rules_cc/tests/rule_based_toolchain/variables
Googler e1c7ebb858 Add support for select'ing on cc_args(args=...).
This CL is an alternative to unknown commit. I left the other CL seperately, because I wasn't 100% sure that we'd agree to this, since this is an API change.
I did it this way because I believe it's much less hacky, and it also allows us to format things that aren't variables.

BEGIN_PUBLIC
Add support for select'ing on cc_args(args=...).

This is quite tricky because the one parameter was being split into two in a macro, one of type label and the other of type string.

For example, `args = ["--foo", format_arg("--bar=%s", "//path/to:bar")]` was rewritten by the macro to `args = [json.encode(struct(format_type="raw", format="foo")), json.encode(struct(format_type="format_arg", format="--bar=%s", value=0))], variables = ["//path/to:bar"]`.
To allow it to work with selects, we need to ensure that we don't perform post-processing on the inside of the select. To solve this, we:
* Ensure that args only take strings
* Provide a seperate parameter for substitutions.

This new mechanism also has the useful property that we can now format things that are not variables. For example, I can do the following:

```
directory(name = "sysroot", ...)
cc_args(
    name = "sysroot_arg",
    args = ["--sysroot={sysroot}"],
    format = {
        ":sysroot": "sysroot"
    }
)
```

END_PUBLIC

PiperOrigin-RevId: 656211278
Change-Id: If83f1ea5a99090c18f2a561c51ec6d39ce9fe419
2024-07-25 20:13:42 -07:00
..
BUILD Add support for select'ing on cc_args(args=...). 2024-07-25 20:13:42 -07:00
variables_test.bzl Implement flag_group in the new rule-based toolchain. 2024-04-05 01:47:45 -07:00