From 209d154a1da920f2141afb62737799a7ca9f0936 Mon Sep 17 00:00:00 2001
From: YangJ0605 <1442122744@qq.com>
Date: Sat, 6 Jun 2020 19:11:03 +0800
Subject: [PATCH] =?UTF-8?q?promise=20=E5=AE=9E=E7=8E=B02?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 0606/age.txt                    |   1 +
 0606/event.js                   |  33 ++++++
 0606/fs.js                      |  16 +++
 0606/name.txt                   |   1 +
 0606/pormise2.js                | 120 +++++++++++++++++++
 0606/promise.js                 | 201 ++++++++++++++++++++++++++++++++
 0606/test.js                    |  24 ++++
 better-scroll/1.js              |  17 +++
 better-scroll/1.txt             |   1 +
 better-scroll/package-lock.json |  23 ++++
 better-scroll/package.json      |  17 +++
 11 files changed, 454 insertions(+)
 create mode 100644 0606/age.txt
 create mode 100644 0606/event.js
 create mode 100644 0606/fs.js
 create mode 100644 0606/name.txt
 create mode 100644 0606/pormise2.js
 create mode 100644 0606/promise.js
 create mode 100644 0606/test.js
 create mode 100644 better-scroll/1.js
 create mode 100644 better-scroll/1.txt
 create mode 100644 better-scroll/package-lock.json
 create mode 100644 better-scroll/package.json

diff --git a/0606/age.txt b/0606/age.txt
new file mode 100644
index 0000000..8fdd954
--- /dev/null
+++ b/0606/age.txt
@@ -0,0 +1 @@
+22
\ No newline at end of file
diff --git a/0606/event.js b/0606/event.js
new file mode 100644
index 0000000..f236d6b
--- /dev/null
+++ b/0606/event.js
@@ -0,0 +1,33 @@
+const fs = require('fs')
+let cc = {}
+
+let event = {
+  arr:[],
+  on(fn) {
+    this.arr.push(fn)
+  },
+  emit() {
+    this.arr.forEach(fn => fn())
+  }
+}
+
+event.on(() => {
+  console.log('订阅ok')
+})
+
+event.on(() => {
+  // console.log(Object.keys(cc))
+  // console.log(Object.keys(cc))
+  if(Object.keys(cc).length === 2) {
+    console.log(cc)
+  }
+})
+
+fs.readFile('name.txt', (err, data) => {
+  cc['name'] = data.toString()
+  event.emit()
+})
+fs.readFile('age.txt', (err, data) => {
+  cc['age'] = data.toString()
+  event.emit()
+})
\ No newline at end of file
diff --git a/0606/fs.js b/0606/fs.js
new file mode 100644
index 0000000..423c099
--- /dev/null
+++ b/0606/fs.js
@@ -0,0 +1,16 @@
+const fs = require('fs')
+let cc = {}
+
+const after = (times, fn) => () => --times === 0 && fn()
+let newA = after(2, ()=> {
+  console.log(cc)
+})
+
+fs.readFile('name.txt', (err, data) => {
+  cc['name'] = data.toString()
+  newA()
+})
+fs.readFile('age.txt', (err, data) => {
+  cc['age'] = data.toString()
+  newA()
+})
\ No newline at end of file
diff --git a/0606/name.txt b/0606/name.txt
new file mode 100644
index 0000000..2652f5f
--- /dev/null
+++ b/0606/name.txt
@@ -0,0 +1 @@
+cc
\ No newline at end of file
diff --git a/0606/pormise2.js b/0606/pormise2.js
new file mode 100644
index 0000000..080a342
--- /dev/null
+++ b/0606/pormise2.js
@@ -0,0 +1,120 @@
+class MyPromise {
+  constructor(executor) {
+      // 初始属性值
+      this.status = 'pending';
+      this.value = undefined;
+      this.resolvedArr = [];
+      this.rejectedArr = [];
+
+      // 改变状态的函数
+      let changeStatus = (status, result) => {
+          if (this.status !== 'pending') return;
+          this.status = status;
+          this.value = result;
+          let arr = status === 'rejected' ? this.rejectedArr : this.resolvedArr;
+          arr.forEach(item => (typeof item === 'function' ? item(this.value) : null));
+      };
+      let resolve = result => {
+          if (this.resolvedArr.length > 0) {
+              changeStatus('resolved', result);
+              return;
+          }
+          let delayTimer = setTimeout(() => {
+              clearTimeout(delayTimer);
+              changeStatus('resolved', result);
+          }, 0);
+      };
+      let reject = reason => {
+          if (this.rejectedArr.length > 0) {
+              changeStatus('rejected', reason);
+              return;
+          }
+          let delayTimer = setTimeout(() => {
+              clearTimeout(delayTimer);
+              changeStatus('rejected', reason);
+          }, 0);
+      };
+
+      // 异常捕获处理
+      try {
+          executor(resolve, reject);
+      } catch (error) {
+          reject(error);
+      }
+  }
+
+  then(resolvedFn, rejectedFn) {
+      if (typeof resolvedFn !== 'function') {
+          resolvedFn = result => {
+              return result;
+          };
+      }
+      if (typeof rejectedFn !== 'function') {
+          rejectedFn = reason => {
+              // throw new Error(reason);
+              return new MyPromise((resolve, reject) => {
+                  reject(reason);
+              });
+          };
+      }
+
+      // then链：返回一个新的Promise实例
+      return new MyPromise((resolve, reject) => {
+          this.resolvedArr.push(() => {
+              try {
+                  let x = resolvedFn(this.value);
+                  x instanceof MyPromise ? x.then(resolve, reject) : resolve(x);
+              } catch (error) {
+                  reject(error);
+              }
+          });
+          this.rejectedArr.push(() => {
+              try {
+                  let x = rejectedFn(this.value);
+                  x instanceof MyPromise ? x.then(resolve, reject) : resolve(x);
+              } catch (error) {
+                  reject(error);
+              }
+          });
+      });
+  }
+
+  catch (rejectedFn) {
+      // catch(rejectedFn) === then(null,rejectedFn)
+      return this.then(null, rejectedFn);
+  }
+
+  /* 静态方法 */
+  static resolve(result) {
+      return new MyPromise(resolve => {
+          resolve(result);
+      });
+  }
+
+  static reject(reason) {
+      return new MyPromise((_, reject) => {
+          reject(reason);
+      });
+  }
+
+  static all(arr) {
+      return new MyPromise((resolve, reject) => {
+          let index = 0,
+              results = [];
+          for (let i = 0; i < arr.length; i++) {
+              let item = arr[i];
+              if (!(item instanceof MyPromise)) continue;
+              item.then(result => {
+                  index++;
+                  results[i] = result;
+                  if (index === arr.length) {
+                      resolve(results);
+                  }
+              }).catch(reason => {
+                  // 只要有一个失败，整体就是失败
+                  reject(reason);
+              });
+          }
+      });
+  }
+}
\ No newline at end of file
diff --git a/0606/promise.js b/0606/promise.js
new file mode 100644
index 0000000..2592b4f
--- /dev/null
+++ b/0606/promise.js
@@ -0,0 +1,201 @@
+const PENDING = 'pending'
+const RESOLVED = 'resolved'
+const REJECTED = 'rejected'
+const resolvePromise = (promise2, x, resolve, reject) => {
+  if (promise2 === x) {
+    // console.log('==')
+    return reject(new TypeError('不能返回自己'))
+  }
+  
+  if(x && typeof x === 'object' || typeof x === 'function') {
+    let called // 默认没有调用成功
+    try {
+      let then = x.then // 取then的时候可能会发生错误 例如getter
+      if(typeof then === 'function') {
+        then.call(x, y => {
+          // resolve(y)
+          // 递归解析promise
+          if(called) return // 防止多次调用
+          called = true
+          resolvePromise(promise2, y, resolve, reject)
+        },r => {
+          if(called) return
+          called = true
+          reject(r)
+        })
+      }
+    } catch (error) {
+      if(called) return
+      called = true
+      reject(error)
+    }
+  } else {
+    resolve(x)
+  }
+}
+class Promise {
+  constructor(excutor) { // excutor 立即执行的
+    this.state = PENDING
+    this.value = undefined
+    this.reason = undefined
+    this.onResolvedCallbacks = []
+    this.onRejectedCallbacks = []
+    const resolve = (value) => { //成功
+      if(value instanceof Promise) {
+        return value.then(resolve, reject)
+      }
+      if (this.state === PENDING) {
+        this.state = RESOLVED
+        this.value = value
+        this.onResolvedCallbacks.forEach(fn => fn())
+      }
+    }
+    const reject = (reason) => {
+      this.state = REJECTED
+      this.reason = reason
+      this.onRejectedCallbacks.forEach(fn => fn())
+    }
+    try {
+      excutor(resolve, reject) // 出错直接到reject
+    } catch (error) {
+      reject(error)
+    }
+  }
+
+  then(onResolved, onRejected) {
+    // 可选参数 穿透
+    onResolved = typeof onResolved === 'function' ? onResolved : value => value
+    onRejected = typeof onRejected === 'function' ? onRejected : err => {throw err}
+    // then 方法应该返回一个新的promise
+    let promise2 = new Promise((resolve, reject) => {
+      if (this.state === RESOLVED) {
+        // console.log('resolved')
+        setTimeout(() => {
+          try {
+            let res = onResolved(this.value)
+            // console.log(res)
+            resolvePromise(promise2, res, resolve, reject)
+          } catch (error) {
+            reject(error)
+          }
+        })
+      }
+      if (this.state === REJECTED) {
+        // console.log('rejected')
+        setTimeout(() => {
+          try {
+            let res = onRejected(this.reason)
+            resolvePromise(promise2, res, resolve, reject)
+          } catch (error) {
+            reject(error)
+          }
+        })
+      }
+      if (this.state === PENDING) {
+        // console.log('pending')
+        this.onResolvedCallbacks.push(() => {
+          // onResolved(this.value)
+          setTimeout(() => {
+            try {
+              let res = onResolved(this.value)
+              // console.log(res)
+              resolvePromise(promise2, res, resolve, reject)
+            } catch (error) {
+              reject(error)
+            }
+          })
+        })
+        this.onRejectedCallbacks.push(() => {
+          // onRejected(this.reason)
+          setTimeout(() => {
+            try {
+              let res = onRejected(this.reason)
+              resolvePromise(promise2, res, resolve, reject)
+            } catch (error) {
+              reject(error)
+            }
+          })
+        })
+      }
+    })
+    return promise2
+  }
+  catch(onRejected) {
+    return this.then(null, onRejected)
+  }
+  static resolve(value) {
+    return new Promise(resolve => {
+      resolve(value)
+    })
+  }
+  static reject(reason) {
+    return new Promise((resolve, reject) => {
+      reject(reason)
+    })
+  }
+  static all(promises) {
+    return new Promise((resolve, reject) => {
+      let index = 0, results = []
+      for(let i = 0; i< promises.length; i++) {
+        let item = promises[i]
+        if(item instanceof Promise) {
+          item.then(res => {
+            results[i] = res
+            index ++
+            if(index === promises.length) {
+              resolve(results)
+            }
+          }).catch(reason => {
+            reject(reason)
+          })
+        } else {
+            results[i] = item
+            index ++
+            if(index === promises.length) {
+              resolve(results)
+            }
+        }
+      }
+    })
+  }
+  static race(promises) {
+    return new Promise((resolve, reject) => {
+      promises.forEach(item => {
+        if(item instanceof Promise) {
+          item.then(res => resolve(res))
+        } else {
+          resolve(item)
+        }
+      })
+    })
+  }
+}
+
+module.exports = Promise
+
+/*
+    const handle = (cb, data) => {
+      try {
+        const res = cb(data)
+        res instanceof Promise  ? res.then(resolve, reject) : resolve(res)
+      } catch (error) {
+       reject(error)
+      }
+    }
+    if(this.state === RESOLVED) {
+     handle(onResolved, this.value)
+    }
+    if(this.state === REJECTED) {
+      handle(onRejected, this.reason)
+    }
+    if(this.state === PENDING){
+      this.onResolvedCallbacks.push(() => {
+        // onResolved(this.value)
+        handle(onResolved, this.value)
+      })
+      this.onRejectedCallbacks.push(() => {
+        // onRejected(this.reason)
+        handle(onRejected, this.reason)
+      })
+    }
+    */
\ No newline at end of file
diff --git a/0606/test.js b/0606/test.js
new file mode 100644
index 0000000..4e142c6
--- /dev/null
+++ b/0606/test.js
@@ -0,0 +1,24 @@
+// const Promise = require('./promise')
+
+
+let p = new Promise((resolve, reject) => {
+    setTimeout(() => {
+      resolve('hhh')
+    })
+})
+
+let p2 = new Promise(r => {
+  r('llll')
+})
+
+// p.then(() => {
+//   return 11
+// }).then(res => {
+//   return new Promise(a => {
+//     a(res+22)
+//   })
+// }).then(res => console.log(res), err=> console.log(err.message))
+
+// let p2= p.then(() => {return p2})
+// p2.then(res => {console.log('r',res)}, err => console.log(err))
+Promise.race([p,2,p2,1]).then(res => console.log(res))
\ No newline at end of file
diff --git a/better-scroll/1.js b/better-scroll/1.js
new file mode 100644
index 0000000..14269db
--- /dev/null
+++ b/better-scroll/1.js
@@ -0,0 +1,17 @@
+const CryptoJS = require('crypto-js')
+const fs = require('fs')
+
+const data = 'RzRaVE9PSldJVTNUSU4yQ0dNMkRHTUpXSVkzVENNWlpHTVlUR01aVEc0WkVJTlNGRzRaREdOQlRHVVpFSU1aVUc0WURNUkpUSEFaRUlNWlpHTTRUT01CVEdVWkVJTlpTRzRZVEdOUlRHRVpURU1aVkdNWVRHTVpUR1VaVFFOWlRHTTRET1JBPQ'
+let baseResult=CryptoJS.enc.Base64.parse(data)
+// var parsedWordArray = cr.enc.Base64.parse(data);
+var parsedStr = baseResult.toString(CryptoJS.enc.Utf8);
+console.log("parsed:",parsedStr);
+// console.log(baseResult)
+// fs.writeFile('./1.txt', baseResult, (err) => {
+//   if(err) {
+//     console.log(err)
+//   }
+// })
+
+// var test = CryptoJS.enc.Base64.parse("1ffffffff5a8ae57");
+// console.log(CryptoJS.enc.Base64.stringify(test));
\ No newline at end of file
diff --git a/better-scroll/1.txt b/better-scroll/1.txt
new file mode 100644
index 0000000..48a4376
--- /dev/null
+++ b/better-scroll/1.txt
@@ -0,0 +1 @@
+47345a544f4f4a5749553354494e3243474d3244474d4a5749593354434d5a5a474d5954474d5a5447345a45494e534647345a44474e425447555a45494d5a55473459444d524a5448415a45494d5a5a474d34544f4d425447555a45494e5a5347345954474e525447455a54454d5a56474d5954474d5a5447555a54514e5a54474d34444f52413d
\ No newline at end of file
diff --git a/better-scroll/package-lock.json b/better-scroll/package-lock.json
new file mode 100644
index 0000000..d5cdf9e
--- /dev/null
+++ b/better-scroll/package-lock.json
@@ -0,0 +1,23 @@
+{
+  "name": "better-scroll",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "crypto": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npm.taobao.org/crypto/download/crypto-1.0.1.tgz",
+      "integrity": "sha1-KvG3ytgXXSTIobB3glV5SiGAMDc="
+    },
+    "crypto-js": {
+      "version": "4.0.0",
+      "resolved": "https://registry.npm.taobao.org/crypto-js/download/crypto-js-4.0.0.tgz",
+      "integrity": "sha1-KQSrJnep0EKFai6i74DekuSjbcw="
+    },
+    "cryptojs": {
+      "version": "2.5.3",
+      "resolved": "https://registry.npm.taobao.org/cryptojs/download/cryptojs-2.5.3.tgz",
+      "integrity": "sha1-kJVH7PFbrEVuJ1RZs58u9F1/y7k="
+    }
+  }
+}
diff --git a/better-scroll/package.json b/better-scroll/package.json
new file mode 100644
index 0000000..a59daf5
--- /dev/null
+++ b/better-scroll/package.json
@@ -0,0 +1,17 @@
+{
+  "name": "better-scroll",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "crypto": "^1.0.1",
+    "crypto-js": "^4.0.0",
+    "cryptojs": "^2.5.3"
+  }
+}