Re: [bitbake-devel] [PATCH 1/2] bitbake: data_smart: fix ??= operator for getVarFlags

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2025-02-12 at 13:16 +0100, Louis Rannou via lists.openembedded.org wrote:
> From: Louis Rannou <louis.rannou@non.se.com>
> 
> Variable flags have been fixed in commit
> 0329a7e3ac694737f2d2c1861f65492551360663 which introduces the
> "_defaultval_flag_" prefix for default values. This must not be ignored as
> others "_"-prefixed flags names.
> 
> Split the processing of default values to be sure they are overwritted by the
> others operators disregarding of their order.
> 
> Fixes [YOCTO #15685]
> 
> Signed-off-by: Louis Rannou <louis.rannou@non.se.com>
> ---
>  lib/bb/data_smart.py | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/lib/bb/data_smart.py b/lib/bb/data_smart.py
> index 897ceeb32c7ce0acb8ed44c25e1bf2f2f28aa9dc..7663f28c5071a77c8452c1016e5ee0d969c84bec 100644
> --- a/lib/bb/data_smart.py
> +++ b/lib/bb/data_smart.py
> @@ -952,12 +952,22 @@ class DataSmart(MutableMapping):
>      def getVarFlags(self, var, expand = False, internalflags=False):
>          local_var = self._findVar(var)
>          flags = {}
> +        flags_set = {}
>  
>          if local_var:
> -            for i in local_var:
> -                if i.startswith(("_", ":")) and not internalflags:
> +            for i, val in local_var.items():
> +                if i.startswith("_defaultval_flag_"):
> +                    i = i[len("_defaultval_flag_"):]
> +                    flags[i] = val
> +                elif i.startswith(("_", ":")) and not internalflags:
>                      continue
> -                flags[i] = local_var[i]
> +                else:
> +                    flags_set[i] = val
> +
> +            # Flags sets take over defaults
> +            flags.update(flags_set)
> +
> +            for i in flags:
>                  if expand and i in expand:
>                      flags[i] = self.expand(flags[i], var + "[" + i + "]")
>          if len(flags) == 0:
> 

I've not gone into the details but this doesn't look right at all
unfortunately. It looks over complicated, it is special casing magic
values which we try very very hard not to do and I don't think this is
going to be maintainable code. We're need to find a better solution.
Without diving into the code I'm going to struggle to provide better
advice though.

Cheers,

Richard