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dingoskydingosky
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Refactor
entropyPerChar -> bitsPerChar
1 parent ad0d723 commit e310537

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3 files changed

+29
-29
lines changed

3 files changed

+29
-29
lines changed

‎lib/charSet.js‎

Lines changed: 13 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -4,11 +4,11 @@ class CharSet {
44
constructor(chars, ndxFn) {
55
this.chars = chars
66
this.ndxFn = ndxFn
7-
this.entropyPerChar = Math.floor(Math.log2(chars.length))
8-
if (this.entropyPerChar != Math.log2(chars.length)) {
7+
this.bitsPerChar = Math.floor(Math.log2(chars.length))
8+
if (this.bitsPerChar != Math.log2(chars.length)) {
99
throw new Error('EntropyString only supports CharSets with a power of 2 characters')
1010
}
11-
this.charsPerChunk = lcm(this.entropyPerChar, 8) / this.entropyPerChar
11+
this.charsPerChunk = lcm(this.bitsPerChar, 8) / this.bitsPerChar
1212
}
1313

1414
use(chars) {
@@ -54,28 +54,28 @@ const _ndx2 = (chunk, slice, bytes) => {
5454
return _ndxDiv(chunk, slice, bytes, 1)
5555
}
5656

57-
const _ndxGen = (chunk, slice, bytes, entropyPerChar) => {
57+
const _ndxGen = (chunk, slice, bytes, bitsPerChar) => {
5858
let bitsPerByte = 8
59-
let slicesPerChunk = lcm(entropyPerChar, bitsPerByte) / bitsPerByte
59+
let slicesPerChunk = lcm(bitsPerChar, bitsPerByte) / bitsPerByte
6060
let bNum = chunk * slicesPerChunk
6161

62-
let rShift = bitsPerByte - entropyPerChar
63-
let lOffset = Math.floor((slice*entropyPerChar)/bitsPerByte)
64-
let lShift = (slice*entropyPerChar) % bitsPerByte
62+
let rShift = bitsPerByte - bitsPerChar
63+
let lOffset = Math.floor((slice*bitsPerChar)/bitsPerByte)
64+
let lShift = (slice*bitsPerChar) % bitsPerByte
6565

6666
let ndx = ((bytes[bNum+lOffset]<<lShift)&0xff)>>rShift
6767

68-
let rOffset = Math.ceil((slice*entropyPerChar)/bitsPerByte)
69-
let rShiftIt = ((rOffset+1)*bitsPerByte - (slice+1)*entropyPerChar) % bitsPerByte
68+
let rOffset = Math.ceil((slice*bitsPerChar)/bitsPerByte)
69+
let rShiftIt = ((rOffset+1)*bitsPerByte - (slice+1)*bitsPerChar) % bitsPerByte
7070
if (rShift < rShiftIt) {
7171
ndx += bytes[bNum+rOffset]>>rShiftIt
7272
}
7373
return ndx
7474
}
7575

76-
const _ndxDiv = (chunk, slice, bytes, entropyPerChar) => {
77-
let lShift = entropyPerChar
78-
let rShift = 8 - entropyPerChar
76+
const _ndxDiv = (chunk, slice, bytes, bitsPerChar) => {
77+
let lShift = bitsPerChar
78+
let rShift = 8 - bitsPerChar
7979
return ((bytes[chunk]<<(lShift*slice))&0xff)>>rShift
8080
}
8181

‎lib/entropy.js‎

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -67,10 +67,10 @@ const stringWithBytes = (entropy, charSet, bytes) => {
6767
}
6868
if (entropy <= 0) { return '' }
6969

70-
const count = Math.ceil(entropy / charSet.entropyPerChar)
70+
const count = Math.ceil(entropy / charSet.bitsPerChar)
7171
if (count <= 0) { return '' }
7272

73-
const needed = Math.ceil(count * (charSet.entropyPerChar / _bitsPerByte))
73+
const needed = Math.ceil(count * (charSet.bitsPerChar / _bitsPerByte))
7474
if (bytes.length < needed) {
7575
throw new Error('Insufficient bytes')
7676
}
@@ -94,10 +94,10 @@ const stringWithBytes = (entropy, charSet, bytes) => {
9494

9595
const bytesNeeded = (entropy, charSet) => {
9696
if (!CharSet.isValid(charSet)) { throw new Error('Invalid CharSet') }
97-
const count = Math.ceil(entropy / charSet.entropyPerChar)
97+
const count = Math.ceil(entropy / charSet.bitsPerChar)
9898
if (count <= 0) { return 0 }
9999

100-
const bytesPerSlice = charSet.entropyPerChar / _bitsPerByte
100+
const bytesPerSlice = charSet.bitsPerChar / _bitsPerByte
101101
return Math.ceil(count * bytesPerSlice)
102102
}
103103

‎test/charSet.js‎

Lines changed: 12 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -5,48 +5,48 @@ import CharSet from '../lib/charSet';
55
test('char set 64', t => {
66
const charSet = CharSet.charSet64
77
t.is(charSet.chars.length, 64)
8-
const entropyPerChar = Math.log2(charSet.chars.length)
9-
t.is(charSet.entropyPerChar, entropyPerChar)
8+
const bitsPerChar = Math.log2(charSet.chars.length)
9+
t.is(charSet.bitsPerChar, bitsPerChar)
1010
t.is(charSet.charsPerChunk, 4)
1111
})
1212

1313
test('char set 32', t => {
1414
const charSet = CharSet.charSet32
1515
t.is(charSet.chars.length, 32)
16-
const entropyPerChar = Math.log2(charSet.chars.length)
17-
t.is(charSet.entropyPerChar, entropyPerChar)
16+
const bitsPerChar = Math.log2(charSet.chars.length)
17+
t.is(charSet.bitsPerChar, bitsPerChar)
1818
t.is(charSet.charsPerChunk, 8)
1919
})
2020

2121
test('char set 16', t => {
2222
const charSet = CharSet.charSet16
2323
t.is(charSet.chars.length, 16)
24-
const entropyPerChar = Math.log2(charSet.chars.length)
25-
t.is(charSet.entropyPerChar, entropyPerChar)
24+
const bitsPerChar = Math.log2(charSet.chars.length)
25+
t.is(charSet.bitsPerChar, bitsPerChar)
2626
t.is(charSet.charsPerChunk, 2)
2727
})
2828

2929
test('char set 8', t => {
3030
const charSet = CharSet.charSet8
3131
t.is(charSet.chars.length, 8)
32-
const entropyPerChar = Math.log2(charSet.chars.length)
33-
t.is(charSet.entropyPerChar, entropyPerChar)
32+
const bitsPerChar = Math.log2(charSet.chars.length)
33+
t.is(charSet.bitsPerChar, bitsPerChar)
3434
t.is(charSet.charsPerChunk, 8)
3535
})
3636

3737
test('char set 4', t => {
3838
const charSet = CharSet.charSet4
3939
t.is(charSet.chars.length, 4)
40-
const entropyPerChar = Math.log2(charSet.chars.length)
41-
t.is(charSet.entropyPerChar, entropyPerChar)
40+
const bitsPerChar = Math.log2(charSet.chars.length)
41+
t.is(charSet.bitsPerChar, bitsPerChar)
4242
t.is(charSet.charsPerChunk, 4)
4343
})
4444

4545
test('char set 2', t => {
4646
const charSet = CharSet.charSet2
4747
t.is(charSet.chars.length, 2)
48-
const entropyPerChar = Math.log2(charSet.chars.length)
49-
t.is(charSet.entropyPerChar, entropyPerChar)
48+
const bitsPerChar = Math.log2(charSet.chars.length)
49+
t.is(charSet.bitsPerChar, bitsPerChar)
5050
t.is(charSet.charsPerChunk, 8)
5151
})
5252

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