Support custom intro node, fixes #318

lib/parse/navigation.js

@@ -12,6 +12,27 @@ function flattenChapters(chapters) {
     }, []);
 }
 
+function defaultChapters(flatChapters) {
+    // Special README nav
+    var README_NAV = {
+        path: 'README.md',
+        title: 'Introduction',
+        level: '0',
+    };
+
+    // First chapter
+    var first = _.first(flatChapters);
+
+    // Check for intro node
+    if(first && first.path === 'README.md') {
+        // If present, return unmodified
+        return flatChapters;
+    }
+
+    // Otherwise add in default node
+    return [README_NAV].concat(flatChapters);
+}
+
 // Returns from a summary a map of
 /*
     {
@@ -26,15 +47,9 @@ function navigation(summary, files) {
     // Support single files as well as list
     files = _.isArray(files) ? files : (_.isString(files) ? [files] : null);
 
-    // Special README nav
-    var README_NAV = {
-        path: 'README.md',
-        title: 'Introduction',
-        level: '0',
-    };
-
     // List of all navNodes
-    var navNodes = [README_NAV].concat(flattenChapters(summary.chapters));
+    // Flatten chapters, then add in default README node if ndeeded etc ...
+    var navNodes = defaultChapters(flattenChapters(summary.chapters));
     var prevNodes = [null].concat(navNodes.slice(0, -1));
     var nextNodes = navNodes.slice(1).concat([null]);