Bump word-wrap from 1.2.3 to 1.2.4

22-assert/01-ok.js

@@ -0,0 +1,22 @@
+#!/usr/bin/env node
+
+const assert = require('assert');
+
+assert.ok(1, 'MSG:5');
+assert.ok(true, 'MSG:6');
+assert.ok('abc', 'MSG:7');
+
+// assert.ok(0, 'MSG:9');
+// assert.ok(false, 'MSG:10');
+
+/*
+ * 下面的代码等价于上面，但是更简洁。
+ * 去掉 9, 10, 19, 20 行的代码注释，会抛出异常。
+ */
+
+assert(1, 'MSG:17');
+assert(true, 'MSG:18');
+assert('abc', 'MSG:19');
+
+// assert(0, 'MSG:21');
+// assert(false, 'MSG:22');

22-assert/02-equal.js

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+#!/usr/bin/env node
+
+const assert = require('assert');
+
+assert.equal(1, 1, 'MSG:5');
+assert.equal(true, true, 'MSG:6');
+assert.equal('abc', 'abc', 'MSG:7');
+
+// assert.equal(0, 1, 'MSG:9');
+// assert.equal(false, true, 'MSG:10');
+
+/*
+ * 下面的代码是反向断言
+ */
+
+assert.notEqual(0, 1, 'MSG:17');
+assert.notEqual(false, true, 'MSG:18');
+assert.notEqual('abc', 'def', 'MSG:19');
+
+// assert.notEqual(0, 0, 'MSG:21');
+// assert.notEqual(false, false, 'MSG:22');
+
+/*
+ * deepEqual
+ */
+
+const a = {a: {b: 1}};
+const b = {a: {b: 1}};
+const c = a;
+
+assert.equal(a, c);
+assert.deepEqual(a, b);
+// assert.equal(a, b, 'MSG:32');
+
+// a, b 两个对象的地址不同，equal 比较的是地址
+// 如果要比较两个对象的内容，需要用 deepEqual

22-assert/03-match.js

@@ -0,0 +1,18 @@
+#!/usr/bin/env node
+
+const assert = require('assert');
+
+// assert.match('I will fail', /pass/, 'MSG:5');
+// assert.match(123, /pass/, 'MSG:6');
+assert.match('I will pass', /pass/, 'MSG:7');
+
+/*
+ * 下面的代码是反向断言
+ */
+
+assert.doesNotMatch('I will fail', /pass/, 'MSG:13');
+assert.doesNotMatch('123', /pass/, 'MSG:14');
+// assert.doesNotMatch(123, /pass/, 'MSG:15');
+// assert.doesNotMatch('I will pass', /pass/, 'MSG:16');
+
+/* MSG:15 代码断言失败的原因是 123 类型不对 */

22-assert/04-throws.js

@@ -0,0 +1,20 @@
+#!/usr/bin/env node
+
+const assert = require('assert');
+
+assert.throws(
+  () => {
+    console.log('arrow function');
+    throw new Error('Wrong value');
+  },
+  Error,
+  'MSG:11'
+);
+
+// assert.throws(
+//   () => {
+//     throw new Error('Wrong value');
+//   },
+//   TypeError,
+//   'MSG:19'
+// );

22-assert/05-rejects.js

@@ -0,0 +1,23 @@
+#!/usr/bin/env node
+
+/* global Promise:true */
+
+const assert = require('assert');
+
+assert.rejects(
+  Promise.reject(new Error('Wrong value')),
+  Error,
+  'MSG:8'
+);
+
+// assert.rejects(
+//   Promise.reject(new Error('Wrong value')),
+//   TypeError,
+//   'MSG:14'
+// );
+
+// assert.rejects(
+//   Promise.resolve(new Error('Wrong value')),
+//   Error,
+//   'MSG:20'
+// );

22-assert/06-if-error.js

@@ -0,0 +1,14 @@
+#!/usr/bin/env node
+
+const fs = require('fs');
+const assert = require('assert');
+
+fs.readFile('./01-ok.js', (err, buf) => {
+  assert.ifError(err);
+  console.log(buf.toString('utf8'));
+});
+
+// fs.readFile('xyz', (err, buf) => {
+//   assert.ifError(err);
+//   console.log(buf.toString('utf8'));
+// });

22-assert/07-entropy.js

@@ -0,0 +1,16 @@
+#!/usr/bin/env node
+
+const { h, roundFractional } = require('./lib');
+const log = console.log;
+
+log('2.34 =', roundFractional(2.34, 1));
+log('h(0.5, 0.5) =', h([0.5, 0.5]));
+
+// log('2.34 =', roundFractional(true, 1));
+log('2.34 =', roundFractional(2.34, -1));
+
+// log('h(0.5, 0.5) =', h());
+// log('h(0.5, 0.5) =', h([]));
+// log('h(0.5, 0.5) =', h(['0.1', '0.9']));
+// log('h(0.5, 0.5) =', h([2, 0.3]));
+// log('h(0.5, 0.5) =', h([0.2, 0.3]));

22-assert/lib.js

@@ -0,0 +1,44 @@
+const assert = require('assert');
+
+/**
+ * 计算信源熵
+ *
+ * h(p) = -p1*log2(p1) - p2*log2(p2) - ... - pn*log2(pn)
+ *
+ * 0 <= pi <= 1 and p1 + p2 + ... + pn = 1
+ *
+ * @param p 概率分布数组
+ * @returns 返回信源熵
+ */
+function h(p) {
+  assert(p instanceof Array, `${p} 不是数组类型`);
+  assert.notEqual(p.length, 0, '数组为空');
+  let total = 0;
+  p.forEach(pi => {
+    assert.equal(typeof pi, 'number', `${pi} 不是数值类型`);
+    assert(pi <= 1 && pi >=0, `${pi} 取值不在 [0-1] 之间`);
+    total += pi;
+  });
+  assert.equal(total, 1, `${p} 的概率空间不封闭`);
+
+  return p.reduce((total, pi) => total - pi * Math.log2(pi), 0);
+}
+
+/**
+ * 小数点后面保留第 n 位
+ *
+ * @param x 做近似处理的数
+ * @param n 小数点后第 n 位
+ * @returns 近似处理后的数
+ */
+function roundFractional(x, n) {
+  // assert(typeof x === 'number', `${x} 不是数值类型`);
+  // assert(typeof n === 'number', `${n} 不是数值类型`);
+  assert.equal(typeof x, 'number', `${x} 不是数值类型`);
+  assert.equal(typeof n, 'number', `${n} 不是数值类型`);
+  assert(n > 0, `${n} 不是正整数`);
+
+  return Math.round(x * Math.pow(10, n)) / Math.pow(10, n);
+}
+
+module.exports = { h, roundFractional };

25-vm/01-byte-code.js

@@ -0,0 +1,15 @@
+#!/usr/bin/env node
+
+const vm = require('vm'),
+      fs = require('fs');
+
+const code = fs.readFileSync('./main.js', 'utf8');
+console.log(code);
+
+const script = new vm.Script(code, {
+  produceCachedData: true
+});
+const byteCodeBuffer = script.cachedData;
+console.log(byteCodeBuffer.length);
+console.log(byteCodeBuffer);
+fs.writeFileSync('./code.bin', byteCodeBuffer);

25-vm/02-run.js

@@ -0,0 +1,13 @@
+#!/usr/bin/env node
+
+const vm = require('vm'),
+      fs = require('fs');
+
+const byteCodeBuffer = fs.readFileSync('./code.bin');
+const length = byteCodeBuffer.readIntLE(8, 4);
+console.log(length);
+const anotherScript = new vm.Script(
+  ' '.repeat(length),
+  {cachedData: byteCodeBuffer}
+);
+anotherScript.runInThisContext();

25-vm/code.js

@@ -0,0 +1,26 @@
+#!/usr/bin/env node
+
+const log = console.log;
+
+log(`architecture: ${process.arch}`);
+log(`platform:     ${process.platform}\n`);
+
+log(`process id:   ${process.pid}`);
+log(`exePath:      ${process.execPath}\n`);
+
+log(`node version: ${process.version}`);
+log(`user id:      ${process.getuid()}`);
+log(`group id:     ${process.getgid()}`);
+log(`cwd:          ${process.cwd()}\n`);
+
+log(`rss:       ${process.memoryUsage().rss}`);
+log(`heapTotal: ${process.memoryUsage().heapTotal}`);
+log(`heapUsed:  ${process.memoryUsage().heapUsed}`);
+log(`external:  ${process.memoryUsage().external}\n`);
+
+log('env:');
+log(process.env);
+log(`host name: ${process.env.HOSTNAME}`);
+
+console.log('\nApp config:');
+log(process.config);

25-vm/main.js

@@ -0,0 +1,5 @@
+function add(a, b) {
+  return a + b;
+}
+
+console.log(add(2, 3));

26-web-assembly/01-hello-world.c

@@ -0,0 +1,5 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[]) {
+  printf("hello world\n");
+}

26-web-assembly/02-js-api.js

@@ -0,0 +1,21 @@
+#!/usr/bin/env node
+
+/* global WebAssembly, Uint8Array: true */
+const assert = require('assert');
+const {readFileSync} = require('fs');
+
+async function main() {
+  const buf = new Uint8Array(readFileSync('./02-js-api.wasm'));
+  assert(WebAssembly.validate(buf), '非法的 wasm 文件');
+  const importObj = {
+    imports: {
+      imported_func: arg => console.log(arg)
+    }
+  };
+
+  const {exported_func} = await WebAssembly.instantiate(buf, importObj)
+    .then(res => res.instance.exports);
+  exported_func();
+}
+
+main();

26-web-assembly/02-js-api.wat

@@ -0,0 +1,8 @@
+(module
+  (type (;0;) (func (param i32)))
+  (type (;1;) (func))
+  (import "imports" "imported_func" (func (;0;) (type 0)))
+  (func (;1;) (type 1)
+    i32.const 42
+    call 0)
+  (export "exported_func" (func 1)))