import org.gradle.api.Transformer;
import org.gradle.internal.SystemProperties;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.Reader;

public class LineFilter extends Reader {
    private static enum State {
        NORMAL,
        SKIP_LINE,
        EOF
    };

    private final Transformer<String, String> transformer;
    private String transformedLine;

        def input = new StringReader("")
        def lineCount = 1
        def filter = new LineFilter(input, { "${lineCount++} - $it" as String })

        assertThat(filter.text, equalTo(""))
    }

    @Test void testEmptyLinesWithTrailingEOL() {
        def input = new StringReader("\n\n")
        def lineCount = 1
        def filter = new LineFilter(input, { "${lineCount++} - $it" as String })

        transformers.add(new Transformer<Reader, Reader>() {
            @Override
            public Reader transform(Reader reader) {
                return new LineFilter(reader, transformer);
            }
        });
    }

    public void add(final Closure closure) {
        add(new ClosureBackedTransformer(closure));
    }

    public void canAddLineFilterReaderToEndOfChain() {
        filterChain.add(TestUtil.TEST_CLOSURE);
        Reader transformedReader = filterChain.transform(originalReader);
        assertThat(transformedReader, instanceOf(LineFilter.class));
    }

    @Test
    public void canAddExpandFilterToEndOfChain() throws IOException {
        filterChain.expand(WrapUtil.toMap("prop", 1), escapeBackslashProperty());