[tahoe-lafs-trac-stream] [Tahoe-LAFS] #2272: Make `python ./setup.py trial` output friendlier if there has not been a build.

[Tahoe-LAFS]

#2272: Make `python ./setup.py trial` output friendlier if there has not been a
build.
----------------------+---------------------------
 Reporter:  nejucomo  |          Owner:  daira
     Type:  defect    |         Status:  new
 Priority:  normal    |      Milestone:  undecided
Component:  unknown   |        Version:  1.10.0
 Keywords:            |  Launchpad Bug:
----------------------+---------------------------
 I just did this:

 {{{
 $ python ./setup.py trial
 running update_version
 git-version: wrote '1.10.0-89-gb7f3585' into 'src/allmydata/_version.py'
 running trial
 /home/n/virtualenvs/default/bin/python: can't open file 'bin/tahoe':
 [Errno 2] No such file or directory
 }}}

 Then I asked people in Nuts & Bolts about this and learned some details.
 It would be potentially helpful for other if the output instead looked
 like this:

 {{{
 $ python ./setup.py trial
 running update_version
 git-version: wrote '1.10.0-89-gb7f3585' into 'src/allmydata/_version.py'
 running trial
 Error: 'bin/tahoe' does not exist. The trial command requires tahoe to be
 built.

 You can explicitly build tahoe by running:

 $ python ./setup.py build

 You can build and run trial in a single command by running:

 $ python ./setup.py test
 }}}

 **Note:** The usage text already clearifies this:

 {{{
 $ python ./setup.py --help-commands | grep -E 'test|trial'
   test              run unit tests after in-place build
   trial             run trial (use 'bin/tahoe debug trial' for the full
 set of trial options)
 }}}

 **Note:** Prior to running `trial`, I searched in `./docs` for something
 like `testing.rst`.  Zooko tells me this lives on the wiki, but it seems
 like it should live in `./docs` because it's revision specific and useful
 even when I'm offline.

--
Ticket URL: <https://tahoe-lafs.org/trac/tahoe-lafs/ticket/2272>
Tahoe-LAFS <https://Tahoe-LAFS.org>
secure decentralized storage