Fix: handle the edge case of empty text buffer

Author: hypest

aztec/src/main/kotlin/org/wordpress/aztec/handlers/HeadingHandler.kt

@@ -44,7 +44,13 @@ class HeadingHandler : BlockHandler<AztecHeadingSpan>(AztecHeadingSpan::class.ja
     }
 
     override fun handleEndOfBufferMarker() {
-        // adjust the block end to only include the chars before the end-of-text marker. A newline will be there.
+        if (block.start == markerIndex) {
+            // ok, this list item has the marker as its first char so, nothing more to do here.
+            return
+        }
+
+        // the heading has bled over to the marker so, let's adjust its range to just before the marker.
+        //  There's a newline there hopefully :)
         block.end = markerIndex
     }
 

aztec/src/main/kotlin/org/wordpress/aztec/watchers/ParagraphCollapseRemover.kt

@@ -21,7 +21,8 @@ class ParagraphCollapseRemover private constructor(aztecText: AztecText) : TextW
 
         val charsOld = s.subSequence(start, start + count) as Spanned
 
-        val paragraphs = SpanWrapper.getSpans(s as Spannable, start, start + count, ParagraphFlagged::class.java)
+        val paragraphs = SpanWrapper.getSpans(s as Spannable,
+                start, start + count, ParagraphFlagged::class.java)
         if (paragraphs.isEmpty() && start + count >= s.length) {
             // no paragraphs in the text to be removed and no other text beyond the change so, nothing to do here. Bail.
             return
@@ -44,6 +45,7 @@ class ParagraphCollapseRemover private constructor(aztecText: AztecText) : TextW
             }
 
             if (start + lastNewlineIndex + 2 > s.length) {
+
                 continue
             }