refactor conda-forge.yml linting logic, hint about extra fields

conda_smithy/cli.py

@@ -4,7 +4,6 @@
 import sys
 import time
 import argparse
-import io
 import tempfile
 
 from textwrap import dedent

conda_smithy/configure_feedstock.py

@@ -2697,7 +2697,7 @@ def main(
     import argparse
 
     parser = argparse.ArgumentParser(
-        description=("Configure a feedstock given " "a conda-forge.yml file.")
+        description="Configure a feedstock given a conda-forge.yml file."
     )
     parser.add_argument(
         "forge_file_directory",

conda_smithy/lint_forge_yml.py

@@ -0,0 +1,87 @@
+import json
+from inspect import cleandoc
+from textwrap import indent
+from typing import List
+
+import jsonschema
+from pydantic import BaseModel
+
+from conda_smithy.linting_types import Linter, LintsHints
+from conda_smithy.schema import ConfigModel
+from conda_smithy.validate_schema import validate_json_schema
+
+
+def _format_validation_msg(error: jsonschema.ValidationError):
+    """Use the data on the validation error to generate improved reporting.
+
+    If available, get the help URL from the first level of the JSON path:
+
+        $(.top_level_key.2nd_level_key)
+    """
+    help_url = "https://conda-forge.org/docs/maintainer/conda_forge_yml"
+    path = error.json_path.split(".")
+    descriptionless_schema = {}
+    subschema_text = ""
+
+    if error.schema:
+        descriptionless_schema = {
+            k: v for (k, v) in error.schema.items() if k != "description"
+        }
+
+    if len(path) > 1:
+        help_url += f"""/#{path[1].split("[")[0].replace("_", "-")}"""
+        subschema_text = json.dumps(descriptionless_schema, indent=2)
+
+    return cleandoc(
+        f"""
+        In conda-forge.yml: [`{error.json_path}`]({help_url}) `=` `{error.instance}`.
+{indent(error.message, " " * 12 + "> ")}
+            <details>
+            <summary>Schema</summary>
+
+            ```json
+{indent(subschema_text, " " * 12)}
+            ```
+
+            </details>
+        """
+    )
+
+
+def lint_validate_json(forge_yaml: dict) -> LintsHints:
+    validation_lints, validation_hints = validate_json_schema(forge_yaml)
+
+    lints = [_format_validation_msg(lint) for lint in validation_lints]
+    hints = [_format_validation_msg(hint) for hint in validation_hints]
+
+    return LintsHints(lints, hints)
+
+
+def lint_extra_fields(
+    forge_yaml: dict,
+) -> LintsHints:
+    """
+    Identify unexpected keys in the conda-forge.yml file.
+    This only works if extra="allow" is set in the Pydantic sub-model where the unexpected key is found.
+    """
+
+    config = ConfigModel.model_validate(forge_yaml)
+    hints = []
+
+    def _find_extra_fields(model: BaseModel, prefix=""):
+        for extra_field in (model.__pydantic_extra__ or {}).keys():
+            hints.append(f"Unexpected key {prefix + extra_field}")
+
+        for field, value in model:
+            if isinstance(value, BaseModel):
+                _find_extra_fields(value, f"{prefix + field}.")
+
+    _find_extra_fields(config)
+
+    return LintsHints(hints=hints)
+
+
+FORGE_YAML_LINTERS: List[Linter] = [
+    lint_validate_json,
+    lint_extra_fields,
+]