[gha] deprecate set-output for determinator

.github/workflows/check-minimum-revision.yaml

@@ -42,7 +42,7 @@ jobs:
           FAILED=$?
           set -e
 
-          echo "::set-output name=FAIL_MERGE_BASE::$FAILED"
+          echo "FAIL_MERGE_BASE=${FAILED}" >> $GITHUB_OUTPUT
           MERGE_BASE="$(git merge-base origin/main ${{ env.GIT_SHA }})"
 
           if [[ $FAILED == 1 ]]; then

testsuite/determinator.py

@@ -5,6 +5,7 @@
 from typing import Generic, Optional, Sequence, Tuple, TypeVar, TypedDict
 
 import click
+import os
 
 
 @dataclass
@@ -75,11 +76,26 @@ def main() -> None:
 
 @dataclass
 class GithubOutput:
+    """
+    Represents a Github Output string
+    It should be written separately to $GITHUB_OUTPUT in the action: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/
+    """
+
     key: str
     value: str
 
     def format(self) -> str:
-        return f"::set-output name={self.key}::{self.value}"
+        return f"{self.key}={self.value}"
+
+
+def write_github_output(output: GithubOutput) -> None:
+    try:
+        with open(os.environ["GITHUB_OUTPUT"], "a") as f:
+            f.write(f"{output.format()}\n")
+    except KeyError:
+        raise Exception(
+            "GITHUB_OUTPUT not set, not writing output. This may be an error with the action setup."
+        )
 
 
 @main.command()
@@ -101,6 +117,7 @@ def changed_files(
 
     if github_output_key:
         output = GithubOutput(github_output_key, "true" if verdict.verdict else "false")
+        write_github_output(output)
         print(output.format())
     else:
         if not verdict.verdict:

testsuite/determinator_test.py

@@ -1,9 +1,21 @@
 import unittest
+import tempfile
+import os
 
 from click.testing import CliRunner
 from determinator import main, ChangedFilesPredicate, ChangedFilesContext
 
 
+# If this test is run from Github Actions, $GITHUB_OUTPUT will be set
+# Otherwise, create a tempfile for it, which exists for the duration of the test
+if "GITHUB_OUTPUT" not in os.environ:
+    temp_github_output = tempfile.NamedTemporaryFile(
+        prefix="determinator_github_output_"
+    )
+    os.environ["GITHUB_OUTPUT"] = temp_github_output.name
+print("GITHUB_OUTPUT set to", os.environ["GITHUB_OUTPUT"])
+
+
 class ChangedFilesPredicateTestCase(unittest.TestCase):
     def test_changed_files_passes(self) -> None:
         context: ChangedFilesContext = {"changed_files": ["asdf"]}
@@ -33,7 +45,7 @@ def test_determinator_from_github(self) -> None:
         )
         self.assertEqual(
             result.output,
-            "FAILED because Matched files: []\n" "::set-output name=BANANA::false\n",
+            "FAILED because Matched files: []\n" "BANANA=false\n",
         )
         self.assertEqual(result.exit_code, 0)
 
@@ -55,6 +67,6 @@ def test_determinator_from_github_passes(self) -> None:
             result.output,
             "PASSED because Matched files: "
             "['testsuite/fixtures/helm/banana.ts']\n"
-            "::set-output name=BANANA::true\n",
+            "BANANA=true\n",
         )
         self.assertEqual(result.exit_code, 0)