zephyr: zmake: Add a list-projects subcommand

Prior to converting to the BUILD.py format, it was possible to find
all projects Zmake supports simply by searching for zmake.yaml
files (e.g., with "find -name zmake.yaml").

Now that Zmake has a more complex project config format, and a single
BUILD.py file may expose multiple projects, we need to expose on the
CLI a way to print out all projects.

BUG=b:193815337
BRANCH=none
TEST=Provided unit tests pass

Signed-off-by: Jack Rosenthal <jrosenth@chromium.org>
Change-Id: Ie726f35f9044b3d5baf782e5e22c9405c35ce1f7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3309360
Reviewed-by: Jeremy Bettis <jbettis@chromium.org>

3 files changed, 102 insertions, 0 deletions

diff --git a/zephyr/zmake/tests/test_zmake.py b/zephyr/zmake/tests/test_zmake.py
index f735d942ed..83862ce65d 100644
--- a/zephyr/zmake/tests/test_zmake.py
+++ b/zephyr/zmake/tests/test_zmake.py
@@ -13,6 +13,7 @@ import unittest
 import unittest.mock as mock
 from unittest.mock import patch
 
+import pytest
 from testfixtures import LogCapture
 
 import zmake.build_config
@@ -228,5 +229,71 @@ class TestFilters(unittest.TestCase):
         assert "devicetree error: 'adc' is marked as required" in list(dt_errs)[0]
 
 
+@pytest.mark.parametrize(
+    ["project_names", "format", "search_dir", "expected_output"],
+    [
+        (
+            ["link", "samus"],
+            "{config.project_name}\n",
+            None,
+            "link\nsamus\n",
+        ),
+        (
+            ["link", "samus"],
+            "{config.project_name}\n",
+            pathlib.Path("/foo/bar"),
+            "link\nsamus\n",
+        ),
+        (
+            [],
+            "{config.project_name}\n",
+            None,
+            "",
+        ),
+        (
+            ["link"],
+            "",
+            None,
+            "",
+        ),
+        (
+            ["link"],
+            "{config.zephyr_board}\n",
+            None,
+            "some_board\n",
+        ),
+        (
+            ["link"],
+            "{config.project_name} is_test={config.is_test}\n",
+            None,
+            "link is_test=False\n",
+        ),
+    ],
+)
+def test_list_projects(project_names, format, search_dir, expected_output, capsys):
+    """Test listing projects with default directory."""
+    fake_projects = {
+        name: zmake.project.Project(
+            zmake.project.ProjectConfig(
+                project_name=name,
+                zephyr_board="some_board",
+                supported_toolchains=["coreboot-sdk"],
+                output_packer=zmake.output_packers.RawBinPacker,
+            )
+        )
+        for name in project_names
+    }
+    zmk = zm.Zmake()
+    with mock.patch(
+        "zmake.project.find_projects",
+        autospec=True,
+        return_value=fake_projects,
+    ):
+        zmk.list_projects(format=format, search_dir=search_dir)
+
+    captured = capsys.readouterr()
+    assert captured.out == expected_output
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/zephyr/zmake/zmake/__main__.py b/zephyr/zmake/zmake/__main__.py
index aef897d1d3..558ca23555 100644
--- a/zephyr/zmake/zmake/__main__.py
+++ b/zephyr/zmake/zmake/__main__.py
@@ -220,6 +220,25 @@ def main(argv=None):
         help="Exit with code 2 if warnings are detected",
     )
 
+    list_projects = sub.add_parser(
+        "list-projects",
+        help="List projects known to zmake.",
+    )
+    list_projects.add_argument(
+        "--format",
+        default="{config.project_name}\n",
+        help=(
+            "Output format to print projects (str.format(config=project.config) is "
+            "called on this for each project)."
+        ),
+    )
+    list_projects.add_argument(
+        "search_dir",
+        type=pathlib.Path,
+        nargs="?",
+        help="Optional directory to search for BUILD.py files in.",
+    )
+
     test = sub.add_parser("test")
     test.add_argument(
         "build_dir",
diff --git a/zephyr/zmake/zmake/zmake.py b/zephyr/zmake/zmake/zmake.py
index d2559a9270..713c6773e3 100644
--- a/zephyr/zmake/zmake/zmake.py
+++ b/zephyr/zmake/zmake/zmake.py
@@ -810,3 +810,19 @@ class Zmake:
             if proc.wait():
                 raise OSError(get_process_failure_msg(proc))
             return 0
+
+    def list_projects(self, format, search_dir):
+        """List project names known to zmake on stdout.
+
+        Args:
+            format: The formatting string to print projects with.
+            search_dir: Directory to start the search for
+                BUILD.py files at.
+        """
+        if not search_dir:
+            search_dir = self.module_paths["ec"] / "zephyr"
+
+        for project in zmake.project.find_projects(search_dir).values():
+            print(format.format(config=project.config), end="")
+
+        return 0