparing version 0.0.1 to 0.0.2

index.js

@@ -0,1 +1,2 @@
+let assert = require('assert')
 let ALPHABET = 'qpzry9x8gf2tvdw0s3jn54khce6mua7l'
@@ -22,21 +23,53 @@
 
+function convertbits (data, inbits, outbits, pad) {
+  let val = 0
+  let bits = 0
+  let maxv = (1 << outbits) - 1
+  let ret = []
+
+  for (let i = 0; i < data.length; ++i) {
+    val = (val << inbits) | data[i]
+    bits += inbits
+
+    while (bits >= outbits) {
+      bits -= outbits
+      ret.push((val >> bits) & maxv)
+    }
+  }
+
+  if (pad) {
+    if (bits > 0) {
+      ret.push((val << (outbits - bits)) & maxv)
+    }
+  } else {
+//     assert(!((val << (outbits - bits)) & maxv))
+//     assert(bits < inbits)
+  }
+
+  return ret
+}
+
 function encode (prefix, data) {
+  data = Buffer.from(convertbits(data, 8, 5, true))
+
   // too long?
-  if ((prefix.length + 7 + data.length) > 90) return null
+  assert((prefix.length + 7 + data.length) <= 90)
 
   // determine chk mod
-  let chk = 0 | 0
+  let chk = 1
   for (let i = 0; i < prefix.length; ++i) {
-    let c = prefix.charCodeAt(i)
-    if (!(c >> 5)) return null
+    let c = prefix.charCodeAt(i) >> 5
+    assert.notEqual(c, 0)
 
-    chk = polymodStep(chk) ^ (c >> 5)
+    chk = polymodStep(chk) ^ c
   }
+  chk = polymodStep(chk)
 
   let result = ''
   for (let i = 0; i < prefix.length; ++i) {
-    let c = prefix.charCodeAt(i)
-    chk = polymodStep(chk) ^ (c & 0x1f)
+    let c = prefix.charAt(i)
+    let v = prefix.charCodeAt(i)
+    chk = polymodStep(chk) ^ (v & 0x1f)
 
-    result += String.fromCharCode(c)
+    result += c
   }
@@ -47,3 +80,4 @@ result += '1'
     let x = data[i]
-    if (x >> 5) return null
+    assert.equal(x >> 5, 0)
+
     chk = polymodStep(chk) ^ x
@@ -59,3 +93,3 @@ result += ALPHABET.charAt(x)
   for (let i = 0; i < 6; ++i) {
-    let v = chk >> ((5 - i) * 5) & 0x1f
+    let v = (chk >> ((5 - i) * 5)) & 0x1f
     result += ALPHABET.charAt(v)
@@ -68,16 +102,19 @@ }
 function decode (str) {
-  if (str.length > 90) return
+  assert(str.length >= 8)
+  assert(str.length <= 90)
 
   // don't allow mixed case
   let lowered = str.toLowerCase()
-  if (str !== lowered) return
+  assert.equal(str, lowered)
 
-  let pos = str.lastIndexOf('1')
-  if ((pos < 1) || (pos + 7 > str.length)) return
+  let split = str.lastIndexOf('1')
+  let prefix = str.slice(0, split)
+  let data = str.slice(split + 1)
+  assert(prefix.length >= 1)
+  assert(data.length >= 6)
 
-  let chk = 0
-  let prefix = str.substring(0, pos)
+  let chk = 1
   for (let i = 0; i < prefix.length; ++i) {
     let c = prefix.charCodeAt(i)
-    if (c < 33 || c > 126) return
+    assert(c >= 33 && c <= 126)
 
@@ -89,14 +126,16 @@ chk = polymodStep(chk) ^ (c >> 5)
   for (let i = 0; i < prefix.length; ++i) {
-    chk = polymodStep(chk) ^ (prefix.charCodeAt(i) & 0x1f)
+    let c = prefix.charCodeAt(i)
+    chk = polymodStep(chk) ^ (c & 0x1f)
   }
 
-  let data = str.substring(pos)
-  let result = Buffer.allocUnsafe(data.length - 6)
+  // NOTE: zero-fill required
+  let result = Buffer.alloc(data.length)
 
   for (let i = 0; i < data.length; ++i) {
-    let c = data[i] & 0x80
-    if (c === 0) return
+    let cv = data.charCodeAt(i)
+    assert.equal(cv & 0x80, 0)
 
+    let c = data.charAt(i)
     let v = ALPHABET_MAP[c]
-    if (v === undefined) return
+    assert.notEqual(v, undefined)
 
@@ -106,8 +145,9 @@ chk = polymodStep(chk) ^ v
     // not in the checksum?
-    if (i < data.length - 6) {
-      data.writeUInt8(v, i)
+    if (i + 6 < data.length) {
+      result.writeUInt8(v, i)
     }
   }
 
-  if (chk !== 1) return
+  assert.equal(chk & 0x1, 1)
+  result = Buffer.from(convertbits(result.slice(0, -3), 5, 8, false)).slice(0, -1)
 
@@ -114,0 +154,0 @@ return { prefix, data: result }

package.json

 {
   "name": "bech32",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "Bech32 encoding / decoding",
@@ -31,4 +31,5 @@ "keywords": [
   "scripts": {
-    "standard": "standard"
+    "standard": "standard",
+    "test": "tape test/index.js | tap-dot"
   }
 }

No alert changes

Improved metrics

Total package byte prevSize

4497

23.82%

Lines of code

118

38.82%

No dependency changes