Raise Errno::ENOTDIR if the parent of an opened file is not a directory

[philr]

MRI 2.4.2 raises Errno::ENOTDIR when attempting to open a path where the parent entry is not a directory. For example, supposing /tmp/file1 is a regular file:

> File.open('/tmp/file1/file2')
Errno::ENOTDIR: Not a directory @ rb_sysopen - /tmp/file1/file2
        from (irb):1:in `initialize'
        from (irb):1:in `open'
        from (irb):1

However, JRuby 9.1.13.0 (on platforms other than Windows) raises Java::JavaLang::RuntimeException instead:

> File.open('/tmp/file1/file2')
Java::JavaLang::RuntimeException: Unhandled IOException: java.io.IOException: unhandled errno: Not a directory
        from org.jruby.util.io.PosixShim.open(PosixShim.java:426)
        from org.jruby.RubyIO.cloexecOpen(RubyIO.java:1266)
        from org.jruby.RubyIO.sysopenFunc(RubyIO.java:1252)
        from org.jruby.RubyIO.sysopenInternal(RubyIO.java:1244)
        from org.jruby.RubyIO.sysopen(RubyIO.java:1229)
        from org.jruby.RubyFile.fileOpenGeneric(RubyFile.java:1373)
        from org.jruby.RubyFile.openFile(RubyFile.java:1350)
        from org.jruby.RubyFile.initialize(RubyFile.java:366)
        from org.jruby.RubyFile$INVOKER$i$0$3$initialize.call(RubyFile$INVOKER$i$0$3$initialize.gen)
        from org.jruby.runtime.callsite.CachingCallSite.callBlock(CachingCallSite.java:77)
        from org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:83)
        from org.jruby.RubyClass.newInstance(RubyClass.java:1022)
        from org.jruby.RubyIO.open(RubyIO.java:1154)
        from org.jruby.RubyIO$INVOKER$s$0$0$open.call(RubyIO$INVOKER$s$0$0$open.gen)

This pull request changes RegularFileResource.openChannel() and PosixShim.open() so that they handle the ENOTDIR case, making File.open raise the correct exception.

The change only applies to platforms other than Windows. On Windows, both JRuby and MRI raise Errno::ENOENT for such paths.

[kares]

well done, thanks Phil

[kares]

seems that some tests from the test:jruby suite started failing, afterwards e.g. https://travis-ci.org/jruby/jruby/jobs/288206627#L1452-L1461 ... maybe just need adjusting - could you check them with MRI 2.3/2.4?

[philr]

@kares Those tests were already failing on master prior to this change (see https://travis-ci.org/jruby/jruby/jobs/287161724#L1414-L1424).

It looks like either 404fdc9 or 471b9c9 caused the breakage.

[kares]

that seems right - 6 failures of the same but your added test-case passed, sorry for the confusion

[kares]

picked on master as 870011e

keeping open as likely this makes sense to be backported for 9.1 ...

[enebo]

This appears to be only for 2.4 and higher so no backporting.

[philr]

@enebo The Errno::ENOTDIR exception is raised by earlier MRI versions too. I've just checked 1.9.3, 2.0.0, 2.1.10, 2.2.8 and 2.3.5 and they all behave identically to 2.4.2.

[enebo]

@philr omg I did not read that file1 had to exist. You are correct and we should backport as well. I will re-open.

[kares]

double checked on 2.3.3 :

2.3.3 :001 > File.open('/tmp/file1/file2')
Errno::ENOENT: No such file or directory @ rb_sysopen - /tmp/file1/file2
	from (irb):1:in `initialize'
	from (irb):1:in `open'
	from (irb):1
	from /opt/local/rvm/rubies/ruby-2.3.3/bin/irb:11:in `<main>'
2.3.3 :002 > exit
kares@sputnik:~/workspace/oss/jruby-rack-worker$ touch /tmp/file1
kares@sputnik:~/workspace/oss/jruby-rack-worker$ irb
2.3.3 :001 > File.open('/tmp/file1/file2')
Errno::ENOTDIR: Not a directory @ rb_sysopen - /tmp/file1/file2
	from (irb):1:in `initialize'
	from (irb):1:in `open'
	from (irb):1
	from /opt/local/rvm/rubies/ruby-2.3.3/bin/irb:11:in `<main>'

[kares]

now on jruby-.9.1 as well ... e7086e5
Thanks, Phil.