From 139011e1aec1452b933ff78810d03affdbaeb8b8 Mon Sep 17 00:00:00 2001
From: Paul Beckingham <paul@beckingham.net>
Date: Tue, 24 Apr 2012 00:53:04 -0400
Subject: [PATCH] Performance

- Introduced a new filter optimization that recognizes filters with no 'OR', or
  'XOR' operators, includes IDs, but does not include UUIDs.  This combination
  means completed.data is not referenced.
---
 ChangeLog                |  3 +++
 src/commands/Command.cpp | 32 ++++++++++++++++++++++++++++++--
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 7aeb3d21f..dcfc3aaa3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,9 @@ Features
  + Added the new 'indented' format for the 'project' attribute.
  + The 'projects' report now uses 'project.indented' format.
  + The 'summary' report now uses 'project.indented' format.
+ + Introduced a new filter optimization that recognizes filters with no 'OR', or
+   'XOR' operators, includes IDs, but does not include UUIDs.  This combination
+   means completed.data is not referenced.
 
 Bugs
  + Fixed bug #964, where the 'projects' command showed the wrong priority labels
diff --git a/src/commands/Command.cpp b/src/commands/Command.cpp
index 98bb7b049..cf50a7648 100644
--- a/src/commands/Command.cpp
+++ b/src/commands/Command.cpp
@@ -338,8 +338,6 @@ void Command::filter (std::vector <Task>& output)
         if (e.evalFilter (*task))
           output.push_back (*task);
     }
-    else
-      context.debug ("Command::filter skipping completed.data");
   }
   else
   {
@@ -372,7 +370,37 @@ bool Command::filter_shortcut (const A3& filter)
       filter[0]._raw                  == "status"          &&
       filter[1]._raw.find ("pending") != std::string::npos &&
       filter[2]._raw                  == "=")
+  {
+    context.debug ("Command::filter skipping completed.data (status:pending only)");
     return true;
+  }
+
+  // Shortcut: If the filter contains no 'or' or 'xor' operators, IDs and no UUIDs.
+  int countId   = 0;
+  int countUUID = 0;
+  int countOr   = 0;
+  int countXor  = 0;
+  std::vector <Arg>::const_iterator i;
+  for (i = filter.begin (); i != filter.end (); ++i)
+  {
+    if (i->_category == Arg::cat_op)
+    {
+      if (i->_raw == "or")  ++countOr;
+      if (i->_raw == "xor") ++countXor;
+
+    }
+    else if (i->_category == Arg::cat_id)   ++countId;
+    else if (i->_category == Arg::cat_uuid) ++countUUID;
+  }
+
+  if (countOr   == 0 &&
+      countXor  == 0 &&
+      countUUID == 0 &&
+      countId    > 0)
+  {
+    context.debug ("Command::filter skipping completed.data (IDs, no OR, no XOR, no UUID)");
+    return true;
+  }
 
   return false;
 }