JRuby

Dir#pos= dies if negative value provided

Details

  • Type: Bug Bug
  • Status: Closed Closed
  • Priority: Minor Minor
  • Resolution: Fixed
  • Affects Version/s: JRuby 1.6
  • Fix Version/s: JRuby 1.6.1
  • Component/s: Core Classes/Modules, Intro
  • Labels:
    None
  • Environment:
    jruby 1.6.0 (ruby 1.8.7 patchlevel 330) (2011-03-15 f3b6154) (OpenJDK Client VM 1.6.0_20) [linux-i386-java]
  • Testcase included:
    yes
  • Number of attachments :
    1

Description

In MRI the Dir#pos= method accepts a negative value. It's effectively a no-op if a read has not occurred yet, or returns nil if at least one read has already occurred, which I assume moves the pointer to the end of the stream. The behavior is curious, and I suspect it's driven by the rules of the underlying seekdir() function, though I haven't thoroughly scoured the source, and the man page for seekdir() made no mention of negative values.

JRuby fails with an Java::JavaLang::ArrayIndexOutOfBoundsException.

I've attached the test suite I'm using for berger_spec.

Activity

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Hiro Asari added a comment -

I haven't looked at the source, but from the sound of it, it should be pretty straightforward to fix.

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Hiro Asari added a comment - I haven't looked at the source, but from the sound of it, it should be pretty straightforward to fix.
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Charles Oliver Nutter added a comment - - edited

This is weird...I can't tell that it does anything at all:

~/projects/jruby ➔ ruby -e "dir = Dir.new(File.dirname(__FILE__)); dir.pos = -1; p dir.read; dir.pos = -1; p dir.read; dir.pos = -1; p dir.read"
"."
".."
".classpath"

~/projects/jruby ➔ ruby -e "dir = Dir.new(File.dirname(__FILE__)); p dir.read; p dir.read; p dir.read"
"."
".."
".classpath"
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Charles Oliver Nutter added a comment - - edited This is weird...I can't tell that it does anything at all: ~/projects/jruby ➔ ruby -e "dir = Dir.new(File.dirname(__FILE__)); dir.pos = -1; p dir.read; dir.pos = -1; p dir.read; dir.pos = -1; p dir.read" "." ".." ".classpath" ~/projects/jruby ➔ ruby -e "dir = Dir.new(File.dirname(__FILE__)); p dir.read; p dir.read; p dir.read" "." ".." ".classpath"
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Charles Oliver Nutter added a comment -

At least one article says a negative value passed to seekdir does nothing at all.

http://publib.boulder.ibm.com/infocenter/zos/v1r10/index.jsp?topic=/com.ibm.zos.r10.bpxbd00/rsekdr.htm

I'll make us match.

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Charles Oliver Nutter added a comment - At least one article says a negative value passed to seekdir does nothing at all. http://publib.boulder.ibm.com/infocenter/zos/v1r10/index.jsp?topic=/com.ibm.zos.r10.bpxbd00/rsekdr.htm I'll make us match.
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Charles Oliver Nutter added a comment -

commit 88e0b0075f417cfad43ef7baa9e9fe74f2ecc7ac
Author: Charles Oliver Nutter <headius@headius.com>
Date: Thu Mar 31 17:53:01 2011 -0500

Fix JRUBY-5640: Dir#pos= dies if negative value provided

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Charles Oliver Nutter added a comment - commit 88e0b0075f417cfad43ef7baa9e9fe74f2ecc7ac Author: Charles Oliver Nutter <headius@headius.com> Date: Thu Mar 31 17:53:01 2011 -0500 Fix JRUBY-5640 : Dir#pos= dies if negative value provided
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Daniel Berger added a comment -

That's what I figured. Thanks for the link. I need to double check MRI's behavior on this.

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Daniel Berger added a comment - That's what I figured. Thanks for the link. I need to double check MRI's behavior on this.

People

  • Assignee:
    Charles Oliver Nutter
    Reporter:
    Daniel Berger
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Dates

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    Updated:
    Resolved: