From 727cdd610162b72e90fb9c9043fced9c76490af9 Mon Sep 17 00:00:00 2001
From: Andrew Halberstadt <ahal@mozilla.com>
Date: Thu, 17 Oct 2024 13:24:01 -0400
Subject: [PATCH] fix(transforms.run): be more specific about implicit files
 changed for 'when' optimization

---
 src/taskgraph/transforms/run/__init__.py |  4 ++-
 test/test_transforms_run.py              | 39 ++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/src/taskgraph/transforms/run/__init__.py b/src/taskgraph/transforms/run/__init__.py
index c2ad5cd1..520cdf0a 100644
--- a/src/taskgraph/transforms/run/__init__.py
+++ b/src/taskgraph/transforms/run/__init__.py
@@ -121,7 +121,9 @@ def rewrite_when_to_optimization(config, tasks):
         files_changed = when.get("files-changed")
 
         # implicitly add task config directory.
-        files_changed.append(f"{config.path}/**")
+        files_changed.append(f"{config.path}/kind.yml")
+        if task.get("task-from") and task["task-from"] != "kind.yml":
+            files_changed.append(f"{config.path}/{task['task-from']}")
 
         # "only when files changed" implies "skip if files have not changed"
         task["optimization"] = {"skip-unless-changed": files_changed}
diff --git a/test/test_transforms_run.py b/test/test_transforms_run.py
index a0e102fd..820f0ed2 100644
--- a/test/test_transforms_run.py
+++ b/test/test_transforms_run.py
@@ -86,6 +86,45 @@ def test_worker_caches(task, transform):
     validate_schema(partial_schema, taskdesc["worker"][key], "validation error")
 
 
+def test_rewrite_when_to_optimization(run_transform, make_transform_config):
+    config = make_transform_config()
+
+    task = {"foo": "bar"}
+    result = run_transform(run.rewrite_when_to_optimization, task)
+    assert list(result) == [{"foo": "bar"}]
+
+    task = {"foo": "bar", "when": {"files-changed": ["README.md"]}}
+    result = run_transform(run.rewrite_when_to_optimization, task)
+    assert list(result) == [
+        {
+            "foo": "bar",
+            "optimization": {
+                "skip-unless-changed": ["README.md", f"{config.path}/kind.yml"]
+            },
+        }
+    ]
+
+    task = {
+        "foo": "bar",
+        "when": {"files-changed": ["README.md"]},
+        "task-from": "foo.yml",
+    }
+    result = run_transform(run.rewrite_when_to_optimization, task)
+    assert list(result) == [
+        {
+            "foo": "bar",
+            "optimization": {
+                "skip-unless-changed": [
+                    "README.md",
+                    f"{config.path}/kind.yml",
+                    f"{config.path}/foo.yml",
+                ]
+            },
+            "task-from": "foo.yml",
+        }
+    ]
+
+
 def assert_use_fetches_toolchain_env(task):
     assert task["worker"]["env"]["FOO"] == "1"