eslint: use prefer-const.

.eslintrc.json

@@ -36,6 +36,10 @@
     "no-extra-semi": 0,
     "handle-callback-err": 0,
     "no-buffer-constructor": 2,
-    "no-tabs": 2
+    "no-tabs": 2,
+    "prefer-const": ["error", {
+      "destructuring": "all",
+      "ignoreReadBeforeAssign": true
+    }]
   }
 }

bench/bech32.js

@@ -6,7 +6,7 @@ const bench = require('./bench');
 
 let i, end, addr;
 
-let addrs = [];
+const addrs = [];
 
 end = bench('serialize');
 for (i = 0; i < 100000; i++) {

bench/bench.js

@@ -1,11 +1,11 @@
 'use strict';
 
 module.exports = function bench(name) {
-  let start = process.hrtime();
+  const start = process.hrtime();
   return function end(ops) {
-    let elapsed = process.hrtime(start);
-    let time = elapsed[0] + elapsed[1] / 1e9;
-    let rate = ops / time;
+    const elapsed = process.hrtime(start);
+    const time = elapsed[0] + elapsed[1] / 1e9;
+    const rate = ops / time;
 
     console.log('%s: ops=%d, time=%d, rate=%s',
       name, ops, time, rate.toFixed(5));

bench/coins.js

@@ -6,7 +6,7 @@ const TX = require('../lib/primitives/tx');
 const bench = require('./bench');
 
 let raw = fs.readFileSync(`${__dirname}/../test/data/wtx.hex`, 'utf8');
-let wtx = TX.fromRaw(raw.trim(), 'hex');
+const wtx = TX.fromRaw(raw.trim(), 'hex');
 let coins = Coins.fromTX(wtx, 1);
 let i, j, end, hash;
 

bench/merkle.js

@@ -11,10 +11,10 @@ for (let i = 0; i < 3000; i++)
   leaves.push(random.randomBytes(32));
 
 {
-  let end = bench('tree');
+  const end = bench('tree');
   let i;
   for (i = 0; i < 1000; i++) {
-    let [n, m] = merkle.createTree(leaves.slice());
+    const [n, m] = merkle.createTree(leaves.slice());
     assert(n);
     assert(!m);
   }

bench/mnemonic.js

@@ -5,10 +5,10 @@ const bench = require('./bench');
 const HD = require('../lib/hd');
 const Mnemonic = require('../lib/hd/mnemonic');
 
-let mnemonic = new Mnemonic();
+const mnemonic = new Mnemonic();
 HD.fromMnemonic(mnemonic);
 
-let phrase = mnemonic.getPhrase();
+const phrase = mnemonic.getPhrase();
 let i, end;
 
 assert.equal(Mnemonic.fromPhrase(phrase).getPhrase(), phrase);

bench/tx.js

@@ -12,11 +12,11 @@ const encoding = require('../lib/utils/encoding');
 const random = require('../lib/crypto/random');
 const bench = require('./bench');
 
-let json = require('../test/data/block300025.json');
-let block = Block.fromJSON(json);
-let btx = { tx: block.txs[397], view: new CoinView() };
+const json = require('../test/data/block300025.json');
+const block = Block.fromJSON(json);
+const btx = { tx: block.txs[397], view: new CoinView() };
 
-let tx3 = parseTX('../test/data/tx3.hex');
+const tx3 = parseTX('../test/data/tx3.hex');
 let wtx = fs.readFileSync(`${__dirname}/../test/data/wtx.hex`, 'utf8');
 let i, tx, end, flags, input;
 
@@ -29,11 +29,11 @@ for (i = 0; i < tx.inputs.length; i++) {
 }
 
 function parseTX(file) {
-  let data = fs.readFileSync(`${__dirname}/${file}`, 'utf8');
-  let parts = data.trim().split(/\n+/);
+  const data = fs.readFileSync(`${__dirname}/${file}`, 'utf8');
+  const parts = data.trim().split(/\n+/);
   let raw = parts[0];
-  let tx = TX.fromRaw(raw.trim(), 'hex');
-  let view = new CoinView();
+  const tx = TX.fromRaw(raw.trim(), 'hex');
+  const view = new CoinView();
   let i, prev;
 
   for (i = 1; i < parts.length; i++) {
@@ -97,7 +97,7 @@ for (i = 0; i < 3000; i++)
 end(i * tx3.tx.inputs.length);
 
 end = bench('verify2');
-let script = tx3.view.getOutputFor(tx3.tx.inputs[0]).script;
+const script = tx3.view.getOutputFor(tx3.tx.inputs[0]).script;
 for (i = 0; i < 100000; i++)
   tx3.tx.signatureHashV0(0, script, Script.hashType.ALL);
 end(i);

bench/walletdb.js

@@ -8,7 +8,7 @@ const Outpoint = require('../lib/primitives/outpoint');
 let walletdb;
 
 function dummy() {
-  let hash = random.randomBytes(32).toString('hex');
+  const hash = random.randomBytes(32).toString('hex');
   return new Outpoint(hash, 0);
 }