feat: add a new 'files_changed' parameter

Author: ahal

docs/reference/parameters.rst

@@ -45,6 +45,10 @@ head_tag
 ~~~~~~~~
    The tag attached to the revision, if any.
 
+files_changed
+~~~~~~~~~~~~~
+   The list of all files added or modified by the push.
+
 owner
 ~~~~~
    Email address indicating the person who made the push. Note that this

src/taskgraph/decision.py

@@ -185,6 +185,7 @@ def get_decision_parameters(graph_config, options):
 
     # Define default filter list, as most configurations shouldn't need
     # custom filters.
+    parameters["files_changed"] = repo.get_changed_files("AM")
     parameters["filters"] = [
         "target_tasks_method",
     ]

src/taskgraph/parameters.py

@@ -40,6 +40,7 @@ class ParameterMismatch(Exception):
         Required("do_not_optimize"): [str],
         Required("enable_always_target"): Any(bool, [str]),
         Required("existing_tasks"): {str: str},
+        Required("files_changed"): [str],
         Required("filters"): [str],
         Required("head_ref"): str,
         Required("head_repository"): str,
@@ -86,6 +87,7 @@ def _get_defaults(repo_root=None):
         # Use fake values if no repo is detected.
         repo = Mock(branch="", head_rev="", tool="git")
         repo.get_url.return_value = ""
+        repo.get_changed_files.return_value = []
 
     try:
         repo_url = repo.get_url()
@@ -108,6 +110,7 @@ def _get_defaults(repo_root=None):
         "do_not_optimize": [],
         "enable_always_target": True,
         "existing_tasks": {},
+        "files_changed": repo.get_changed_files("AM"),
         "filters": ["target_tasks_method"],
         "head_ref": repo.branch or repo.head_rev,
         "head_repository": repo_url,

taskcluster/test/params/main-repo-pull-request-untrusted.yml

@@ -3,6 +3,9 @@ base_repository: https://github.com/ahal/taskgraph
 build_date: 1650573119
 do_not_optimize: []
 existing_tasks: {}
+files_changed:
+    - src/taskgraph/decision.py
+    - test/test_decision.py
 filters:
     - target_tasks_method
 head_ref: 2695ccc00b55efc92b823e91c03120cec04c6d50

taskcluster/test/params/main-repo-pull-request.yml

@@ -3,6 +3,9 @@ base_repository: https://github.com/ahal/taskgraph
 build_date: 1650573119
 do_not_optimize: []
 existing_tasks: {}
+files_changed:
+    - src/taskgraph/decision.py
+    - test/test_decision.py
 filters:
     - target_tasks_method
 head_ref: 2695ccc00b55efc92b823e91c03120cec04c6d50

taskcluster/test/params/main-repo-push.yml

@@ -3,6 +3,9 @@ base_repository: https://github.com/taskcluster/taskgraph
 build_date: 1650566877
 do_not_optimize: []
 existing_tasks: {}
+files_changed:
+    - src/taskgraph/decision.py
+    - test/test_decision.py
 filters:
     - target_tasks_method
 head_ref: d0bcf5ac346b3d6037fdcdaf23657593b18e1f18

taskcluster/test/params/main-repo-release.yml

@@ -7,6 +7,9 @@ build_number: 1
 do_not_optimize: []
 enable_always_target: true
 existing_tasks: {}
+files_changed:
+  - src/taskgraph/decision.py
+  - test/test_decision.py
 filters:
   - target_tasks_method
 head_ref: release-test

test/fixtures/gen.py

@@ -139,6 +139,7 @@ def parameters():
             "build_date": 0,
             "build_number": 1,
             "enable_always_target": True,
+            "files_changed": [],
             "head_repository": "http://hg.example.com",
             "head_rev": "abcdef",
             "head_ref": "default",

test/test_parameters.py

@@ -37,6 +37,7 @@ class TestParameters(TestCase):
         "do_not_optimize": [],
         "enable_always_target": True,
         "existing_tasks": {},
+        "files_changed": [],
         "filters": ["target_tasks_method"],
         "head_ref": "ref",
         "head_repository": "repository",
@@ -298,6 +299,7 @@ def test_extend_parameters_schema(monkeypatch):
                 "do_not_optimize": [],
                 "enable_always_target": True,
                 "existing_tasks": {},
+                "files_changed": ["foo.txt"],
                 "filters": ["target_tasks_method"],
                 "head_ref": "some-branch",
                 "head_repository": "https://some.url",
@@ -332,6 +334,7 @@ def test_extend_parameters_schema(monkeypatch):
                 "do_not_optimize": [],
                 "enable_always_target": True,
                 "existing_tasks": {},
+                "files_changed": ["foo.txt"],
                 "filters": ["target_tasks_method"],
                 "head_ref": "some-branch",
                 "head_repository": "https://some.url",
@@ -366,6 +369,7 @@ def test_extend_parameters_schema(monkeypatch):
                 "do_not_optimize": [],
                 "enable_always_target": True,
                 "existing_tasks": {},
+                "files_changed": ["foo.txt"],
                 "filters": ["target_tasks_method"],
                 "head_ref": "some-branch",
                 "head_repository": "",
@@ -400,6 +404,7 @@ def test_extend_parameters_schema(monkeypatch):
                 "do_not_optimize": [],
                 "enable_always_target": True,
                 "existing_tasks": {},
+                "files_changed": [],
                 "filters": ["target_tasks_method"],
                 "head_ref": "",
                 "head_repository": "",
@@ -434,6 +439,7 @@ def mock_get_repository(repo_root):
                 tool="git",
             )
             repo_mock.get_url.return_value = "https://some.url"
+            repo_mock.get_changed_files.return_value = ["foo.txt"]
             return repo_mock
 
         raise RuntimeError