From 4af390e763395f58f336107a6d3322da1a5d3f5f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20G=C3=B3rny?= <mgorny@gentoo.org>
Date: Mon, 6 Jan 2025 22:04:18 +0000
Subject: [PATCH] Allow and validate `schema_version` key in v1 recipes (#2207)

* Accept `schema_version` key in v1 recipes

Allow the v1 recipes to contain a top-level `schema_version` key,
and expect it to be ordered first.  The key is defined in CEP 14:
https://conda.org/learn/ceps/cep-0014#schema-version

Fixes #2201

* Add `schema_version` validation

For the time being, just verify that `schema_version` is 1 when using
`recipe.yaml` format, and refuse to lint if it is not.  In the future,
the code will probably need to be adapted to change `recipe_version`
based on `schema_version`.

* Add a news entry

---------

Co-authored-by: Matthew R. Becker <beckermr@users.noreply.github.com>
---
 conda_smithy/lint_recipe.py                   |  8 +++++++
 conda_smithy/linter/conda_recipe_v1_linter.py |  2 ++
 news/schema_version.rst                       | 23 +++++++++++++++++++
 tests/recipes/v1_recipes/torchvision.yaml     |  2 ++
 tests/test_lint_recipe.py                     | 17 ++++++++++++++
 5 files changed, 52 insertions(+)
 create mode 100644 news/schema_version.rst

diff --git a/conda_smithy/lint_recipe.py b/conda_smithy/lint_recipe.py
index 8d633fa6d..2395b97a5 100644
--- a/conda_smithy/lint_recipe.py
+++ b/conda_smithy/lint_recipe.py
@@ -126,6 +126,14 @@ def lintify_meta_yaml(
     recipe_name = "meta.yaml" if recipe_version == 0 else "recipe.yaml"
     recipe_fname = os.path.join(recipe_dir or "", recipe_name)
 
+    if recipe_version == 1:
+        schema_version = meta.get("schema_version", 1)
+        if schema_version != 1:
+            lints.append(
+                f"Unsupported recipe.yaml schema version {schema_version}"
+            )
+            return lints, hints
+
     sources_section = get_section(meta, "source", lints, recipe_version)
     build_section = get_section(meta, "build", lints, recipe_version)
     requirements_section = get_section(
diff --git a/conda_smithy/linter/conda_recipe_v1_linter.py b/conda_smithy/linter/conda_recipe_v1_linter.py
index 1a5792e2a..27746227c 100644
--- a/conda_smithy/linter/conda_recipe_v1_linter.py
+++ b/conda_smithy/linter/conda_recipe_v1_linter.py
@@ -15,6 +15,7 @@
 REQUIREMENTS_ORDER = ["build", "host", "run"]
 
 EXPECTED_SINGLE_OUTPUT_SECTION_ORDER = [
+    "schema_version",
     "context",
     "package",
     "source",
@@ -26,6 +27,7 @@
 ]
 
 EXPECTED_MULTIPLE_OUTPUT_SECTION_ORDER = [
+    "schema_version",
     "context",
     "recipe",
     "source",
diff --git a/news/schema_version.rst b/news/schema_version.rst
new file mode 100644
index 000000000..cebb8be36
--- /dev/null
+++ b/news/schema_version.rst
@@ -0,0 +1,23 @@
+**Added:**
+
+* Added validation for ``schema_version`` key. (#2207)
+
+**Changed:**
+
+* <news item>
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* ``schema_version`` key no longer causes linting failures. (#2207)
+
+**Security:**
+
+* <news item>
diff --git a/tests/recipes/v1_recipes/torchvision.yaml b/tests/recipes/v1_recipes/torchvision.yaml
index 0f943464b..b9dc9a97d 100644
--- a/tests/recipes/v1_recipes/torchvision.yaml
+++ b/tests/recipes/v1_recipes/torchvision.yaml
@@ -1,3 +1,5 @@
+schema_version: 1
+
 context:
   version: 0.20.1
   build_number: 2
diff --git a/tests/test_lint_recipe.py b/tests/test_lint_recipe.py
index 33d93e745..06bdfe550 100644
--- a/tests/test_lint_recipe.py
+++ b/tests/test_lint_recipe.py
@@ -3865,5 +3865,22 @@ def test_lint_recipe_parses_v1_duplicate_keys():
         ), hints
 
 
+def test_lint_recipe_v1_invalid_schema_version():
+    with tempfile.TemporaryDirectory() as tmpdir:
+        with open(os.path.join(tmpdir, "recipe.yaml"), "w") as f:
+            f.write(
+                textwrap.dedent(
+                    """
+                    schema_version: 2
+
+                    package:
+                      name: blah
+                    """
+                )
+            )
+        lints, hints = linter.main(tmpdir, return_hints=True, conda_forge=True)
+        assert lints == ["Unsupported recipe.yaml schema version 2"]
+
+
 if __name__ == "__main__":
     unittest.main()