feat(osx): support multi screenshot for multi screens on mac (#101)

* screenshot support multi screens

* ignore files

* link and fix delete file error

* examples

* remove unused

* lint

Author: 0xganz

.gitignore

@@ -2,3 +2,5 @@ node_modules
 out.jpg
 *.exe
 *.log
+*.png
+package-lock.json

.vscode/launch.json

@@ -0,0 +1,19 @@
+{
+    // 使用 IntelliSense 了解相关属性。
+    // 悬停以查看现有属性的描述。
+    // 欲了解更多信息，请访问: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "debug one File",
+            "args": [
+                // "--enable-logging"
+            ],
+            "console": "integratedTerminal",
+            "program": "${file}",
+            "protocol": "inspector"
+        }
+    ]
+}

example.js renamed to examples/example.js

@@ -6,10 +6,8 @@ screenshot().then((img) => {
     if (err) {
       throw err
     }
-
     console.log('written to out.jpg')
   })
+}).catch((err) => {
+  throw err
 })
-  .catch((err) => {
-    throw err
-  })

examples/multiScreens.js

@@ -0,0 +1,29 @@
+const path = require('path')
+const screenshot = require('..')
+
+screenshot.listDisplays()
+  .then((displays) => {
+    console.log(displays)
+    for (let index = 0; index < displays.length; index++) {
+      const display = displays[index]
+      const imgpath = path.join(__dirname, Date.now() + '_' + index + '.png')
+      screenshot({ screen: display.id, filename: imgpath }).then((imgpath) => {
+        console.log(imgpath)
+      }).catch(err => {
+        console.error(err)
+      })
+    }
+  })
+
+screenshot.listDisplays()
+  .then((displays) => {
+    console.log(displays)
+    for (let index = 0; index < displays.length; index++) {
+      const display = displays[index]
+      screenshot({ screen: display.id }).then((imgbuf) => {
+        console.log(imgbuf)
+      }).catch(err => {
+        console.error(err)
+      })
+    }
+  })

lib/darwin/index.js

@@ -26,20 +26,18 @@ function darwinSnapshot (options = {}) {
       .fill(null)
       .map(() => temp.path({ suffix }))
 
-    let pathsToDelete = tmpPaths
+    let pathsToDelete = []
     if (options.filename) {
       tmpPaths[displayId] = filename
-      pathsToDelete = tmpPaths.slice(0, -1)
     }
+    pathsToDelete = tmpPaths.slice(displayId)
 
-    exec('screencapture -x -t ' + suffix.slice(1) + ' ' + tmpPaths.join(' '),
+    exec('screencapture' + ' -D ' + (displayId + 1) + ' ' + ' -x -t ' + suffix.slice(1) + ' ' + tmpPaths.slice(displayId).join(' '),
       function (err, stdOut) {
         if (err) {
           return reject(err)
         } else if (options.filename) {
-          Promise.all(pathsToDelete.map(unlinkP))
-            .then(() => resolve(path.resolve(options.filename)))
-            .catch((err) => reject(err))
+          resolve(path.resolve(options.filename))
         } else {
           fs.readFile(tmpPaths[displayId], function (err, img) {
             if (err) {
@@ -141,23 +139,26 @@ function parseDisplaysOutput (output) {
     return []
   }
 
-  const firstGpuKey = Object.keys(tree['Graphics/Displays'])[0]
-  if (!firstGpuKey) {
+  const firstGpuKeys = Object.keys(tree['Graphics/Displays'])
+  if (!firstGpuKeys || firstGpuKeys.length <= 0) {
     return []
   }
 
-  const firstGpu = tree['Graphics/Displays'][firstGpuKey]
-  if (!firstGpu) {
-    return []
-  }
+  let displayinfos = []
 
-  const displays = Object.entries(firstGpu['Displays'])
-    .map(([name, props]) => {
-      const primary = props['Main Display'] === 'Yes'
-      return { name, primary }
-    })
+  firstGpuKeys.forEach(gpukey => {
+    const gpu = tree['Graphics/Displays'][gpukey]
+    if (gpu.Displays) {
+      const temp = Object.entries(gpu.Displays)
+        .map(([name, props]) => {
+          const primary = props['Main Display'] === 'Yes'
+          return { name, primary }
+        })
+      displayinfos = displayinfos.concat(temp)
+    }
+  })
 
-  return addId(movePrimaryToHead(displays))
+  return addId(movePrimaryToHead(displayinfos))
 }
 
 function listDisplays () {