From 27806d90a8052fa5ecec0c5980ae2d58adf4a179 Mon Sep 17 00:00:00 2001
From: dajester2013 <dajester2005@gmail.com>
Date: Thu, 23 Jan 2014 05:45:28 -0600
Subject: [PATCH] traversal(_tree) vertex filtering

added params "filterVertices" and "vertexFilterType" to traversal(_tree).  "filterVertices" accepts an array of examples similar to "followEdges", while "vertexFilterType" defines how to filter out vertices that do not match the examples. "vertexFilterType" can be set to "prune", "exclude", or (default) ["prune","exclude"].
---
 js/server/modules/org/arangodb/ahuacatl.js | 56 +++++++++++++++++-----
 1 file changed, 44 insertions(+), 12 deletions(-)

diff --git a/js/server/modules/org/arangodb/ahuacatl.js b/js/server/modules/org/arangodb/ahuacatl.js
index c601ed9526..fff0fb4e45 100644
--- a/js/server/modules/org/arangodb/ahuacatl.js
+++ b/js/server/modules/org/arangodb/ahuacatl.js
@@ -3757,6 +3757,38 @@ function TRAVERSAL_FILTER (config, vertex, edge, path) {
   return MATCHES(edge, config.expandEdgeExamples);
 }
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief vertex filter callback function for traversal
+////////////////////////////////////////////////////////////////////////////////
+
+function TRAVERSAL_VERTEX_FILTER (config, vertex, path) {
+  "use strict";
+  
+  if (!MATCHES(vertex, config.filterVertexExamples)) {
+    return config.vertexFilterType;
+  }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check typeweights of params.followEdges/params.followVertices
+////////////////////////////////////////////////////////////////////////////////
+
+function TRAVERSAL_CHECK_EXAMPLES_TYPEWEIGHTS (examples) {
+  "use strict";
+  
+  if (TYPEWEIGHT(examples) !== TYPEWEIGHT_LIST) {
+    THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
+  }
+  if (examples.length === 0) {
+    THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
+  }
+  examples.forEach(function (example) {
+    if (TYPEWEIGHT(example) !== TYPEWEIGHT_DOCUMENT) {
+      THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
+    }
+  });
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief traverse a graph
 ////////////////////////////////////////////////////////////////////////////////
@@ -3770,20 +3802,14 @@ function TRAVERSAL_FUNC (func, vertexCollection, edgeCollection, startVertex, di
 
   vertexCollection = COLLECTION(vertexCollection);
   edgeCollection   = COLLECTION(edgeCollection);
-
+  
   // check followEdges property
   if (params.followEdges) {
-    if (TYPEWEIGHT(params.followEdges) !== TYPEWEIGHT_LIST) {
-      THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
-    }
-    if (params.followEdges.length === 0) {
-      THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
-    }
-    params.followEdges.forEach(function (example) {
-      if (TYPEWEIGHT(example) !== TYPEWEIGHT_DOCUMENT) {
-        THROW(INTERNAL.errors.ERROR_QUERY_FUNCTION_ARGUMENT_TYPE_MISMATCH, func);
-      }
-    });
+    TRAVERSAL_CHECK_EXAMPLES_TYPEWEIGHTS(params.followEdges);
+  }
+  // check followVertices property
+  if (params.followVertices) {
+    TRAVERSAL_CHECK_EXAMPLES_TYPEWEIGHTS(params.followVertices);
   }
 
   if (typeof params.visitor !== "function") {
@@ -3812,6 +3838,12 @@ function TRAVERSAL_FUNC (func, vertexCollection, edgeCollection, startVertex, di
     config.expandEdgeExamples = params.followEdges;
   }
 
+  if (params.filterVertices) {
+    config.filter = TRAVERSAL_VERTEX_FILTER;
+    config.filterVertexExamples = params.filterVertices;
+  	config.vertexFilterType = params.vertexFilterType || ["prune","exclude"];
+  }
+
   if (params._sort) {
     config.sort = function (l, r) { return l._key < r._key ? -1 : 1; };
   }