[PIG-4376] NullPointerException accessing a field of an invalid bag from a nested foreach

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.12.0, 0.13.0, 0.14.0
• Fix Version/s: 0.15.0
• Component/s: parser
• Patch Info: Patch Available
• Hadoop Flags: Reviewed
• Assignee: Kevin Springborn
• Reporter: Kevin Springborn
• Created: 09/Jan/15 21:32
• Updated: 07/Jun/15 03:47
• Resolved: 15/Jan/15 19:50

Description

a = load 'x' as (field);
b = foreach a {
  c = LIMIT invalidName 1;
  generate c.foo;
}

Results in the following stack trace:
[main] ERROR org.apache.pig.PigServer - exception during parsing: Error during parsing. null
Failed to parse: null
at org.apache.pig.parser.QueryParserDriver.parse(QueryParserDriver.java:201)
at org.apache.pig.PigServer$Graph.parseQuery(PigServer.java:1735)
at org.apache.pig.PigServer$Graph.access$000(PigServer.java:1443)
at org.apache.pig.PigServer.parseAndBuild(PigServer.java:387)
at org.apache.pig.PigServer.executeBatch(PigServer.java:412)
at org.apache.pig.PigServer.executeBatch(PigServer.java:398)
at org.apache.pig.tools.grunt.GruntParser.executeBatch(GruntParser.java:171)
at org.apache.pig.tools.grunt.GruntParser.processDump(GruntParser.java:741)
at org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:372)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:230)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:205)
at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:81)
at org.apache.pig.Main.run(Main.java:495)
at org.apache.pig.Main.main(Main.java:170)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Caused by: java.lang.NullPointerException
at org.apache.pig.newplan.logical.expression.DereferenceExpression.translateAliasToPos(DereferenceExpression.java:210)
at org.apache.pig.newplan.logical.expression.DereferenceExpression.getFieldSchema(DereferenceExpression.java:149)
at org.apache.pig.newplan.logical.optimizer.FieldSchemaResetter.execute(SchemaResetter.java:264)
at org.apache.pig.newplan.logical.expression.AllSameExpressionVisitor.visit(AllSameExpressionVisitor.java:148)
at org.apache.pig.newplan.logical.expression.DereferenceExpression.accept(DereferenceExpression.java:84)
at org.apache.pig.newplan.ReverseDependencyOrderWalker.walk(ReverseDependencyOrderWalker.java:70)
at org.apache.pig.newplan.PlanVisitor.visit(PlanVisitor.java:52)
at org.apache.pig.newplan.logical.optimizer.SchemaResetter.visitAll(SchemaResetter.java:67)
at org.apache.pig.newplan.logical.optimizer.SchemaResetter.visit(SchemaResetter.java:122)
at org.apache.pig.newplan.logical.relational.LOGenerate.accept(LOGenerate.java:245)
at org.apache.pig.newplan.DependencyOrderWalker.walk(DependencyOrderWalker.java:75)
at org.apache.pig.newplan.logical.optimizer.SchemaResetter.visit(SchemaResetter.java:114)
at org.apache.pig.parser.LogicalPlanBuilder.buildForeachOp(LogicalPlanBuilder.java:1055)
at org.apache.pig.parser.LogicalPlanGenerator.foreach_clause(LogicalPlanGenerator.java:15896)
at org.apache.pig.parser.LogicalPlanGenerator.op_clause(LogicalPlanGenerator.java:1933)
at org.apache.pig.parser.LogicalPlanGenerator.general_statement(LogicalPlanGenerator.java:1102)
at org.apache.pig.parser.LogicalPlanGenerator.statement(LogicalPlanGenerator.java:560)
at org.apache.pig.parser.LogicalPlanGenerator.query(LogicalPlanGenerator.java:421)
at org.apache.pig.parser.QueryParserDriver.parse(QueryParserDriver.java:191)