hide readResult method (#131)

js/preload/preloadMain.js

@@ -107,7 +107,7 @@ function createAPI() {
          * provides api to allow user to capture portion of screen, see api
          * details in screenSnipper/ScreenSnippet.js
          */
-        ScreenSnippet: remote.require('./screenSnippet/ScreenSnippet.js'),
+        ScreenSnippet: remote.require('./screenSnippet/ScreenSnippet.js').ScreenSnippet,
 
         /**
          * Brings window forward and gives focus.

js/screenSnippet/ScreenSnippet.js

@@ -77,15 +77,17 @@ class ScreenSnippet {
                     // processs was killed, just resolve with no data.
                     resolve();
                 } else {
-                    this._readResult(outputFileName, resolve, reject, error);
+                    readResult.call(this, outputFileName, resolve, reject, error);
                 }
             });
         });
     }
+}
 
-    // private methods below here
-
-    _readResult(outputFileName, resolve, reject, childProcessErr) {
+// this function was moved outside of class since class is exposed to web
+// client via preload API, we do NOT want web client to be able to call this
+// method - then they could read any file on the disk!
+function readResult(outputFileName, resolve, reject, childProcessErr) {
     fs.readFile(outputFileName, (readErr, data) => {
         if (readErr) {
             let returnErr;
@@ -93,10 +95,10 @@ class ScreenSnippet {
                 // no such file exists, user likely aborted
                 // creating snippet. also include any error when
                 // creating child process.
-                    returnErr = this._createWarn('file does not exist ' +
+                returnErr = createWarn('file does not exist ' +
                     childProcessErr);
             } else {
-                    returnErr = this._createError(readErr + ',' +
+                returnErr = createError(readErr + ',' +
                     childProcessErr);
             }
 
@@ -105,7 +107,7 @@ class ScreenSnippet {
         }
 
         if (!data) {
-                reject(this._createWarn('no file data provided'));
+            reject(createWarn('no file data provided'));
             return;
         }
 
@@ -117,7 +119,7 @@ class ScreenSnippet {
                 data: output
             });
         } catch (error) {
-                reject(this._createError(error));
+            reject(createError(error));
         }
         finally {
             // remove tmp file (async)
@@ -131,22 +133,24 @@ class ScreenSnippet {
             });
         }
     });
+}
 
-    }
-
-    /* eslint-disable class-methods-use-this */
-    _createError(msg) {
+/* eslint-disable class-methods-use-this */
+function createError(msg) {
     var err = new Error(msg);
     err.type = 'ERROR';
     return err;
-    }
+}
 
-    _createWarn(msg) {
+function createWarn(msg) {
     var err = new Error(msg);
     err.type = 'WARN';
     return err;
-    }
-    /* eslint-enable class-methods-use-this */
 }
+/* eslint-enable class-methods-use-this */
 
-module.exports = ScreenSnippet;
+module.exports = {
+    ScreenSnippet: ScreenSnippet,
+    // note: readResult only exposed for testing purposes
+    readResult: readResult
+}

package.json

@@ -19,7 +19,7 @@
     "prebuild": "npm run lint && npm run test && npm run browserify-preload",
     "rebuild": "electron-rebuild -f",
     "lint": "eslint --ext .js js/",
-    "test": "jest --testPathPattern test",
+    "test": "jest --verbose --testPathPattern test",
     "browserify-preload": "browserify -o js/preload/_preloadMain.js -x electron --insert-global-vars=__filename,__dirname js/preload/preloadMain.js"
   },
   "jest": {

tests/ScreenSnippet.test.js

@@ -1,5 +1,5 @@
 
-const ScreenSnippet = require('../js/screenSnippet/ScreenSnippet.js');
+const { ScreenSnippet, readResult } = require('../js/screenSnippet/ScreenSnippet.js');
 const path = require('path');
 const fs = require('fs');
 const os = require('os');
@@ -71,8 +71,7 @@ describe('Tests for ScreenSnippet', function() {
 
         it('should remove output file after completed', function(done) {
             createTestFile(function(testfileName) {
-                let s = new ScreenSnippet();
-                s._readResult(testfileName, resolve);
+                readResult(testfileName, resolve);
 
                 function resolve() {
                     // should be long enough before file
@@ -88,9 +87,8 @@ describe('Tests for ScreenSnippet', function() {
     });
 
     it('should fail if output file does not exist', function(done) {
-        let s = new ScreenSnippet();
-        let nonExistentFile = 'bogus.jpeg'
-        s._readResult(nonExistentFile, resolve, reject);
+        let nonExistentFile = 'bogus.jpeg';
+        readResult(nonExistentFile, resolve, reject);
 
         function resolve() {
             // shouldn't get here