fix(setFormikInitialValue): do not override initial values passed from formik

Fixes #8

Author: Almouro

src/__tests__/setFormikInitialValue.js

@@ -8,14 +8,22 @@ import { setFormikInitialValue } from "../..";
 
 console.error = jest.fn();
 
-const setFieldValue = jest.fn();
+let setFieldValue;
+let Input;
 
-const withFormikMock = withContext({ formik: PropTypes.object }, () => ({
-  formik: {
-    setFieldValue
-  }
-}));
-const Input = compose(withFormikMock, setFormikInitialValue)(TextInput);
+beforeEach(() => {
+  setFieldValue = jest.fn();
+
+  const withFormikMock = withContext({ formik: PropTypes.object }, () => ({
+    formik: {
+      setFieldValue,
+      values: {
+        "this input has been set by formik": "set value"
+      }
+    }
+  }));
+  Input = compose(withFormikMock, setFormikInitialValue)(TextInput);
+});
 
 describe("setFormikInitialValue", () => {
   it("sets the initial value to ''", () => {
@@ -27,4 +35,9 @@ describe("setFormikInitialValue", () => {
     const wrapper = mount(<Input name="inputName" someProp="someValue" />);
     expect(wrapper.find(TextInput).props().someProp).toEqual("someValue");
   });
+
+  it("does not set initial value if set by formik, e.g. with initial values", () => {
+    const wrapper = mount(<Input name="this input has been set by formik" />);
+    expect(setFieldValue).not.toBeCalled()
+  });
 });

src/setFormikInitialValue.js

@@ -1,12 +1,17 @@
 import React from "react";
 import { compose, mapProps } from "recompose";
+import { has } from "lodash";
 import withFormik from "./withFormik";
 
 const setFormikInitialValue = WrappedInput => {
   return class WithFocusProp extends React.PureComponent {
     constructor(props) {
       super(props);
-      props.formik.setFieldValue(props.name, "");
+
+      const { formik, name } = props;
+      if (!has(formik.values, name)) {
+        formik.setFieldValue(name, "");
+      }
     }
 
     render() {