[PATCH 1 of 5 V2] color: extract method for determining a valid effect

[Sean Farley]

# HG changeset patch
# User Sean Farley <sean.michael.farley at gmail.com>
# Date 1396902796 18000
#      Mon Apr 07 15:33:16 2014 -0500
# Node ID 20427149f64472231b279bc17ade980cae402d8c
# Parent  12f161f08d744f0e4b6eef9c905670afb5c24dd4
color: extract method for determining a valid effect

diff --git a/hgext/color.py b/hgext/color.py
--- a/hgext/color.py
+++ b/hgext/color.py
@@ -309,10 +309,19 @@ def render_effects(text, effects):
 
 def extstyles():
     for name, ext in extensions.extensions():
         _styles.update(getattr(ext, 'colortable', {}))
 
+def valideffect(effect):
+    'Determine if the effect is valid or not.'
+    good = False
+    if not _terminfo_params and effect in _effects:
+        good = True
+    elif effect in _terminfo_params or effect[:-11] in _terminfo_params:
+        good = True
+    return good
+
 def configstyles(ui):
     for status, cfgeffects in ui.configitems('color'):
         if '.' not in status or status.startswith('color.'):
             continue
         cfgeffects = ui.configlist('color', status)