feat(util): add mutex module

src/__tests__/modules/util.test.ts

@@ -11,6 +11,7 @@ import { score, positions } from '../../util/fzy'
 import { getHiglights } from '../../util/highlight'
 import { score as matchScore } from '../../util/match'
 import { mixin } from '../../util/object'
+import { Mutex } from '../../util/mutex'
 import { indexOf, resolveVariables } from '../../util/string'
 import helper from '../helper'
 import { ansiparse } from '../../util/ansiparse'
@@ -212,3 +213,44 @@ describe('ansiparse', () => {
     })
   })
 })
+
+describe('Mutex', () => {
+  test('mutex run in serial', async () => {
+    let lastTs: number
+    let fn = () => {
+      return new Promise(resolve => {
+        if (lastTs) {
+          let dt = Date.now() - lastTs
+          expect(dt).toBeGreaterThanOrEqual(300)
+        }
+        lastTs = Date.now()
+        setTimeout(() => {
+          resolve()
+        }, 300)
+      })
+    }
+    let mutex = new Mutex()
+    await Promise.all([
+      mutex.use(fn),
+      mutex.use(fn),
+      mutex.use(fn)
+    ])
+  })
+
+  test('mutex run after job finish', async () => {
+    let count = 0
+    let fn = () => {
+      return new Promise(resolve => {
+        count = count + 1
+        setTimeout(() => {
+          resolve()
+        }, 100)
+      })
+    }
+    let mutex = new Mutex()
+    await mutex.use(fn)
+    await helper.wait(10)
+    await mutex.use(fn)
+    expect(count).toBe(2)
+  })
+})

src/util/mutex.ts

@@ -0,0 +1,49 @@
+export class Mutex {
+  private tasks: (() => void)[] = []
+  private count = 1
+
+  private sched(): void {
+    if (this.count > 0 && this.tasks.length > 0) {
+      this.count--
+      let next = this.tasks.shift()
+      next()
+    }
+  }
+
+  public get busy(): boolean {
+    return this.count == 0
+  }
+
+  // tslint:disable-next-line: typedef
+  public acquire() {
+    return new Promise<() => void>(res => {
+      let task = () => {
+        let released = false
+        res(() => {
+          if (!released) {
+            released = true
+            this.count++
+            this.sched()
+          }
+        })
+      }
+      this.tasks.push(task)
+      process.nextTick(this.sched.bind(this))
+    })
+  }
+
+  public use<T>(f: () => Promise<T>): Promise<T> {
+    return this.acquire()
+      .then(release => {
+        return f()
+          .then(res => {
+            release()
+            return res
+          })
+          .catch(err => {
+            release()
+            throw err
+          })
+      })
+  }
+}

src/workspace.ts

@@ -29,6 +29,7 @@ import { disposeAll, getKeymapModifier, isDocumentEdit, mkdirp, runCommand, wait
 import { score } from './util/match'
 import { getChangedFromEdits } from './util/position'
 import { byteIndex, byteLength } from './util/string'
+import { Mutex } from './util/mutex'
 import Watchman from './watchman'
 import rimraf from 'rimraf'
 import uuid = require('uuid/v1')
@@ -45,6 +46,7 @@ export class Workspace implements IWorkspace {
   public readonly version: string
   public readonly keymaps: Map<string, [Function, boolean]> = new Map()
   public bufnr: number
+  private mutex = new Mutex()
   private resolver: Resolver = new Resolver()
   private rootPatterns: Map<string, string[]> = new Map()
   private _workspaceFolders: WorkspaceFolder[] = []
@@ -55,7 +57,6 @@ export class Workspace implements IWorkspace {
   private _env: Env
   private _root: string
   private _cwd = process.cwd()
-  private _blocking = false
   private _initialized = false
   private _attached = false
   private buffers: Map<number, Document> = new Map()
@@ -319,8 +320,7 @@ export class Workspace implements IWorkspace {
       if (!res) return
       fs.mkdirSync(dir)
     }
-    let uri = URI.file(path.join(dir, 'coc-settings.json')).toString()
-    await this.jumpTo(uri)
+    await this.jumpTo(URI.file(path.join(dir, 'coc-settings.json')).toString())
   }
 
   public get textDocuments(): TextDocument[] {
@@ -724,7 +724,7 @@ export class Workspace implements IWorkspace {
    * Show message in vim.
    */
   public showMessage(msg: string, identify: MsgTypes = 'more'): void {
-    if (this._blocking || !this.nvim) return
+    if (this.mutex.busy || !this.nvim) return
     let { messageLevel } = this
     let method = process.env.VIM_NODE_RPC == '1' ? 'callTimer' : 'call'
     let hl = 'Error'
@@ -1060,22 +1060,34 @@ export class Workspace implements IWorkspace {
    * Show quickpick
    */
   public async showQuickpick(items: string[], placeholder = 'Choose by number'): Promise<number> {
-    let title = placeholder + ':'
-    items = items.map((s, idx) => `${idx + 1}. ${s}`)
-    let res = await this.nvim.callAsync('coc#util#quickpick', [title, items])
-    let n = parseInt(res, 10)
-    if (isNaN(n) || n <= 0 || n > items.length) return -1
-    return n - 1
+    let release = await this.mutex.acquire()
+    try {
+      let title = placeholder + ':'
+      items = items.map((s, idx) => `${idx + 1}. ${s}`)
+      let res = await this.nvim.callAsync('coc#util#quickpick', [title, items])
+      release()
+      let n = parseInt(res, 10)
+      if (isNaN(n) || n <= 0 || n > items.length) return -1
+      return n - 1
+    } catch (e) {
+      release()
+      return -1
+    }
   }
 
   /**
    * Prompt for confirm action.
    */
   public async showPrompt(title: string): Promise<boolean> {
-    this._blocking = true
-    let res = await this.nvim.callAsync('coc#util#with_callback', ['coc#util#prompt_confirm', [title]])
-    this._blocking = false
-    return res == 1
+    let release = await this.mutex.acquire()
+    try {
+      let res = await this.nvim.callAsync('coc#util#with_callback', ['coc#util#prompt_confirm', [title]])
+      release()
+      return res == 1
+    } catch (e) {
+      release()
+      return false
+    }
   }
 
   public async callAsync<T>(method: string, args: any[]): Promise<T> {
@@ -1495,7 +1507,7 @@ augroup end`
   }
 
   private async checkBuffer(bufnr: number): Promise<void> {
-    if (this._disposed) return
+    if (this._disposed || !bufnr) return
     let doc = this.getDocument(bufnr)
     if (!doc && !this.creatingSources.has(bufnr)) await this.onBufCreate(bufnr)
   }