[Scons-users] Environment clones linked?

[Jonathon Reinhart]

We've fought this exact issue before as well: Modifications to Actions
or ActionLists affect all environments.

The key, as Bill explained, is to leverage the indirection that the
environments provide via the  *COM variables. In our case, we actually
append to the action lists in the environments.


Jonathon

On Fri, May 25, 2018 at 12:23 AM, Daniel Moody <dmoody256 at gmail.com> wrote:
> Thanks that worked!
>
> I didn't understand how deep Clone went. Originally I tried to modify the
> Action command directly because I didn't want to mess with the other actions
> for the SHLINKCOM.
>
> On Thu, May 24, 2018 at 11:54 PM, Bill Deegan <bill at baddogconsulting.com>
> wrote:
>>
>> So you're reaching into an Action defined in a builder.
>> That's pretty far inside the Environment to a level that there's not a
>> deep copy of it.
>>
>> This when using mslink right?
>>
>> shlibLinkAction = SCons.Action.Action('${TEMPFILE("$SHLINK $SHLINKFLAGS
>> $_SHLINK_TARGETS $_LIBDIRFLAGS $_LIBFLAGS $_PDB $_SHLINK_SOURCES",
>> "$SHLINKCOMSTR")}', '$SHLINKCOMSTR')
>>
>> regServerAction = SCons.Action.Action("$REGSVRCOM", "$REGSVRCOMSTR")
>>
>> embedManifestDllCheckAction = SCons.Action.Action(embedManifestDllCheck,
>> None)
>>
>> compositeShLinkAction = shlibLinkAction + regServerCheck +
>> embedManifestDllCheckAction
>>
>> env['SHLINKCOM']   =  compositeShLinkAction
>>
>>
>> In this case I'd expect the Clone copy/deep copying logic would yield what
>> you are seeing.
>> If you did this:
>>
>> env2['SHLINKCOM'] = SCons.Action.Action("echo link command env2",None) +
>> env2['SHLINKCOM'].list[1] + env2['SHLINKCOM'].list[2]
>>
>> Then it shouldn't modify env1..
>> -Bill
>>
>>
>> On Thu, May 24, 2018 at 8:33 PM, Daniel Moody <dmoody256 at gmail.com> wrote:
>>>
>>> I am trying to clone an environment and then make changes to the clone so
>>> that it is different than the original.
>>>
>>> But somehow changing the clone also changes my original env? Is that
>>> expected behavior?
>>>
>>> Below is an example SConstruct which reproduces the issue (SCons 3.01
>>> installed from pip on windows 10):
>>>
>>> env1 = Environment()
>>> env2 = env1.Clone()
>>>
>>> print("env2 before = " + env1['SHLINKCOM'].list[0].cmd_list)
>>> env2['SHLINKCOM'].list[0].cmd_list = "echo link command env2"
>>> print("env2 after = " + env1['SHLINKCOM'].list[0].cmd_list)
>>>
>>> print("env1 = " + env2['SHLINKCOM'].list[0].cmd_list)
>>>
>>> Which produces this output:
>>>
>>> C:\Users\Daniel\workspace>scons  -f SConstruct.py
>>> scons: Reading SConscript files ...
>>> env2 before = ${TEMPFILE("$SHLINK $SHLINKFLAGS $_SHLINK_TARGETS
>>> $_LIBDIRFLAGS $_LIBFLAGS $_PDB $_SHLINK_SOURCES", "$SHLINKCOMSTR")}
>>> env2 after = echo link command env2
>>> env1 = echo link command env2
>>> scons: done reading SConscript files.
>>> scons: Building targets ...
>>> scons: `.' is up to date.
>>> scons: done building targets.
>>>
>>> Can someone shed some light on if this is a bug or how do I uniquely
>>> modify the SHLINKCOM?
>>>
>>> _______________________________________________
>>> Scons-users mailing list
>>> Scons-users at scons.org
>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>
>>
>>
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>
>
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