[markdown] Only match list items that follow a blank line.

Per Dingus.

mode/markdown/markdown.js

@@ -106,6 +106,7 @@ CodeMirror.defineMode("markdown", function(cmCfg, modeCfg) {
 
   function blockNormal(stream, state) {
     
+    var prevLineIsList = (state.list !== false);
     if (state.list !== false && state.indentationDiff >= 0) { // Continued list
       if (state.indentationDiff < 4) { // Only adjust indentation if *not* a code block
         state.indentation -= state.indentationDiff;
@@ -114,7 +115,7 @@ CodeMirror.defineMode("markdown", function(cmCfg, modeCfg) {
     } else if (state.list !== false && state.indentation > 0) {
       state.list = null;
       state.listDepth = Math.floor(state.indentation / 4);
-    } else { // No longer a list
+    } else if (state.list !== false) { // No longer a list
       state.list = false;
       state.listDepth = 0;
     }
@@ -139,7 +140,7 @@ CodeMirror.defineMode("markdown", function(cmCfg, modeCfg) {
       return switchInline(stream, state, footnoteLink);
     } else if (stream.match(hrRE, true)) {
       return hr;
-    } else if (stream.match(ulRE, true) || stream.match(olRE, true)) {
+    } else if ((!prevLineHasContent || prevLineIsList) && (stream.match(ulRE, true) || stream.match(olRE, true))) {
       state.indentation += 4;
       state.list = true;
       state.listDepth++;

mode/markdown/test.js

@@ -130,6 +130,11 @@
   MT("blockquoteNoSpace",
      "[atom >foo]");
 
+  // No blank line before blockquote
+  MT("blockquoteNoBlankLine",
+     "foo",
+     "[atom > bar]");
+
   // Nested blockquote
   MT("blockquoteSpace",
      "[atom > foo]",
@@ -184,6 +189,12 @@
      "[variable-2 1. foo]",
      "[variable-2 2. bar]");
 
+  // Lists require a preceding blank line (per Dingus)
+  MT("listBogus",
+     "foo",
+     "1. bar",
+     "2. hello");
+
   // Formatting in lists (*)
   MT("listAsteriskFormatting",
      "[variable-2 * ][variable-2&em *foo*][variable-2  bar]",