WebPack builds for improved loading times (VSCodeVim#3889)

Fixes VSCodeVim#3127

.travis.yml

@@ -38,7 +38,8 @@ script:
     echo "Prettier Failed. Run `gulp forceprettier` and commit changes to resolve.";
     exit 1;
   fi
-- npm run build
+- gulp build
+- gulp prepare-test
 - npm test
 
 before_deploy:

.vscodeignore

@@ -9,4 +9,9 @@ typings/**
 **/*.map
 .github_changelog_generator
 .gitignore
-*.yml
+*.yml
+# Not needed, due to webpack
+node_modules/
+src/
+tsconfig.json
+webpack.config.js

gulpfile.js

@@ -7,7 +7,9 @@ var gulp = require('gulp'),
   ts = require('gulp-typescript'),
   PluginError = require('plugin-error'),
   minimist = require('minimist'),
-  path = require('path');
+  path = require('path'),
+  webpack_stream = require('webpack-stream'),
+  webpack_config = require('./webpack.config.js');
 
 const exec = require('child_process').exec;
 const spawn = require('child_process').spawn;
@@ -126,6 +128,10 @@ function updateVersion(done) {
     });
 }
 
+function copyPackageJson() {
+  return gulp.src('./package.json').pipe(gulp.dest('out'));
+}
+
 gulp.task('tsc', function() {
   var isError = false;
 
@@ -146,6 +152,13 @@ gulp.task('tsc', function() {
     .pipe(gulp.dest('out'));
 });
 
+gulp.task('webpack', function() {
+  return gulp
+    .src('./extension.ts')
+    .pipe(webpack_stream(webpack_config))
+    .pipe(gulp.dest('out'));
+});
+
 gulp.task('tslint', function() {
   const program = require('tslint').Linter.createProgram('./tsconfig.json');
   return gulp
@@ -177,7 +190,7 @@ gulp.task('commit-hash', function(done) {
 });
 
 // test
-gulp.task('test', function(done) {
+gulp.task('run-test', function(done) {
   // the flag --grep takes js regex as a string and filters by test and test suite names
   var knownOptions = {
     string: 'grep',
@@ -228,7 +241,9 @@ gulp.task('test', function(done) {
   });
 });
 
-gulp.task('build', gulp.series('prettier', gulp.parallel('tsc', 'tslint'), 'commit-hash'));
+gulp.task('build', gulp.series('prettier', gulp.parallel('webpack', 'tslint'), 'commit-hash'));
+gulp.task('prepare-test', gulp.parallel('tsc', copyPackageJson));
+gulp.task('test', gulp.series('prepare-test', 'run-test'));
 gulp.task('changelog', gulp.series(validateArgs, createChangelog));
 gulp.task(
   'release',