Escape default arrays and sequences the same other default values

[jacobperron]

Fixes #610

[jacobperron]

As a regression test, I've added a new field to one of the test messages: ros2/test_interface_files#16

[jacobperron]

• Linux
• Linux-aarch64
• macOS
• Windows

[jacobperron]

Rpr fails because ament/ament_cmake#352 has not been released.

[sloretz]

This is interesting. I can't predict if it will pass the test_communication tests. I recommend adding another test to test_interface_files with "ハローワールド" to see what it does when given a string with characters outside the latin-1 character set.

https://github.com/ros2/test_interface_files/blob/ea4d4f33eca97f37b4294e6ab012fa0f216de609/msg/WStrings.msg#L2-L4

IIUC Hellö wörld!" in that .msg file is encoded as the UTF-8 bytes b'Hell\xc3\xb6 w\xc3\xb6rld!'. When read as latin-1 the string in Python would be very different from the original.

>>> b'Hell\xc3\xb6 w\xc3\xb6rld!'.decode('latin-1')
'Hellö wörld!'

When re-encoded as latin-1 that should output the original bytes, but there's some more weirdness when the generators read the idl files.

rosidl/rosidl_parser/rosidl_parser/parser.py

Line 660 in 36ed120

return codecs.decode(match.group(0), 'unicode-escape')

[jacobperron]

IIUC Hellö wörld!" in that .msg file is encoded as the UTF-8 bytes b'Hell\xc3\xb6 w\xc3\xb6rld!'. When read as latin-1 the string in Python would be very different from the original.

In fact there were test failures related to this that I missed locally: https://ci.ros2.org/job/ci_linux/15332/testReport/junit/rosidl_generator_py.test/test_interfaces/test_wstrings/

[jacobperron]

I think the issue was due to a difference in how we handled default values of arrays and sequences compared with other default values. See 8253770, which applies similar logic to array/sequence defaults as we do with other defaults, e.g.

rosidl/rosidl_adapter/rosidl_adapter/msg/__init__.py

Lines 78 to 79 in 36ed120

	estr = string.encode().decode('unicode_escape')
	estr = estr.replace('"', r'\"')

• Linux
• Linux-aarch64
• macOS
• Windows