Add a yaml linting subcommand (#1023)

Co-authored-by: Andreas Kloeckner <[email protected]>

pyproject.toml

@@ -172,6 +172,8 @@ types-PyYAML = "^0.1.5"
 # tests for code questions use question code that has numpy
 numpy = "^1.19"
 
+yamllint = "^1.32.0"
+
 # enable with "-E postgres"
 [tool.poetry.extras]
 postgres = ["psycopg2"]

relate/bin/relate.py

@@ -91,8 +91,49 @@ def expand_yaml(yml_file, repo_root):
 # }}}
 
 
-# {{{ code test
+# {{{ lint YAML
+def lint_yaml(args):
+    import os
+
+    from yamllint import linter
+    from yamllint.cli import show_problems
+    from yamllint.config import YamlLintConfig
+
+    conf = YamlLintConfig(file=args.config_file)
+
+    had_problems = False
+
+    def check_file(name):
+        nonlocal had_problems
+
+        # expanded yaml is missing a newline at the end of the
+        # file which causes the linter to complain, so we add a
+        # newline :)
+        expanded_yaml = expand_yaml(name, args.repo_root) + "\n"
+
+        problems = list(linter.run(expanded_yaml, conf))
+        show_problems(problems, name, "auto", None)
+
+        had_problems = had_problems or bool(problems)
 
+    for item in args.files:
+        if os.path.isdir(item):
+            for root, _, filenames in os.walk(item):
+                for f in filenames:
+                    filepath = os.path.join(root, f)
+                    if not conf.is_file_ignored(f) and conf.is_yaml_file(f):
+                        check_file(filepath)
+        else:
+            check_file(item)
+
+    print(f"{had_problems=}")
+
+    return int(had_problems)
+
+# }}}
+
+
+# {{{ code test
 def test_code_question(page_desc, repo_root) -> bool:
     if page_desc.type not in [
             "PythonCodeQuestion",
@@ -305,6 +346,14 @@ def main() -> None:
     parser_expand_yaml.add_argument("YAML_FILE")
     parser_expand_yaml.set_defaults(func=expand_yaml_ui)
 
+    parser_lint_yaml = subp.add_parser("lint-yaml")
+    parser_lint_yaml.add_argument("--repo-root", default=os.getcwd())
+    parser_lint_yaml.add_argument("--config-file", default="./.yamllint")
+    parser_lint_yaml.add_argument("files", metavar="FILES",
+                                  nargs="+",
+                                  help="List of directories or files to lint")
+    parser_lint_yaml.set_defaults(func=lint_yaml)
+
     args = parser.parse_args()
 
     if not hasattr(args, "func"):

tests/test_lint_yaml/.yamllint.yml

@@ -0,0 +1,11 @@
+extends: default
+rules:
+  line-length:
+    max: 200
+    level: warning
+  document-start: disable
+  indentation: disable
+  empty-lines: disable
+  commas: disable
+  hyphens: disable
+  comments: disable

tests/test_lint_yaml/fail.yml

@@ -0,0 +1,6 @@
+extends: default
+
+rules:
+  line-length:
+    max: 200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+      bad

tests/test_lint_yaml/pass.yml

@@ -0,0 +1,11 @@
+extends: default
+rules:
+  line-length:
+    max: 200
+    level: warning
+  document-start: disable
+  indentation: disable
+  empty-lines: disable
+  commas: disable
+  hyphens: disable
+  comments: disable

tests/test_lint_yaml/test_lint_yaml.py

@@ -0,0 +1,20 @@
+import os
+import sys
+
+import pytest
+
+
+@pytest.mark.parametrize("yaml_file", ["pass.yml", "fail.yml"])
+def test_yaml_lint(yaml_file):
+    from subprocess import Popen
+    thisdir = os.path.dirname(os.path.realpath(__file__))
+    stream = Popen([sys.executable, "-m", "relate", "lint-yaml",
+                    "--config-file",
+                    os.path.join(thisdir, ".yamllint.yml"),
+                    os.path.join(thisdir, yaml_file)])
+    stream.wait()
+
+    if stream.returncode and "pass" in yaml_file:
+        raise Exception("File that was supposed to pass did not pass")
+    elif stream.returncode == 0 and "fail" in yaml_file:
+        raise Exception("File that was supposed to fail did not fail")