Adds initial tests

components/header/back-button.js

@@ -13,9 +13,9 @@ export default function BackButtonHeader(props) {
         style={styles.accentCircle}
         left={props.middle - styles.accentCircle.width / 2}
       />
-      <NavigationArrow direction='left' {...props}/>
+      <NavigationArrow testID='backButton' direction='left' {...props}/>
       <View>
-        <Text style={styles.headerText}>
+        <Text style={styles.headerText} testID='pageTitle'>
           {props.title}
         </Text>
       </View>

components/header/cycle-day.js

@@ -14,7 +14,7 @@ export default function CycleDayHeader({ date, ...props }) {
     />
     <NavigationArrow direction='left' {...props}/>
     <View>
-      <Text style={styles.dateHeader}>
+      <Text style={styles.dateHeader} testID='cycleDayTitleDate'>
         {formatDate(date)}
       </Text>
       {props.cycleDayNumber &&

components/header/navigation-arrow.js

@@ -25,6 +25,7 @@ export default function NavigationArrow(props) {
     <TouchableOpacity
       style={[styles.navigationArrow, styles[iconPosition]]}
       onPress={pressHandler}
+      testID={props.testID}
     >
       <Icon
         name={iconName}

components/header/symptom-view.js

@@ -23,10 +23,10 @@ export default function SymptomViewHeader(props) {
         {...props}
       />
       <View>
-        <Text style={styles.dateHeader}>
+        <Text style={styles.dateHeader} testID='symptomViewTitleName'>
           {props.title}
         </Text>
-        <Text style={styles.cycleDayNumber}>
+        <Text style={styles.cycleDayNumber} testID='symptomViewTitleDate'>
           {formatDate(props.date)}
         </Text>
       </View >