Re: check-functional skipUnless failure

[Thomas Huth <thuth@redhat.com>]

On 10/09/2024 08.41, Philippe Mathieu-Daudé wrote:
> On 10/9/24 05:58, Richard Henderson wrote:
>> [rth@cfarm120 bld]$ make check-functional
>> [1/2] Generating tests/functional/func-precache-m68k-m68k_nextcube with a 
>> custom command (wrapped by meson to set env)
>> FAILED: tests/functional/m68k-m68k_nextcube.tstamp
>> env 
>> QEMU_TEST_PRECACHE=/home/rth/qemu/bld/tests/functional/m68k-m68k_nextcube.tstamp PYTHONPATH=/home/rth/qemu/src/python:/home/rth/qemu/src/tests/functional /home/rth/qemu/bld/pyvenv/bin/python3 /home/rth/qemu/src/tests/functional/test_m68k_nextcube.py
>> Traceback (most recent call last):
>>    File "/home/rth/qemu/src/tests/functional/test_m68k_nextcube.py", line 
>> 25, in <module>
>>      class NextCubeMachine(QemuSystemTest):
>>    File "/home/rth/qemu/src/tests/functional/test_m68k_nextcube.py", line 
>> 60, in NextCubeMachine
>>      @skipUnless(tesseract_available(4), 'tesseract OCR tool not available')
>>    File "/home/rth/qemu/src/tests/functional/qemu_test/tesseract.py", line 
>> 16, in tesseract_available
>>      (stdout, stderr, ret) = run_cmd([ 'tesseract', '--version'])
>>    File "/home/rth/qemu/src/tests/functional/qemu_test/cmd.py", line 69, 
>> in run_cmd
>>      subp = subprocess.Popen(args,
>>    File "/usr/lib64/python3.9/subprocess.py", line 951, in __init__
>>      self._execute_child(args, executable, preexec_fn, close_fds,
>>    File "/usr/lib64/python3.9/subprocess.py", line 1837, in _execute_child
>>      raise child_exception_type(errno_num, err_msg, err_filename)
>> FileNotFoundError: [Errno 2] No such file or directory: 'tesseract'
>>
>>
>> On this host, tesseract is not available.
>> But skipUnless is not skipping, but erroring out.

Ouch, it's a stupid mistake that I made while converting the test: has_cmd 
returns a list, not a boolean value. This should fix the bug:

diff --git a/tests/functional/qemu_test/tesseract.py 
b/tests/functional/qemu_test/tesseract.py
--- a/tests/functional/qemu_test/tesseract.py
+++ b/tests/functional/qemu_test/tesseract.py
@@ -11,7 +11,8 @@
  from . import has_cmd, run_cmd

  def tesseract_available(expected_version):
-    if not has_cmd('tesseract'):
+    (has_tesseract, errmsg) = has_cmd('tesseract')
+    if not has_tesseract:
          return False
      (stdout, stderr, ret) = run_cmd([ 'tesseract', '--version'])
      if ret:

I'll send it out as a proper patch ASAP.

> While looking at this, I'm surprised to notice has_cmd() actually
> *runs* the command by calling run_cmd(). I'd have expected it solely
> checks for binary presence and RX perms, avoiding unexpected side
> effects.

It uses "which" to search for the binary ... that could be done better for 
sure (especially since "which" might not be available on all systems), but 
it already was done this way in the Avocado tests, so at least that's not a 
regression.

  Thomas