move addon package transforms back to method

Author: Ruslan Hrabovyi

ts/blueprints/ember-cli-typescript/index.js

@@ -121,16 +121,7 @@ module.exports = {
 
   beforeInstall() {
     if (this.project.isEmberCLIAddon()) {
-      let pkg = readPackage(this.project);
-
-      this._installPrecompilationHooks(pkg);
-
-      if (pkg.devDependencies['ember-cli-typescript']) {
-        pkg.dependencies['ember-cli-typescript'] = pkg.devDependencies['ember-cli-typescript'];
-        delete pkg.devDependencies['ember-cli-typescript'];
-      }
-
-      writePackage(this.project, pkg);
+      this._transformAddonPackage();
     }
 
     let packages = [
@@ -184,11 +175,23 @@ module.exports = {
     return this.project.isModuleUnification && this.project.isModuleUnification();
   },
 
-  _installPrecompilationHooks(pkg) {
-      // Really `prepack` and `postpack` would be ideal, but yarn doesn't execute those when publishing
-      this._addScript(pkg.scripts, 'prepublishOnly', 'ember ts:precompile');
-      this._addScript(pkg.scripts, 'postpublish', 'ember ts:clean');
+  _transformAddonPackage() {
+    const pkgPath = `${this.project.root}/package.json`;
+
+    let pkg = JSON.parse(fs.readFileSync(pkgPath, 'utf-8'));
+
+    // Really `prepack` and `postpack` would be ideal, but yarn doesn't execute those when publishing
+    this._addScript(pkg.scripts, 'prepublishOnly', 'ember ts:precompile');
+    this._addScript(pkg.scripts, 'postpublish', 'ember ts:clean');
+
+    // avoid being placed in devDependencies
+    const name = 'ember-cli-typescript';
+    if (pkg.devDependencies[name]) {
+      pkg.dependencies[name] = pkg.devDependencies[name];
+      delete pkg.devDependencies[name];
+    }
 
+    fs.writeFileSync(pkgPath, JSON.stringify(pkg, null, 2) + '\n');
   },
 
   _addScript(scripts, type, script) {
@@ -209,15 +212,3 @@ module.exports = {
     }
   },
 };
-
-const packagePath = (project) => `${project.root}/package.json`;
-
-function readPackage(project) {
-  const path = packagePath(project)
-
-  return JSON.parse(fs.readFileSync(path, 'utf-8'));
-}
-
-function writePackage(project, pkg) {
-  fs.writeFileSync(packagePath(project), JSON.stringify(pkg, null, 2) + '\n');
-}