Allow EXTENDS recursively (#2322)

* Allow EXTENDS recursively

* [MegaLinter] Apply linters fixes

---------

Co-authored-by: bdovaz <[email protected]>

Author: bdovaz

.automation/test/mega-linter-config-test/recurse.mega-linter.yml

@@ -0,0 +1,3 @@
+EXTENDS: local.mega-linter.yml
+DEFAULT_BRANCH: dev
+LOG_LEVEL: DEBUG

megalinter/config.py

@@ -72,30 +72,45 @@ def init_config(workspace=None):
     # manage EXTENDS in configuration
     if "EXTENDS" in runtime_config:
         combined_config = {}
-        extends = runtime_config["EXTENDS"]
-        if isinstance(extends, str):
-            extends = extends.split(",")
-        for extends_item in extends:
-            if extends_item.startswith("http"):
-                r = requests.get(extends_item, allow_redirects=True)
-                assert (
-                    r.status_code == 200
-                ), f"Unable to retrieve EXTENDS config file {config_file_name}"
-                extends_config_data = yaml.safe_load(r.content)
-            else:
-                with open(
-                    workspace + os.path.sep + extends_item, "r", encoding="utf-8"
-                ) as f:
-                    extends_config_data = yaml.safe_load(f)
-            combined_config.update(extends_config_data)
-            CONFIG_SOURCE += f"\n[config] - extends from: {extends_item}"
-        combined_config.update(runtime_config)
+        CONFIG_SOURCE = combine_config(
+            workspace, config_file_name, runtime_config, combined_config, CONFIG_SOURCE
+        )
         runtime_config = combined_config
     # Print & set config in cache
     print(f"[config] {CONFIG_SOURCE}")
     set_config(runtime_config)
 
 
+def combine_config(workspace, config_file_name, config, combined_config, config_source):
+    extends = config["EXTENDS"]
+    if isinstance(extends, str):
+        extends = extends.split(",")
+    for extends_item in extends:
+        if extends_item.startswith("http"):
+            r = requests.get(extends_item, allow_redirects=True)
+            assert (
+                r.status_code == 200
+            ), f"Unable to retrieve EXTENDS config file {config_file_name}"
+            extends_config_data = yaml.safe_load(r.content)
+        else:
+            with open(
+                workspace + os.path.sep + extends_item, "r", encoding="utf-8"
+            ) as f:
+                extends_config_data = yaml.safe_load(f)
+        combined_config.update(extends_config_data)
+        config_source += f"\n[config] - extends from: {extends_item}"
+        if "EXTENDS" in extends_config_data:
+            combine_config(
+                workspace,
+                extends_item,
+                extends_config_data,
+                combined_config,
+                config_source,
+            )
+    combined_config.update(config)
+    return config_source
+
+
 def get_config():
     global CONFIG_DATA
     if CONFIG_DATA is not None:

megalinter/tests/test_megalinter/config_test.py

@@ -61,6 +61,23 @@ def test_local_config_extends_success(self):
         self.assertEqual("(local)", config.get("FILTER_REGEX_INCLUDE"))
         self.assertEqual("false", config.get("SHOW_ELAPSED_TIME"))
 
+    def test_local_config_extends_recurse_success(self):
+        local_config = "recurse.mega-linter.yml"
+        os.environ["MEGALINTER_CONFIG"] = local_config
+        config.init_config(
+            REPO_HOME_DEFAULT
+            + os.path.sep
+            + ".automation"
+            + os.path.sep
+            + "test"
+            + os.path.sep
+            + "mega-linter-config-test"
+        )
+        self.assertEqual("(local)", config.get("FILTER_REGEX_INCLUDE"))
+        self.assertEqual("false", config.get("SHOW_ELAPSED_TIME"))
+        self.assertEqual("dev", config.get("DEFAULT_BRANCH"))
+        self.assertEqual("DEBUG", config.get("LOG_LEVEL"))
+
     def test_local_config_extends_error(self):
         local_config = "local-error.mega-linter.yml"
         os.environ["MEGALINTER_CONFIG"] = local_config