ejected create-react-app

config/jest/cssTransform.js

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+'use strict';
+
+// This is a custom Jest transformer turning style imports into empty objects.
+// http://facebook.github.io/jest/docs/tutorial-webpack.html
+
+module.exports = {
+  process() {
+    return 'module.exports = {};';
+  },
+  getCacheKey() {
+    // The output is always the same.
+    return 'cssTransform';
+  },
+};

config/jest/fileTransform.js

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+'use strict';
+
+const path = require('path');
+
+// This is a custom Jest transformer turning file imports into filenames.
+// http://facebook.github.io/jest/docs/tutorial-webpack.html
+
+module.exports = {
+  process(src, filename) {
+    return `module.exports = ${JSON.stringify(path.basename(filename))};`;
+  },
+};

config/jest/typescriptTransform.js

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+// Copyright 2004-present Facebook. All Rights Reserved.
+
+'use strict';
+
+const fs = require('fs');
+const tsc = require('typescript');
+const tsconfigPath = require('app-root-path').resolve('/tsconfig.json');
+
+let compilerConfig = {
+  module: tsc.ModuleKind.CommonJS,
+  jsx: tsc.JsxEmit.React,
+}
+
+if (fs.existsSync(tsconfigPath)) {
+  try {
+    const tsconfig = require(tsconfigPath);
+
+    if (tsconfig && tsconfig.compilerOptions) {
+      compilerConfig = tsconfig.compilerOptions;
+    }
+  } catch (e) { /* Do nothing - default is set */ }
+}
+
+module.exports = {
+  process(src, path) {
+    if (path.endsWith('.ts') || path.endsWith('.tsx')) {
+      return tsc.transpile(
+        src,
+        compilerConfig,
+        path, []
+      );
+    }
+    return src;
+  },
+};