zmake: Track project inheritance in ProjectConfig

Add an `inherited_from` list field to the ProjectConfig dataclass that
tracks what project(s) the current project inherited from. When using
the `.variant()` project resgistration method, `inherited_from` is
automatically appended with the base project's name. When the following
`BUILD.py` file is processed...

```
baseboard = register_raw_project(project_name="base")
variant1 = baseboard.variant(project_name="variant1")
variant2 = variant1.variant(project_name="variant2")
```

... variant1's `config.inherited_from` field will be `['base']` and
variant2's will be `['base','variant1'].

It is also possible to manually specify `inherited_from` when
registering a project (either as a string or list of strings):

```
register_raw_project(
    project_name="myboard",
    inherited_from=["root","baseboard1"],
)
```

This method is how the EC's `BUILD.py` files are configured.

In either case, the project's full name can be accessed by reading the
ProjectConfig object's `full_name` property to join the names of the
parent boards plus the current project name. In the case of the above
example, the property would read `"root.baseboard1.myboard"`.

The full name is not consumed anywhere within zmake; it is intended to
be used for external reporting tools and does not affect the builds.

BRANCH=None
BUG=b:276947804
TEST=zephyr/zmake/run_tests.sh

Change-Id: I7d7413175c9c670a64e7ade01a41e46a2fb8d743
Signed-off-by: Tristan Honscheid <honscheid@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4400532
Reviewed-by: Jeremy Bettis <jbettis@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>

1 files changed, 19 insertions, 1 deletions

diff --git a/zephyr/zmake/zmake/project.py b/zephyr/zmake/zmake/project.py
index 3c18520b55..2c91e27ba7 100644
--- a/zephyr/zmake/zmake/project.py
+++ b/zephyr/zmake/zmake/project.py
@@ -52,6 +52,20 @@ class ProjectConfig:
         default_factory=list
     )
     project_dir: pathlib.Path = dataclasses.field(default_factory=pathlib.Path)
+    inherited_from: typing.Iterable[str] = dataclasses.field(
+        default_factory=list
+    )
+
+    @property
+    def full_name(self) -> str:
+        """Get the full project name, e.g. baseboard.variant"""
+        inherited_from = (
+            [self.inherited_from]
+            if isinstance(self.inherited_from, str)
+            else self.inherited_from
+        )
+
+        return ".".join([*inherited_from, self.project_name])
 
 
 class Project:
@@ -198,12 +212,16 @@ class ProjectRegistrationHandler:
             Another ProjectRegistrationHandler.
         """
         new_config = dataclasses.asdict(self.base_config)
+        new_config["inherited_from"] = [
+            *self.base_config.inherited_from,
+            self.base_config.project_name,
+        ]
+
         for key, value in kwargs.items():
             if isinstance(value, list):
                 new_config[key] = [*new_config[key], *value]
             else:
                 new_config[key] = value
-
         return self.register_func(**new_config)