From 3d46a76f6b1f4339f84dee0c099c5f7675f3b6ca Mon Sep 17 00:00:00 2001
From: Arian Treffer <derari@web.de>
Date: Thu, 18 Feb 2016 16:03:36 +0100
Subject: [PATCH 1/2] Failing test to demonstrate bug

---
 .../java/org/commonmark/test/ParserTest.java  | 32 +++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/commonmark/src/test/java/org/commonmark/test/ParserTest.java b/commonmark/src/test/java/org/commonmark/test/ParserTest.java
index d6a46d58d..6c6915919 100644
--- a/commonmark/src/test/java/org/commonmark/test/ParserTest.java
+++ b/commonmark/src/test/java/org/commonmark/test/ParserTest.java
@@ -5,7 +5,6 @@
 import org.commonmark.parser.Parser;
 import org.commonmark.parser.block.*;
 import org.commonmark.spec.SpecReader;
-import org.hamcrest.CoreMatchers;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -13,9 +12,9 @@
 import java.io.InputStreamReader;
 
 import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.CoreMatchers.notNullValue;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
-import static org.junit.Assert.assertTrue;
 
 public class ParserTest {
 
@@ -47,6 +46,35 @@ public void customBlockParserFactory() {
         assertEquals("hey", ((Text) document.getFirstChild().getFirstChild()).getLiteral());
         assertThat(document.getLastChild(), instanceOf(DashBlock.class));
     }
+    
+    @Test
+    public void indentation() {
+        String given = " - 1 space\n   - 3 spaces\n     - 5 spaces\n\t - tab + space";
+        Parser parser = Parser.builder().build();
+        Node document = parser.parse(given);
+        
+        assertThat(document.getFirstChild(), instanceOf(BulletList.class));
+        
+        Node list = document.getFirstChild(); // first level list
+        assertEquals("expect one child", list.getFirstChild(), list.getLastChild());
+        assertEquals("1 space", firstText(list.getFirstChild()));
+        
+        list = list.getFirstChild().getLastChild(); // second level list
+        assertEquals("expect one child", list.getFirstChild(), list.getLastChild());
+        assertEquals("3 spaces", firstText(list.getFirstChild()));
+        
+        list = list.getFirstChild().getLastChild(); // third level list
+        assertEquals("5 spaces", firstText(list.getFirstChild()));
+        assertEquals("tab + space", firstText(list.getFirstChild().getNext()));
+    }
+    
+    private String firstText(Node n) {
+        while (!(n instanceof Text)) {
+            assertThat(n, notNullValue());
+            n = n.getFirstChild();
+        }
+        return ((Text) n).getLiteral();
+    }
 
     private static class DashBlock extends CustomBlock {
     }

From fdcc279b0f278d836e096ea6fb48e4e6ff898f65 Mon Sep 17 00:00:00 2001
From: Arian Treffer <derari@web.de>
Date: Thu, 18 Feb 2016 16:29:57 +0100
Subject: [PATCH 2/2] Bug fixed for tabbed columns

---
 .../main/java/org/commonmark/internal/DocumentParser.java    | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/commonmark/src/main/java/org/commonmark/internal/DocumentParser.java b/commonmark/src/main/java/org/commonmark/internal/DocumentParser.java
index 27dbde7cf..29a6c5de8 100644
--- a/commonmark/src/main/java/org/commonmark/internal/DocumentParser.java
+++ b/commonmark/src/main/java/org/commonmark/internal/DocumentParser.java
@@ -297,6 +297,11 @@ private void setNewColumn(int newColumn) {
         while (column < newColumn && index != line.length()) {
             advance();
         }
+        if (column > newColumn) {
+            // Last character was a tab and we overshot our target
+            index--;
+            column = newColumn;
+        }
     }
 
     private void advance() {