RFR 8179856: jshell tool: not suitable for pipeline use

[Robert Field]

Thanks Jan!

During CSR review, John pointed out problems with the --help text 
(suggesting an alternative) and one case where fluff (informative 
non-essential information) is printed for a load file (including "-") 
and the fluff is wrong (for load files).

The new webrev is here:

     http://cr.openjdk.java.net/~rfield/8179856v5.webrev/

But all that changed is the --help output, instead of my poorly crafted 
words, now ends with:

     A file argument may be a file name, or one of the predefined file 
names: DEFAULT,
     PRINTING, or JAVASE.
     A load file may also be "-" to indicate standard input, without 
interactive I/O.

And on unexpected termination, the output has been broken into two parts:

     jshell.msg.terminated = State engine terminated.
     jshell.msg.terminated.restore = Restore definitions with: /reload 
-restore

The latter is now printed as fluff (and thus not showing up for load 
files or quiet feedback modes):

           shutdownSubscription = state.onShutdown((JShell deadState) -> {
               if (deadState == state) {
                   hardmsg("jshell.msg.terminated");
+                 fluffmsg("jshell.msg.terminated.restore");
                   live = false;
               }
           });

And, of course, the test files are in their new post-consolidation 
locations.

Thanks,
Robert

On 09/15/17 02:49, Jan Lahoda wrote:
> Seems OK to me.
>
> Jan
>
> On 13.9.2017 04:17, Robert Field wrote:
>> Please review updated webrev (now uses file "-" rather than option
>> "--pipe") --
>>
>> Bugs:
>>
>>      8179856: jshell tool: not suitable for pipeline use
>> https://bugs.openjdk.java.net/browse/JDK-8179856
>>
>>      8186708: jshell tool: bad load file garbles message and does not 
>> abort
>> https://bugs.openjdk.java.net/browse/JDK-8186708
>>
>> Webrev:
>>
>> http://cr.openjdk.java.net/~rfield/8179856v2.webrev/
>>
>> Thanks,
>> Robert
>>
>>
>> On 09/12/17 12:53, Robert Field wrote:
>>> I like it!
>>>
>>> Both because it is clean and a standard.
>>> I agree that considering stdin exhausted (so exiting after) makes 
>>> sense.
>>>
>>> It will mean somewhat of a rewrite, but that’s fine.
>>>
>>> I’ll redo and send out.
>>>
>>> -Robert
>>>
>>>> On Sep 12, 2017, at 8:47 AM, Jan Lahoda <jan.lahoda at oracle.com> wrote:
>>>>
>>>> What would happen if we processed "-" (stdin) as a file? One
>>>> difference I see is that after processing the files, the interactive
>>>> shell is started unless there is an explicit /exit in the files. But
>>>> given we have already processed the stdin, it would seem OK to me to
>>>> not start the interactive part (there's an EOF at the end of the
>>>> stdin, I assume, which for stdin could be seen as an explicit /exit).
>>>>
>>>> I also tried bash:
>>>> $ echo 'echo X' | bash -
>>>> X
>>>>
>>>> Jan
>>>>
>>>> On 11.9.2017 18:35, Robert Field wrote:
>>>>> On 09/11/17 02:30, Jan Lahoda wrote:
>>>>>> Hi Robert,
>>>>>>
>>>>>> Overall seems OK to me. One question: why use "--pipe" instead of
>>>>>> simply "-" (which is AFAIK common option for "read stdin")?
>>>>>  From Linux "cat" -----
>>>>>
>>>>> SYNOPSIS
>>>>>         cat [OPTION]... [FILE]...
>>>>>
>>>>> DESCRIPTION
>>>>>         ...
>>>>>
>>>>>         With no FILE, or when FILE is -, read standard input.
>>>>>
>>>>> EXAMPLES
>>>>>         cat f - g
>>>>>                Output f's contents, then standard input, then g's
>>>>> contents.
>>>>>
>>>>>         cat    Copy standard input to standard output.
>>>>>
>>>>> ------------
>>>>>
>>>>> The jshell tool always reads from standard in (unless somehow 
>>>>> aborted).
>>>>> This "--pipe" argument is an option, whereas "-" in the *nix world 
>>>>> is a
>>>>> file.
>>>>>
>>>>> The option does not change what is read, but how it is processed.
>>>>>
>>>>> But maybe that is too pedantic, and it still the natural choice.
>>>>>
>>>>> Thoughts?
>>>>>
>>>>> -Robert
>>>>>
>>>>>
>>>>>> Jan
>>>>>>
>>>>>> On 24.8.2017 06:35, Robert Field wrote:
>>>>>>> Please review --
>>>>>>>
>>>>>>> Bugs:
>>>>>>>
>>>>>>>      8179856: jshell tool: not suitable for pipeline use
>>>>>>>      https://bugs.openjdk.java.net/browse/JDK-8179856
>>>>>>>
>>>>>>>      8186708: jshell tool: bad load file garbles message and 
>>>>>>> does not
>>>>>>> abort
>>>>>>>      https://bugs.openjdk.java.net/browse/JDK-8186708
>>>>>>>
>>>>>>> Webrev:
>>>>>>>
>>>>>>> http://cr.openjdk.java.net/~rfield/8179856v1.webrev/
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Robert
>>>>>>>
>>