feat(poly check): report unused bricks in projects (#360)

* feat(check): collect unused bricks in a project

* feat(check): print unused bricks in a project

* feat(check): report unused bricks when running in strict mode

* bump Poetry plugin to 1.39.0

* bump CLI to 1.32.0

* test(check): add tests for the collect unused bricks function

Author: DavidVujic

components/polylith/check/collect.py

@@ -37,12 +37,35 @@ def diff(known_bricks: Set[str], bases: Set[str], components: Set[str]) -> Set[s
     return known_bricks.difference(bricks)
 
 
+def flatten_imported_bricks(imports: dict) -> Set[str]:
+    return set().union(*imports.values())
+
+
+def to_flattened_imports(brick_imports: dict) -> Set[str]:
+    flattened_bases = flatten_imported_bricks(brick_imports["bases"])
+    flattened_components = flatten_imported_bricks(brick_imports["components"])
+
+    return set().union(flattened_bases, flattened_components)
+
+
 def imports_diff(
     brick_imports: dict, bases: Set[str], components: Set[str]
 ) -> Set[str]:
-    flattened_bases = set().union(*brick_imports["bases"].values())
-    flattened_components = set().union(*brick_imports["components"].values())
-
-    flattened_imports = set().union(flattened_bases, flattened_components)
+    flattened_imports = to_flattened_imports(brick_imports)
 
     return diff(flattened_imports, bases, components)
+
+
+def is_used(brick: str, imported_bricks: dict) -> bool:
+    return any(k for k, v in imported_bricks.items() if k != brick and brick in v)
+
+
+def find_unused_bricks(
+    brick_imports: dict, bases: Set[str], components: Set[str]
+) -> Set[str]:
+    all_brick_imports = {**brick_imports["bases"], **brick_imports["components"]}
+
+    bricks = to_flattened_imports(brick_imports).difference(bases)
+    used_bricks = {brick for brick in bricks if is_used(brick, all_brick_imports)}
+
+    return components.difference(used_bricks)

components/polylith/check/report.py

@@ -42,7 +42,19 @@ def print_missing_deps(diff: Set[str], project_name: str) -> None:
 
     missing = ", ".join(sorted(diff))
 
-    console.print(f":thinking_face: Cannot locate {missing} in {project_name}")
+    console.print(f":thinking_face: Cannot locate [data]{missing}[/] in [proj]{project_name}[/]")
+
+
+def print_unused_bricks(bricks: Set[str], project_name: str) -> None:
+    if not bricks:
+        return
+
+    console = Console(theme=theme.poly_theme)
+
+    unused = ", ".join(sorted(bricks))
+    verb = "Are" if len(bricks) > 1 else "Is"
+
+    console.print(f":mag_right: {verb} [comp]{unused}[/] needed in [proj]{project_name}[/]?")
 
 
 def collect_all_imports(root: Path, ns: str, project_data: dict) -> dict:
@@ -85,9 +97,12 @@ def create_report(
         third_party_imports, third_party_libs, is_strict
     )
 
+    unused_bricks = collect.find_unused_bricks(brick_imports, bases, components)
+
     return {
         "brick_imports": brick_imports,
         "third_party_imports": third_party_imports,
         "brick_diff": brick_diff,
         "libs_diff": libs_diff,
+        "unused_bricks": unused_bricks,
     }

components/polylith/commands/check.py

@@ -106,6 +106,9 @@ def run_each(
         check.report.print_missing_deps(details["brick_diff"], name)
         check.report.print_missing_deps(details["libs_diff"], name)
 
+    if is_strict and not is_quiet:
+        check.report.print_unused_bricks(details["unused_bricks"], name)
+
     return res, details
 
 

projects/poetry_polylith_plugin/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "poetry-polylith-plugin"
-version = "1.38.2"
+version = "1.39.0"
 description = "A Poetry plugin that adds tooling support for the Polylith Architecture"
 authors = ["David Vujic"]
 homepage = "https://davidvujic.github.io/python-polylith-docs/"

projects/polylith_cli/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "polylith-cli"
-version = "1.31.3"
+version = "1.32.0"
 description = "Python tooling support for the Polylith Architecture"
 authors = ['David Vujic']
 homepage = "https://davidvujic.github.io/python-polylith-docs/"

test/components/polylith/check/__init__.py

@@ -0,0 +1,29 @@
+from polylith.check import collect
+
+brick_imports = {
+    "bases": {"base_one": {"base_one", "component_one"}},
+    "components": {
+        "component_one": {"component_one", "component_two", "component_tree"},
+        "component_two": {"component_two"},
+        "component_three": {"component_three"},
+    },
+}
+
+bases = {"base_one"}
+
+
+def test_find_unused_bricks_returns_no_unused_bricks():
+    components = {"component_one", "component_two", "component_tree"}
+
+    res = collect.find_unused_bricks(brick_imports, bases, components)
+
+    assert res == set()
+
+
+def test_find_unused_bricks_returns_unused_bricks():
+    expected = {"component_four"}
+    components = set().union({"component_one", "component_two"}, expected)
+
+    res = collect.find_unused_bricks(brick_imports, bases, components)
+
+    assert res == expected