refactor(transformers): move transformers to transformers dir (#455)

BREAKING CHANGE:
One is using all `jest-preset-angular` transformers should change jest config to have:
```
// jest.config.js
const customTransformers = require('./build/transformers');

module.exports = {
     // [...]
     globals: {
        'ts-jest': {
            tsConfig: '<rootDir>/tsconfig.spec.json',
            stringifyContentPathRegex: '\\.html$',
            astTransformers: {
               before: customTransformers,
            },
         },
     },
}
```

One is using one of `jest-preset-angular` transformers should change jest config to have:
```
// jest.config.js
module.exports = {
     // [...]
     globals: {
        'ts-jest': {
            tsConfig: '<rootDir>/tsconfig.spec.json',
            stringifyContentPathRegex: '\\.html$',
            astTransformers: {
               before: [
                  'jest-preset-angular/build/transformers/inline-files'
               ],
            },
         },
     },
}
```
or
```
// package.json
{
     "jest" {
         // [...]
         "globals": {
              "ts-jest": {
                   "tsConfig": "<rootDir>/tsconfig.spec.json",
                   "stringifyContentPathRegex": "\\.html$",
                   "astTransformers": {
                        "before": [
                            "jest-preset-angular/build/transformers/inline-files"
                        ]
                   }
              }
         }
     }
}
```

src/__tests__/__snapshots__/StripStylesTransformer.test.ts.snap → src/__tests__/__snapshots__/strip-styles.test.ts.snap

@@ -1,14 +1,5 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`inlining template and stripping styles should not transform styles outside decorator 1`] = `
-"var assignmentsToNotBeTransformed = {
-    styles: [{
-            color: 'red'
-        }]
-};
-"
-`;
-
 exports[`inlining template and stripping styles should not strip styleUrls assignment 1`] = `
 "\\"use strict\\";
 var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {

src/__tests__/InlineFilesTransformer.test.ts → src/__tests__/inline-files.test.ts

@@ -5,7 +5,7 @@
  */
 
 import * as tsc from 'typescript';
-import * as transformer from '../InlineFilesTransformer';
+import * as transformer from '../transformers/inline-files';
 
 const CODE_WITH_TEMPLATE_URL = `
   import { Component } from '@angular/core';

src/__tests__/StripStylesTransformer.test.ts → src/__tests__/strip-styles.test.ts

@@ -5,7 +5,7 @@
  */
 
 import * as tsc from 'typescript';
-import * as transformer from '../StripStylesTransformer';
+import * as transformer from '../transformers/strip-styles';
 
 const CODE_WITH_STYLES_AND_OTHER_ASSIGNMENTS = `
   import { Component } from '@angular/core';

src/jest-preset.js

@@ -1,15 +1,13 @@
 const snapshotSerializers = require('./build/serializers');
+const customTransformers = require('./build/transformers');
 
 module.exports = {
   globals: {
     'ts-jest': {
       tsConfig: '<rootDir>/tsconfig.spec.json',
       stringifyContentPathRegex: '\\.html$',
       astTransformers: {
-        before: [
-          'jest-preset-angular/build/InlineFilesTransformer',
-          'jest-preset-angular/build/StripStylesTransformer',
-        ],
+        before: customTransformers,
       },
     },
   },

src/transformers/index.ts

@@ -0,0 +1 @@
+export = ['jest-preset-angular/build/transformers/inline-files', 'jest-preset-angular/build/transformers/strip-styles'];

src/InlineFilesTransformer.ts → src/transformers/inline-files.ts

@@ -32,7 +32,7 @@ import type {
   PropertyAssignment,
   LiteralLikeNode,
 } from 'typescript';
-import { getCreateStringLiteral, ConfigSet } from './TransformUtils';
+import { getCreateStringLiteral, ConfigSet } from './transform-utils';
 
 // replace original ts-jest ConfigSet with this simple interface, as it would require
 // jest-preset-angular to add several babel devDependencies to get the other types

src/StripStylesTransformer.ts → src/transformers/strip-styles.ts

@@ -34,7 +34,7 @@ import type {
   CallExpression,
   ObjectLiteralExpression,
 } from 'typescript';
-import type { ConfigSet } from './TransformUtils';
+import type { ConfigSet } from './transform-utils';
 
 /** Angular component decorator Styles property name */
 const STYLES = 'styles';

tsconfig.json

@@ -13,6 +13,6 @@
     "target": "es2015",
     "module": "CommonJS",
     "lib": ["esnext", "dom"],
-    "types": ["node"]
+    "types": ["node", "jest"]
   }
 }

tsconfig.spec.json

@@ -1,8 +1,7 @@
 {
   "extends": "./tsconfig.json",
   "compilerOptions": {
-    "target": "ES5",
-    "types": ["jest", "node"]
+    "target": "ES5"
   },
   "include": [] // boost test's speed trick
 }