public void testFilter() {
// Define the variables
CharSequence source;
SpannableStringBuilder dest;
// Constructor to create a LengthFilter
LengthFilter lengthFilter = new LengthFilter(10);
InputFilter[] filters = {lengthFilter};
// filter() implicitly invoked. If the total length > filter length, the filter will
// cut off the source CharSequence from beginning to fit the filter length.
source = "abc";
dest = new SpannableStringBuilder("abcdefgh");
dest.setFilters(filters);
dest.insert(1, source);
String expectedString1 = "aabbcdefgh";
assertEquals(expectedString1, dest.toString());
dest.replace(5, 8, source);
String expectedString2 = "aabbcabcgh";
assertEquals(expectedString2, dest.toString());
dest.delete(1, 3);
String expectedString3 = "abcabcgh";
assertEquals(expectedString3, dest.toString());
// filter() explicitly invoked
dest = new SpannableStringBuilder("abcdefgh");
CharSequence beforeFilterSource = "TestLengthFilter";
String expectedAfterFilter = "TestLength";
CharSequence actualAfterFilter =
lengthFilter.filter(
beforeFilterSource, 0, beforeFilterSource.length(), dest, 0, dest.length());
assertEquals(expectedAfterFilter, actualAfterFilter);
}
