From 1ed60150aa8d007acd895d0ab7274ba9eb8b0f2a Mon Sep 17 00:00:00 2001
From: Tomas Gavenciak <gavento@ucw.cz>
Date: Wed, 22 Sep 2010 23:26:32 +0200
Subject: [PATCH] Added ConfigTree.remove, adapted parse and parse_file

parse(_file) returns list of operations.
remove removes these from the config

Includes a testcase
---
 t/moe/config.py      | 16 +++++++++++++---
 t/moe/config_test.py | 17 +++++++++++++++++
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/t/moe/config.py b/t/moe/config.py
index b2f788e..04e363f 100644
--- a/t/moe/config.py
+++ b/t/moe/config.py
@@ -101,11 +101,21 @@ class ConfigTree(object):
     for key in keys:
       self.lookup(key, create=True).fix()
 
+  def remove(self, parsed):
+    """Given a list [(varname, `Operation`)] as returned by `parse` or `parse_file`, 
+    removes the operations from the respective variables config tree.
+    Variables/operations not present int the tree raise ValueError.
+    """
+    for vname, o in parsed:
+      v = self.lookup(vname, create = True)
+      v.remove_operation(o)
+
   def parse(self, s, source=None, level=0):
-    """Parse `s` (stream/string) into the tree, see `moe.confparser.ConfigParser` for details."""
+    """Parse `s` (stream/string) into the tree, see `moe.confparser.ConfigParser` for details.
+    Returns list of parset operations: [(varname, `Operation`)]"""
     import moe.config_parser
     p = moe.config_parser.ConfigParser(s, self, source=source, level=level)
-    p.parse()
+    return p.parse()
 
   def parse_file(self, filename, desc=None, level=0):
     """Parse an utf-8 file into the tree, see `moe.confparser.ConfigParser` for details. 
@@ -113,7 +123,7 @@ class ConfigTree(object):
     with open(filename, 'rt') as f:
       if desc: 
 	filename += " <" + desc + ">" 
-      self.parse(f, source=filename, level=level)
+      return self.parse(f, source=filename, level=level)
 
 
 class ConfigElem(object):
diff --git a/t/moe/config_test.py b/t/moe/config_test.py
index c19645a..2a0325b 100644
--- a/t/moe/config_test.py
+++ b/t/moe/config_test.py
@@ -82,6 +82,23 @@ class TestParser(TestConfig):
     s.assertRaises(ConfigSyntaxError, s.parse, "if ('{a}'=='{b}' ornot ''!='') {}")
     s.assertRaises(ConfigSyntaxError, s.parse, "if 'a'<>'b' {}")
 
+  def test_parse_remove(s):
+    s.parse('a="000"')
+    d1 = s.parse("a='A'; b='B'; c='C'", level=10)
+    d2 = s.parse('c="{a}{a}"; b="XX" ', level=20)
+    d3 = s.parse('b+=c ', level=30)
+    assert s.val('b') == "XXAA"
+    s.t.remove(d2)
+    assert s.val('b') == "BC"
+    s.assertRaises(ValueError, s.t.remove, [('d', d1[1][0])])
+    s.assertRaises(ValueError, s.t.remove, [('b', d1[1][0])])
+    # partially remove d1
+    s.t.remove([('c', d1[2][1])])
+    # try to remove rest - 'a' and 'b' should get removed
+    s.assertRaises(ValueError, s.t.remove, d1)
+    assert s.val('a') == "000"
+    s.t.remove(d3)
+
 
 class TestConfigEval(TestConfig):
 
-- 
2.39.2