Implement a YAML linter hook

README.md

@@ -13,6 +13,8 @@ Repository to develop **experimental** [Conan](https://conan.io) hooks for Conan
  * [Member typo checker](#members-typo-checker)
  * [SPDX checker](#spdx-checker)
  * [Recipe linter](#recipe-linter)
+ * [Non ASCII](#non-ascii)
+ * [YAML linter](#yaml-linter)
 
 
 ## Hook setup
@@ -176,6 +178,14 @@ Separate KB-H047 from Conan Center, which is no longer required due Python 2.7 d
 
 Validates if `conanfile.py` and `test_package/conanfile.py` contain a non-ascii present, when there is a character, it logs an error.
 
+### [YAML linter](hooks/yaml_linter.py)
+
+This hook runs [yamllint](https://yamllint.readthedocs.io/) over the yaml files
+in a recipe before exporting them (it runs in the `pre_export` hook), it can be
+really useful to check for typos.
+
+This hook requires additional dependencies to work: `pip install yamllint`.
+
 ## License
 
 [MIT License](LICENSE)

hooks/yaml_linter.py

@@ -0,0 +1,63 @@
+# coding=utf-8
+
+import os
+import platform
+import subprocess
+
+from conans.errors import ConanException
+from conans.tools import logger
+
+
+CONAN_HOOK_YAMLLINT_WERR = "CONAN_YAMLLINT_WERR"
+
+
+def pre_export(output, conanfile_path, *args, **kwargs):
+    try:
+        import yamllint
+    except ImportError as e:
+        output.error("Install yamllint to use 'yaml_linter' hook: 'pip install yamllint'")
+        return
+    output.info("Lint yaml '{}'".format(conanfile_path))
+    conanfile_dirname = os.path.dirname(conanfile_path)
+
+    rules = {
+        "document-start": "disable",
+        "line-length": "disable",
+        "new-lines": "{level: warning}",
+        "empty-lines": "{level: warning}",
+        "indentation": "{level: warning}",
+        "trailing-spaces": "{level: warning}",
+    }
+
+    lint_args = ['-f', 'parsable',
+                 '-d', '"{extends: default, rules: {%s}}"' %
+                 ", ".join("%s: %s" % (r, rules[r]) for r in rules)]
+    lint_args.append('"%s"' % conanfile_dirname.replace('\\', '/'))
+    configfile = os.path.join(conanfile_dirname, "..", "config.yml")
+    if os.path.isfile(configfile):
+        lint_args.append('"%s"' % configfile.replace('\\', '/'))
+
+    try:
+        command = ['yamllint'] + lint_args
+        command = " ".join(command)
+        shell = bool(platform.system() != "Windows")
+        p = subprocess.Popen(command, shell=shell, bufsize=10,
+                             stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        yamllint_stdout, yamllint_stderr = p.communicate()
+        yamllint_stdout = yamllint_stdout.decode('utf-8')
+    except Exception as exc:
+        output.error("Unexpected error running linter: {}".format(exc))
+        return
+    errors = 0
+    for line in yamllint_stdout.splitlines():
+        output.info(line)
+        i = line.find(":")
+        line = line[i:]
+        i = line.find(":")
+        line = line[i:]
+        parts = line.split(' ')
+        errors += int(parts[1] == "[error]")
+
+    output.info("YAML Linter detected '{}' errors".format(errors))
+    if os.getenv(CONAN_HOOK_YAMLLINT_WERR) and errors:
+        raise ConanException("Package recipe has YAML linter errors. Please fix them.")

tests/requirements_test.txt

@@ -4,4 +4,5 @@ responses
 pluggy==0.11.0
 pylint==2.10.2
 astroid
-spdx_lookup
+spdx_lookup
+yamllint

tests/test_hooks/test_yaml_linter.py

@@ -0,0 +1,74 @@
+# coding=utf-8
+
+import os
+import textwrap
+import unittest
+
+from parameterized import parameterized
+
+from conans import tools
+from conans.client.command import ERROR_GENERAL, SUCCESS
+from conans.tools import environment_append
+from tests.utils.test_cases.conan_client import ConanClientTestCase
+
+
+class YAMLLinterTests(ConanClientTestCase):
+    conanfile = textwrap.dedent(r"""
+        from conans import ConanFile, tools
+
+        class TestConan(ConanFile):
+            name = "name"
+            version = "version"
+        """)
+
+    def _get_environ(self, **kwargs):
+        kwargs = super(YAMLLinterTests, self)._get_environ(**kwargs)
+        kwargs.update({'CONAN_HOOKS': os.path.join(os.path.dirname(
+            __file__), '..', '..', 'hooks', 'yaml_linter')})
+        return kwargs
+
+    @parameterized.expand([(False, ), (True, )])
+    def test_basic(self, yamllint_werr):
+        conandatafile = textwrap.dedent(r"""
+            sources:
+            "version":
+                url: "https://url.to/name/version.tar.xz"
+                sha256: "3a530d1b243b5dec00bc54937455471aaa3e56849d2593edb8ded07228202240"
+            patches:
+            "version":
+                - patch_file: "patches/abcdef.diff"
+                  base_path: "source"
+            patches:
+            """)
+        tools.save('conanfile.py', content=self.conanfile)
+        tools.save('conandata.yml', content=conandatafile)
+        yamllint_werr_value = "1" if yamllint_werr else None
+        with environment_append({"CONAN_YAMLLINT_WERR": yamllint_werr_value}):
+            return_code = ERROR_GENERAL if yamllint_werr else SUCCESS
+            output = self.conan(['export', '.', 'name/version@'], expected_return_code=return_code)
+
+            if yamllint_werr:
+                self.assertIn("pre_export(): Package recipe has YAML linter errors."
+                              " Please fix them.", output)
+
+            self.assertIn("conandata.yml:10:1:"
+                          " [error] duplication of key \"patches\" in mapping (key-duplicates)",
+                            output)
+
+    def test_path_with_spaces(self):
+        conandatafile = textwrap.dedent(r"""
+            sources:
+            "version":
+                url: "https://url.to/name/version.tar.xz"
+                sha256: "3a530d1b243b5dec00bc54937455471aaa3e56849d2593edb8ded07228202240"
+            patches:
+            "version":
+                - patch_file: "patches/abcdef.diff"
+                  base_path: "source"
+            """)
+        tools.save(os.path.join("path spaces", "conanfile.py"), content=self.conanfile)
+        tools.save(os.path.join("path spaces", "conandata.py"), content=conandatafile)
+        output = self.conan(['export', 'path spaces/conanfile.py', 'name/version@'])
+        recipe_path = os.path.join(os.getcwd(), "path spaces", "conanfile.py")
+        self.assertIn("pre_export(): Lint yaml '{}'".format(recipe_path), output)
+        self.assertIn("pre_export(): YAML Linter detected '0' errors", output)