fix: (getByText) more robust null/undefined check for text children (#239)

* fix: (getNodeByText) explicitly check if child is undefined or null

* test: Update getByText test cases

Author: hduprat

src/__tests__/__snapshots__/render.test.js.snap

@@ -57,6 +57,9 @@ exports[`debug 1`] = `
   >
     Second Text
   </Text>
+  <Text>
+    0
+  </Text>
 </View>"
 `;
 
@@ -117,6 +120,9 @@ exports[`debug changing component: bananaFresh button message should now be "fre
   >
     Second Text
   </Text>
+  <Text>
+    0
+  </Text>
 </View>"
 `;
 
@@ -162,6 +168,9 @@ exports[`debug: shallow 1`] = `
   >
     Second Text
   </Text>
+  <Text>
+    0
+  </Text>
 </View>"
 `;
 
@@ -209,6 +218,9 @@ exports[`debug: shallow with message 1`] = `
   >
     Second Text
   </Text>
+  <Text>
+    0
+  </Text>
 </View>"
 `;
 
@@ -271,6 +283,9 @@ exports[`debug: with message 1`] = `
   >
     Second Text
   </Text>
+  <Text>
+    0
+  </Text>
 </View>"
 `;
 

src/__tests__/render.test.js

@@ -51,6 +51,7 @@ class Banana extends React.Component<any, any> {
   };
 
   render() {
+    const test = 0;
     return (
       <View>
         <Text>Is the banana fresh?</Text>
@@ -72,6 +73,7 @@ class Banana extends React.Component<any, any> {
         </Button>
         <Text testID="duplicateText">First Text</Text>
         <Text testID="duplicateText">Second Text</Text>
+        <Text>{test}</Text>
       </View>
     );
   }
@@ -121,7 +123,7 @@ test('getByName, queryByName', () => {
 
   expect(bananaFresh.props.children).toBe('not fresh');
   expect(() => getByName('InExistent')).toThrow('No instances found');
-  expect(() => getByName(Text)).toThrow('Expected 1 but found 5');
+  expect(() => getByName(Text)).toThrow('Expected 1 but found 6');
 
   expect(queryByName('Button')).toBe(button);
   expect(queryByName('InExistent')).toBeNull();
@@ -165,9 +167,12 @@ test('getByText, queryByText', () => {
   expect(sameButton.props.children).toBe('not fresh');
   expect(() => getByText('InExistent')).toThrow('No instances found');
 
+  const zeroText = getByText('0');
+
   expect(queryByText(/change/i)).toBe(button);
   expect(queryByText('InExistent')).toBeNull();
   expect(() => queryByText(/fresh/)).toThrow('Expected 1 but found 3');
+  expect(queryByText('0')).toBe(zeroText);
 });
 
 test('getByText, queryByText with children as Array', () => {

src/helpers/getByAPI.js

@@ -22,8 +22,8 @@ const getNodeByText = (node, text) => {
     if (isTextComponent) {
       const textChildren = React.Children.map(
         node.props.children,
-        // In some cases child might be undefined
-        child => (child ? child.toString() : '')
+        // In some cases child might be undefined or null
+        child => (child !== undefined && child !== null ? child.toString() : '')
       );
       if (textChildren) {
         const textToTest = textChildren.join('');