Cheolsoo Park created PIG-2931:
----------------------------------
Summary: $ signs in the replacement string make parameter
substitution fail
Key: PIG-2931
URL: https://issues.apache.org/jira/browse/PIG-2931
Project: Pig
Issue Type: Bug
Affects Versions: 0.10.0
Reporter: Cheolsoo Park
Assignee: Cheolsoo Park
Fix For: 0.11
To reproduce the issue, use the following pig script:
{code:title=test.pig}
a = load 'data';
b = filter by $FILTER;
{code}
and run the following command:
{code}
pig -x local -dryrun -f test.pig -p FILTER="(\$0 == 'a')"
{code}
This generates the following script:
{code:title=test.pig.substituted}
a = load 'data';
b = filter by ($FILTER == 'a');
{code}
However this should be:
{code}
a = load 'data';
b = filter by ($0 == 'a');
{code}
This is because Pig calls replaceFirst() with a replacement string that include
a $ sign as follows:
{code}
"$FILTER".replaceFirst("\\$FILTER", "($0 == 'a')"));
{code}
To treat $ signs as literals in the replacement string, we must escape them.
Please see the [Java
doc|http://docs.oracle.com/javase/6/docs/api/java/util/regex/Matcher.html#replaceFirst(java.lang.String)]
for Matcher class for explanation:
{quote}
Note that backslashes (\) and dollar signs ($) in the replacement string may
cause the results to be different than if it were being treated as a literal
replacement string. Dollar signs may be treated as references to captured
subsequences as described above, and backslashes are used to escape literal
characters in the replacement string.
{quote}
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
