Replaced the implementation of SpannableBuilder

SpannableBuilder will now extend SpannableStringBuilder. The major diff-
erence will be that the span order will be reverted upon a call of
`getSpans()`. Another addition will be support for setting multiple
multiple spans by array.

The reverse order implementation is credited Uncodin/bypass

markwon/src/main/java/ru/noties/markwon/SpannableBuilder.java

@@ -5,41 +5,52 @@ import android.support.annotation.Nullable;
 import android.text.SpannableStringBuilder;
 import android.text.Spanned;
 
-import java.util.ArrayDeque;
-import java.util.Deque;
-import java.util.Iterator;
-
 /**
  * This class is used to _revert_ order of applied spans. Original SpannableStringBuilder
  * is using an array to store all the information about spans. So, a span that is added first
  * will be drawn first, which leads to subtle bugs (spans receive wrong `x` values when
  * requested to draw itself)
- * <p>
- * since 2.0.0 implements Appendable and CharSequence
- *
- * @since 1.0.1
  */
-@SuppressWarnings({"WeakerAccess", "unused"})
+public class SpannableBuilder extends SpannableStringBuilder {
-public class SpannableBuilder implements Appendable, CharSequence {
+
+    public SpannableBuilder() {
+        super();
+    }
+
+    public SpannableBuilder(CharSequence text, int start, int end) {
+        super(text, start, end);
+    }
+
+    @Override
+    public <T> T[] getSpans(int queryStart, int queryEnd, Class<T> kind) {
+        T[] ret = super.getSpans(queryStart, queryEnd, kind);
+        reverse(ret);
+        return ret;
+    }
 
     /**
-     * @since 2.0.0
+     * Convenience for allowing {@link Nullable} and {@link NonNull} spans, as well as
+     * {@link NonNull} array of spans. {@link Spanned#SPAN_EXCLUSIVE_EXCLUSIVE} will be applied as
+     * flag.
+     *
+     * @param spans A span object, an array of span objects or null
+     * @param start Start index (inclusive)
+     * @param end   End index (exclusive)
      */
-    public static void setSpans(@NonNull SpannableBuilder builder, @Nullable Object spans, int start, int end) {
+    public void setSpans(@Nullable Object spans, int start, int end) {
         if (spans != null) {
-
             // setting a span for an invalid position can lead to silent fail (no exception,
             // but execution is stopped)
-            if (!isPositionValid(builder.length(), start, end)) {
+            if (!isPositionValid(length(), start, end)) {
                 return;
             }
 
             if (spans.getClass().isArray()) {
                 for (Object o : ((Object[]) spans)) {
-                    builder.setSpan(o, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
+                    setSpan(o, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                 }
             } else {
-                builder.setSpan(spans, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
+                setSpan(spans, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
             }
         }
     }
@@ -50,242 +61,20 @@ public class SpannableBuilder implements Appendable, CharSequence {
                 && end <= length;
     }
 
-
+    private static void reverse(Object[] arr) {
-    private final StringBuilder builder;
+        if (arr == null) {
-
+            return;
-    // actually we might be just using ArrayList
-    private final Deque<Span> spans = new ArrayDeque<>(8);
-
-    public SpannableBuilder() {
-        this("");
-    }
-
-    public SpannableBuilder(@NonNull CharSequence cs) {
-        this.builder = new StringBuilder(cs);
-        copySpans(0, cs);
-    }
-
-    /**
-     * Additional method that takes a String, which is proven to NOT contain any spans
-     *
-     * @param text String to append
-     * @return this instance
-     */
-    @NonNull
-    public SpannableBuilder append(@NonNull String text) {
-        builder.append(text);
-        return this;
-    }
-
-    @NonNull
-    @Override
-    public SpannableBuilder append(char c) {
-        builder.append(c);
-        return this;
-    }
-
-    @NonNull
-    @Override
-    public SpannableBuilder append(@NonNull CharSequence cs) {
-
-        copySpans(length(), cs);
-
-        builder.append(cs);
-
-        return this;
-    }
-
-    /**
-     * @since 2.0.0 to follow Appendable interface
-     */
-    @NonNull
-    @Override
-    public SpannableBuilder append(CharSequence csq, int start, int end) {
-
-        final CharSequence cs = csq.subSequence(start, end);
-        copySpans(length(), cs);
-
-        builder.append(cs);
-
-        return this;
-    }
-
-    @NonNull
-    public SpannableBuilder append(@NonNull CharSequence cs, @NonNull Object span) {
-        final int length = length();
-        append(cs);
-        setSpan(span, length);
-        return this;
-    }
-
-    @NonNull
-    public SpannableBuilder append(@NonNull CharSequence cs, @NonNull Object span, int flags) {
-        final int length = length();
-        append(cs);
-        setSpan(span, length, length(), flags);
-        return this;
-    }
-
-    @NonNull
-    public SpannableBuilder setSpan(@NonNull Object span, int start) {
-        return setSpan(span, start, length());
-    }
-
-    @NonNull
-    public SpannableBuilder setSpan(@NonNull Object span, int start, int end) {
-        return setSpan(span, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
-    }
-
-    @NonNull
-    public SpannableBuilder setSpan(@NonNull Object span, int start, int end, int flags) {
-        spans.push(new Span(span, start, end, flags));
-        return this;
-    }
-
-    @Override
-    public int length() {
-        return builder.length();
-    }
-
-    @Override
-    public char charAt(int index) {
-        return builder.charAt(index);
-    }
-
-    /**
-     * @since 2.0.0 to follow CharSequence interface
-     */
-    @Override
-    public CharSequence subSequence(int start, int end) {
-        return builder.subSequence(start, end);
-    }
-
-    public char lastChar() {
-        return builder.charAt(length() - 1);
-    }
-
-    @NonNull
-    public CharSequence removeFromEnd(int start) {
-
-        // this method is not intended to be used by clients
-        // it's a workaround to support tables
-
-        final int end = length();
-
-        // as we do not expose builder and do no apply spans to it, we are safe to NOT to convert to String
-        final SpannableStringBuilderImpl impl = new SpannableStringBuilderImpl(builder.subSequence(start, end));
-
-        final Iterator<Span> iterator = spans.iterator();
-
-        Span span;
-
-        while (iterator.hasNext() && ((span = iterator.next())) != null) {
-            if (span.start >= start && span.end <= end) {
-                impl.setSpan(span.what, span.start - start, span.end - start, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
-                iterator.remove();
-            }
         }
 
-        builder.replace(start, end, "");
+        int i = 0;
-
+        int j = arr.length - 1;
-        return impl;
+        Object tmp;
-    }
+        while (j > i) {
-
+            tmp = arr[j];
-    @Override
+            arr[j] = arr[i];
-    @NonNull
+            arr[i] = tmp;
-    public String toString() {
+            j--;
-        return builder.toString();
+            i++;
-    }
-
-    @NonNull
-    public CharSequence text() {
-        // @since 2.0.0 redirects this call to `#spannableStringBuilder()`
-        return spannableStringBuilder();
-    }
-
-    /**
-     * Simple method to create a SpannableStringBuilder, which is created anyway. Unlike {@link #text()}
-     * method which returns the same SpannableStringBuilder there is no need to cast the resulting
-     * CharSequence
-     *
-     * @since 2.0.0
-     */
-    @NonNull
-    public SpannableStringBuilder spannableStringBuilder() {
-
-        // okay, in order to not allow external modification and keep our spans order
-        // we should not return our builder
-        //
-        // plus, if this method was called -> all spans would be applied, which potentially
-        // breaks the order that we intend to use
-        // so, we will defensively copy builder
-
-        // as we do not expose builder and do no apply spans to it, we are safe to NOT to convert to String
-
-        final SpannableStringBuilderImpl impl = new SpannableStringBuilderImpl(builder);
-
-        for (Span span : spans) {
-            impl.setSpan(span.what, span.start, span.end, span.flags);
-        }
-
-        return impl;
-    }
-
-    private void copySpans(final int index, @Nullable CharSequence cs) {
-
-        // we must identify already reversed Spanned...
-        // and (!) iterate backwards when adding (to preserve order)
-
-        if (cs instanceof Spanned) {
-
-            final Spanned spanned = (Spanned) cs;
-            final boolean reverse = spanned instanceof SpannedReversed;
-
-            final Object[] spans = spanned.getSpans(0, spanned.length(), Object.class);
-            final int length = spans != null
-                    ? spans.length
-                    : 0;
-
-            if (length > 0) {
-                if (reverse) {
-                    Object o;
-                    for (int i = length - 1; i >= 0; i--) {
-                        o = spans[i];
-                        setSpan(
-                                o,
-                                index + spanned.getSpanStart(o),
-                                index + spanned.getSpanEnd(o),
-                                spanned.getSpanFlags(o)
-                        );
-                    }
-                } else {
-                    Object o;
-                    for (int i = 0; i < length; i++) {
-                        o = spans[i];
-                        setSpan(
-                                o,
-                                index + spanned.getSpanStart(o),
-                                index + spanned.getSpanEnd(o),
-                                spanned.getSpanFlags(o)
-                        );
-                    }
-                }
-            }
         }
     }
-
+}
-    static class Span {
-
-        final Object what;
-        int start;
-        int end;
-        final int flags;
-
-        Span(@NonNull Object what, int start, int end, int flags) {
-            this.what = what;
-            this.start = start;
-            this.end = end;
-            this.flags = flags;
-        }
-    }
-}

markwon/src/main/java/ru/noties/markwon/SpannableStringBuilderImpl.java

@@ -1,13 +0,0 @@
-package ru.noties.markwon;
-
-import android.text.SpannableStringBuilder;
-
-/**
- * @since 1.0.1
- */
-class SpannableStringBuilderImpl extends SpannableStringBuilder implements SpannedReversed {
-
-    SpannableStringBuilderImpl(CharSequence text) {
-        super(text);
-    }
-}

markwon/src/main/java/ru/noties/markwon/SpannedReversed.java

@@ -1,9 +0,0 @@
-package ru.noties.markwon;
-
-import android.text.Spanned;
-
-/**
- * @since 1.0.1
- */
-interface SpannedReversed extends Spanned {
-}

markwon/src/main/java/ru/noties/markwon/renderer/SpannableMarkdownVisitor.java

@@ -415,7 +415,7 @@ public class SpannableMarkdownVisitor extends AbstractVisitor {
 
             pendingTableRow.add(new TableRowSpan.Cell(
                     tableCellAlignment(cell.getAlignment()),
-                    builder.removeFromEnd(length)
+                    removeFromEnd(length)
             ));
 
             tableRowIsHeader = cell.isHeader();
@@ -508,12 +508,13 @@ public class SpannableMarkdownVisitor extends AbstractVisitor {
     }
 
     private void setSpan(int start, @Nullable Object span) {
-        SpannableBuilder.setSpans(builder, span, start, builder.length());
+        builder.setSpans(span, start, builder.length());
     }
 
     private void newLine() {
-        if (builder.length() > 0
+        final int length = builder.length();
-                && '\n' != builder.lastChar()) {
+
+        if (length > 0 && '\n' != builder.charAt(length - 1)) {
             builder.append('\n');
         }
     }
@@ -530,6 +531,21 @@ public class SpannableMarkdownVisitor extends AbstractVisitor {
         return false;
     }
 
+    @NonNull
+    public CharSequence removeFromEnd(int start) {
+        // this method is not intended to be used by clients
+        // it's a workaround to support tables
+
+        final int end = builder.length();
+
+        // as we do not expose builder and do no apply spans to it, we are safe to NOT to convert to String
+        final SpannableBuilder impl = new SpannableBuilder(builder, start, end);
+        builder.delete(start, end);
+
+        return impl;
+    }
+
+
     @TableRowSpan.Alignment
     private static int tableCellAlignment(TableCell.Alignment alignment) {
         final int out;

markwon/src/main/java/ru/noties/markwon/renderer/SpannableRenderer.java

@@ -10,9 +10,9 @@ import ru.noties.markwon.SpannableConfiguration;
 public class SpannableRenderer {
 
     @NonNull
-    public CharSequence render(@NonNull SpannableConfiguration configuration, @NonNull Node node) {
+    public SpannableBuilder render(@NonNull SpannableConfiguration configuration, @NonNull Node node) {
         final SpannableBuilder builder = new SpannableBuilder();
         node.accept(new SpannableMarkdownVisitor(configuration, builder));
-        return builder.text();
+        return builder;
     }
 }

markwon/src/main/java/ru/noties/markwon/renderer/html2/tag/BlockquoteHandler.java

@@ -18,8 +18,7 @@ public class BlockquoteHandler extends TagHandler {
             visitChildren(configuration, builder, tag.getAsBlock());
         }
 
-        SpannableBuilder.setSpans(
+        builder.setSpans(
-                builder,
                 configuration.factory().blockQuote(configuration.theme()),
                 tag.start(),
                 tag.end()

markwon/src/main/java/ru/noties/markwon/renderer/html2/tag/ListHandler.java

@@ -48,7 +48,7 @@ public class ListHandler extends TagHandler {
                             bulletLevel
                     );
                 }
-                SpannableBuilder.setSpans(builder, spans, child.start(), child.end());
+                builder.setSpans(spans, child.start(), child.end());
             }
         }
     }

markwon/src/main/java/ru/noties/markwon/renderer/html2/tag/SimpleTagHandler.java

@@ -14,9 +14,6 @@ public abstract class SimpleTagHandler extends TagHandler {
 
     @Override
     public void handle(@NonNull SpannableConfiguration configuration, @NonNull SpannableBuilder builder, @NonNull HtmlTag tag) {
-        final Object spans = getSpans(configuration, tag);
+        builder.setSpans(getSpans(configuration, tag), tag.start(), tag.end());
-        if (spans != null) {
-            SpannableBuilder.setSpans(builder, spans, tag.start(), tag.end());
-        }
     }
 }

markwon/src/main/java/ru/noties/markwon/renderer/html2/tag/StrikeHandler.java

@@ -18,8 +18,7 @@ public class StrikeHandler extends TagHandler {
             visitChildren(configuration, builder, tag.getAsBlock());
         }
 
-        SpannableBuilder.setSpans(
+        builder.setSpans(
-                builder,
                 configuration.factory().strikethrough(),
                 tag.start(),
                 tag.end()

markwon/src/main/java/ru/noties/markwon/renderer/html2/tag/UnderlineHandler.java

@@ -21,8 +21,7 @@ public class UnderlineHandler extends TagHandler {
             visitChildren(configuration, builder, tag.getAsBlock());
         }
 
-        SpannableBuilder.setSpans(
+        builder.setSpans(
-                builder,
                 configuration.factory().underline(),
                 tag.start(),
                 tag.end()

markwon/src/test/java/ru/noties/markwon/renderer/visitor/SpannableMarkdownVisitorTest.java

@@ -1,7 +1,6 @@
 package ru.noties.markwon.renderer.visitor;
 
 import android.support.annotation.NonNull;
-import android.text.SpannableStringBuilder;
 
 import org.commonmark.node.Node;
 import org.junit.Test;
@@ -50,20 +49,19 @@ public class SpannableMarkdownVisitorTest {
         final Node node = Markwon.createParser().parse(data.input());
         node.accept(visitor);
 
-        final SpannableStringBuilder stringBuilder = builder.spannableStringBuilder();
 
         final TestValidator validator = TestValidator.create(file);
 
         int index = 0;
 
         for (TestNode testNode : data.output()) {
-            index = validator.validate(stringBuilder, index, testNode);
+            index = validator.validate(builder, index, testNode);
         }
 
         // assert that the whole thing is processed
-        assertEquals("`" + stringBuilder + "`", stringBuilder.length(), index);
+        assertEquals("`" + builder + "`", builder.length(), index);
 
-        final Object[] spans = stringBuilder.getSpans(0, stringBuilder.length(), Object.class);
+        final Object[] spans = builder.getSpans(0, builder.length(), Object.class);
         final int length = spans != null
                 ? spans.length
                 : 0;

sample-custom-extension/src/main/java/ru/noties/markwon/sample/extension/IconVisitor.java

@@ -1,6 +1,7 @@
 package ru.noties.markwon.sample.extension;
 
 import android.support.annotation.NonNull;
+import android.text.Spanned;
 import android.text.TextUtils;
 import android.widget.TextView;
 
@@ -51,9 +52,14 @@ public class IconVisitor extends SpannableMarkdownVisitor {
                 final int length = builder.length();
 
                 builder.append(name);
-                builder.setSpan(iconSpanProvider.provide(name, color, size), length);
+                builder.setSpan(
+                        iconSpanProvider.provide(name, color, size),
+                        length,
+                        length,
+                        Spanned.SPAN_EXCLUSIVE_EXCLUSIVE
+                );
                 builder.append(' ');
-                
+
                 return true;
             }
         }

sample-custom-extension/src/main/java/ru/noties/markwon/sample/extension/MainActivity.java

@@ -70,6 +70,6 @@ public class MainActivity extends Activity {
         node.accept(visitor);
 
         // apply
-        textView.setText(builder.text());
+        textView.setText(builder);
     }
 }

sample-latex-math/src/main/java/ru/noties/markwon/sample/jlatexmath/MainActivity.java

@@ -8,7 +8,6 @@ import org.commonmark.node.CustomBlock;
 import org.commonmark.node.Node;
 import org.commonmark.parser.Parser;
 
-import ru.noties.jlatexmath.JLatexMathAndroid;
 import ru.noties.markwon.Markwon;
 import ru.noties.markwon.SpannableBuilder;
 import ru.noties.markwon.SpannableConfiguration;
@@ -83,8 +82,7 @@ public class MainActivity extends Activity {
                 final int length = builder.length();
                 builder.append(latex);
 
-                SpannableBuilder.setSpans(
+                builder.setSpans(
-                        builder,
                         configuration.factory().image(
                                 configuration.theme(),
                                 JLatexMathMedia.makeDestination(latex),
@@ -100,6 +98,6 @@ public class MainActivity extends Activity {
         };
         node.accept(visitor);
 
-        Markwon.setText(textView, builder.text());
+        Markwon.setText(textView, builder);
     }
 }