Auto merge of ycm-core#292 - oblitum:improved-semantic-trigger-match,…

… r=Valloric

Improves semantic trigger match.

Improves semantic trigger match.

Match triggers until user's caret column solely. Trying to match
triggers with characters after user's caret column doesn't seem
to have any utility.

---

This is the first in a series of pull-requests that will transparently enable
ycm-core#1300 for any completer that cares for. After this minimal foundation is
stablished, an initial Swift completer will be available, supporting diagnostics,
fix-it's, semantic completion and argument hints. Changes will also be
proposed to enable hints for C and C++.

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ycmd/completers/completer_utils.py

@@ -97,6 +97,9 @@ def _MatchesSemanticTrigger( line_value, start_column, trigger_list ):
   if not line_length or start_column > line_length:
     return False
 
+  # ignore characters after user's caret column
+  line_value = line_value[ :start_column ]
+
   match = False
   for trigger in trigger_list:
     match = ( _StringTriggerMatches( trigger, line_value, start_column )