Fixes: #3343 TextUtils.isEmpty creates problems when unit testing with Mockito (#3344)

* TextUtils: add mock textUtils for tests

* TextUtils: add more methods to mock for testing

* UploadControllerTest: fix the test resulting travis ci to fail

Author: kbhardwaj123

app/src/test/java/android/text/TextUtils.java

@@ -0,0 +1,82 @@
+package android.text;
+
+
+import androidx.annotation.Nullable;
+
+/**
+ * This Class Mocks TextUtils for the purpose of testing.
+ * NOTE: This class would not change the function of the TextUtils used in app
+ * it onlt mocks it for the unit tests
+ *
+ */
+public class TextUtils {
+    /**
+     * mocks TextUtils.isEmpty
+     */
+    public static boolean isEmpty(@Nullable CharSequence str) {
+        return str == null || str.length() == 0;
+    }
+
+    /**
+     * mocks TextUtils.equals
+     */
+    public static boolean equals(CharSequence a, CharSequence b) {
+        if (a == b) return true;
+        int length;
+        if (a != null && b != null && (length = a.length()) == b.length()) {
+            if (a instanceof String && b instanceof String) {
+                return a.equals(b);
+            } else {
+                for (int i = 0; i < length; i++) {
+                    if (a.charAt(i) != b.charAt(i)) return false;
+                }
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * mocks TextUtils.isDigitsOnly
+     */
+    public static boolean isDigitsOnly(CharSequence str) {
+        final int len = str.length();
+        for (int cp, i = 0; i < len; i += Character.charCount(cp)) {
+            cp = Character.codePointAt(str, i);
+            if (!Character.isDigit(cp)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * mocks TextUtils.isNewline
+     */
+    private static boolean isNewline(int codePoint) {
+        int type = Character.getType(codePoint);
+        return type == Character.PARAGRAPH_SEPARATOR || type == Character.LINE_SEPARATOR
+                || codePoint == 10;
+    }
+
+    /**
+     * Returns whether the given CharSequence contains any printable characters.
+     */
+    public static boolean isGraphic(CharSequence str) {
+        final int len = str.length();
+        for (int cp, i=0; i<len; i+=Character.charCount(cp)) {
+            cp = Character.codePointAt(str, i);
+            int gc = Character.getType(cp);
+            if (gc != Character.CONTROL
+                    && gc != Character.FORMAT
+                    && gc != Character.SURROGATE
+                    && gc != Character.UNASSIGNED
+                    && gc != Character.LINE_SEPARATOR
+                    && gc != Character.PARAGRAPH_SEPARATOR
+                    && gc != Character.SPACE_SEPARATOR) {
+                return true;
+            }
+        }
+        return false;
+    }
+}

app/src/test/kotlin/fr/free/nrw/commons/upload/UploadControllerTest.kt

@@ -49,6 +49,7 @@ class UploadControllerTest {
     @Test
     fun startUpload() {
         val contribution = mock(Contribution::class.java)
+        `when`(contribution.getCreator()).thenReturn("Creator")
         uploadController!!.startUpload(contribution)
     }
 }