Custom methods must be protected

hooks/conan-center.py

@@ -7,8 +7,9 @@
 import sys
 from logging import WARNING, ERROR, INFO, DEBUG, NOTSET
 
+
+from conans import tools, ConanFile
 import yaml
-from conans import tools
 try:
     from conans import Settings
 except ImportError:
@@ -46,6 +47,7 @@
              "KB-H031": "CONANDATA.YML REDUCE",
              "KB-H032": "SYSTEM REQUIREMENTS",
              "KB-H034": "TEST PACKAGE - NO IMPORTS()",
+             "KB-H036": "CUSTOM METHODS",             
              "KB-H037": "NO AUTHOR",
              "KB-H040": "NO TARGET NAME",
              "KB-H041": "NO FINAL ENDLINE",
@@ -421,6 +423,31 @@ def test(out):
         if "def imports" in test_package_conanfile:
             out.error("The method `imports` is not allowed in test_package/conanfile.py")
 
+    @run_test("KB-H036", output)
+    def test(out):
+        def get_methods(conanfile):
+            methods = []
+            for member in dir(conanfile):
+
+                try:
+                    if callable(getattr(conanfile, member)):
+                        methods.append(str(member))
+                except:
+                    methods.append(str(member))
+            return methods
+
+        mock = ConanFile(conanfile.output, None)
+        valid_attrs = get_methods(mock)
+        current_attrs = get_methods(conanfile)
+        invalid_attrs = re.findall(r"def (__.*[^_])\s?\(", conanfile_content, re.MULTILINE)
+        for attr in current_attrs:
+            if not attr.startswith("_") and attr not in valid_attrs:
+                invalid_attrs.append(attr)
+
+        if invalid_attrs:
+            out.error("Custom methods must be declared as protected. " \
+                      "The follow methods are invalid: '{}'".format("', '".join(invalid_attrs)))
+
     @run_test("KB-H037", output)
     def test(out):
         author = getattr(conanfile, "author", None)

tests/test_hooks/conan-center/test_conan-center.py

@@ -118,6 +118,7 @@ def test_conanfile(self):
         self.assertIn("ERROR: [CONAN CENTER INDEX URL (KB-H027)] The attribute 'url' should " \
                       "point to: https://github.com/conan-io/conan-center-index", output)
         self.assertIn("[CMAKE MINIMUM VERSION (KB-H028)] OK", output)
+        self.assertIn("[CUSTOM METHODS (KB-H036)] OK", output)
         self.assertIn("[SYSTEM REQUIREMENTS (KB-H032)] OK", output)
         self.assertIn("[SINGLE REQUIRES (KB-H055)] OK", output)
 
@@ -141,6 +142,7 @@ def test_conanfile_header_only(self):
                       "recipe", output)
         self.assertIn("[META LINES (KB-H025)] OK", output)
         self.assertIn("[CMAKE MINIMUM VERSION (KB-H028)] OK", output)
+        self.assertIn("[CUSTOM METHODS (KB-H036)] OK", output)
         self.assertIn("[SYSTEM REQUIREMENTS (KB-H032)] OK", output)
 
     def test_conanfile_header_only_with_settings(self):
@@ -162,6 +164,7 @@ def test_conanfile_header_only_with_settings(self):
                       "recipe", output)
         self.assertIn("[META LINES (KB-H025)] OK", output)
         self.assertIn("[CMAKE MINIMUM VERSION (KB-H028)] OK", output)
+        self.assertIn("[CUSTOM METHODS (KB-H036)] OK", output)
         self.assertIn("[SYSTEM REQUIREMENTS (KB-H032)] OK", output)
 
     def test_conanfile_settings_clear_with_settings(self):
@@ -204,6 +207,7 @@ def test_conanfile_installer(self):
                       "recipe", output)
         self.assertIn("[META LINES (KB-H025)] OK", output)
         self.assertIn("[CMAKE MINIMUM VERSION (KB-H028)] OK", output)
+        self.assertIn("[CUSTOM METHODS (KB-H036)] OK", output)
 
     def test_shebang(self):
         conanfile = textwrap.dedent("""\
@@ -604,6 +608,41 @@ def system_requirements(self):
         self.assertIn("[SYSTEM REQUIREMENTS (KB-H032)] 'libusb' is part of the allowlist.", output)
         self.assertNotIn("ERROR: [SYSTEM REQUIREMENTS (KB-H032)]", output)
 
+    def test_invalid_recipe_methods(self):
+        conanfile = textwrap.dedent("""\
+        from conans import ConanFile
+        class AConan(ConanFile):
+            url = "fake_url.com"
+            license = "fake_license"
+            description = "whatever"
+            homepage = "homepage.com"
+            topics = ("fake_topic", "another_fake_topic")
+
+            def configure(self):
+                self.output.info("ok")
+
+            def barbarian(self):
+                self.output.info("Conan")
+
+            def __my_own_method(self):
+                self.output.info("foobar")
+
+            def __my_private_method(self):
+                self.output.info("foobar")
+
+            def __abs__(self):
+                return self.version
+
+            def _baz(self):
+                self.output.info("qux")
+
+        """)
+        tools.save('conanfile.py', content=conanfile)
+        output = self.conan(['create', '.', 'name/version@user/test'])
+        self.assertIn("ERROR: [CUSTOM METHODS (KB-H036)] Custom methods must be declared as "
+                      "protected. The follow methods are invalid: '__my_own_method', "
+                      "'__my_private_method', 'barbarian'", output)
+
     def test_imports_not_allowed(self):
         conanfile_tp = textwrap.dedent("""\
         from conans import ConanFile, tools