ARROW-8369: [CI] Fix crossbow wildcard groups

Closes #6868 from nealrichardson/fix-r-crossbow-group

Lead-authored-by: Neal Richardson <neal.p.richardson@gmail.com>
Co-authored-by: Krisztián Szűcs <szucs.krisztian@gmail.com>
Signed-off-by: Krisztián Szűcs <szucs.krisztian@gmail.com>

dev/tasks/crossbow.py

@@ -1094,14 +1094,15 @@ def select(self, tasks=None, groups=None):
 
     def validate(self):
         # validate that the task groups are properly referening the tasks
-        for group in self['groups']:
-            tasks = self.select(groups=[group])
-            if not tasks:
-                raise ValueError(
-                    "The patterns defined for task group `{}` are not "
-                    "matching any of the tasks defined in the configuration "
-                    "file.".format(group)
-                )
+        for group_name, group in self['groups'].items():
+            for pattern in group:
+                tasks = self.select(tasks=[pattern])
+                if not tasks:
+                    raise ValueError(
+                        "The pattern `{}` defined for task group `{}` is not "
+                        "matching any of the tasks defined in the "
+                        "configuration file.".format(pattern, group_name)
+                    )
 
         # validate that the tasks are constructible
         for task_name, task in self['tasks'].items():

dev/tasks/tasks.yml

@@ -58,7 +58,8 @@ groups:
     - test-*python*
 
   r:
-    - test-*r*
+    - test*-r-*
+    - homebrew-r-autobrew
 
   ruby:
     - test-*ruby*