Add function data.util.get_unique_names_domain

Orange/data/tests/test_util.py

@@ -1,7 +1,8 @@
 import unittest
 
 from Orange.data import Domain, ContinuousVariable
-from Orange.data.util import get_unique_names, get_unique_names_duplicates
+from Orange.data.util import \
+    get_unique_names, get_unique_names_duplicates, get_unique_names_domain
 
 
 class TestGetUniqueNames(unittest.TestCase):
@@ -63,6 +64,56 @@ def test_get_unique_names_from_duplicates(self):
             get_unique_names_duplicates(["x", "", "", None, None, "x"]),
             ["x (1)", "", "", None, None, "x (2)"])
 
+    def test_get_unique_names_domain(self):
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain(["a", "t", "c", "t"], ["t", "d"], ["d", "e"])
+        self.assertEqual(attrs, ["a", "t (1)", "c", "t (2)"])
+        self.assertEqual(classes, ["t (3)", "d (1)"])
+        self.assertEqual(metas, ["d (2)", "e"])
+        self.assertEqual(renamed, ["t", "d"])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain(["a", "t", "c", "t"], ["t", "d"])
+        self.assertEqual(attrs, ["a", "t (1)", "c", "t (2)"])
+        self.assertEqual(classes, ["t (3)", "d"])
+        self.assertEqual(metas, [])
+        self.assertEqual(renamed, ["t"])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain(["a", "t", "c"])
+        self.assertEqual(attrs, ["a", "t", "c"])
+        self.assertEqual(classes, [])
+        self.assertEqual(metas, [])
+        self.assertEqual(renamed, [])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain(["a", "t", "d", "t"], [], ["d", "e"])
+        self.assertEqual(attrs, ["a", "t (1)", "d (1)", "t (2)"])
+        self.assertEqual(classes, [])
+        self.assertEqual(metas, ["d (2)", "e"])
+        self.assertEqual(renamed, ["t", "d"])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain([], ["t", "d"], ["d", "e"])
+        self.assertEqual(attrs, [])
+        self.assertEqual(classes, ["t", "d (1)"])
+        self.assertEqual(metas, ["d (2)", "e"])
+        self.assertEqual(renamed, ["d"])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain([], ["t", "t", "d"], [])
+        self.assertEqual(attrs, [])
+        self.assertEqual(classes, ["t (1)", "t (2)", "d"])
+        self.assertEqual(metas, [])
+        self.assertEqual(renamed, ["t"])
+
+        (attrs, classes, metas), renamed = \
+            get_unique_names_domain([], [], [])
+        self.assertEqual(attrs, [])
+        self.assertEqual(classes, [])
+        self.assertEqual(metas, [])
+        self.assertEqual(renamed, [])
+
 
 if __name__ == "__main__":
     unittest.main()

Orange/data/util.py

@@ -221,3 +221,32 @@ def get_unique_names_duplicates(proposed: list) -> list:
             name = unique_name
         names.append(name)
     return names
+
+
+def get_unique_names_domain(attributes, class_vars=(), metas=()):
+    """
+    Return de-duplicated names for variables for attributes, class_vars
+    and metas. If a name appears more than once, the function appends
+    indices in parentheses.
+
+    Args:
+        attributes (list of str): proposed names for attributes
+        class_vars (list of str): proposed names for class_vars
+        metas (list of str): proposed names for metas
+
+    Returns:
+        (attributes, class_vars, metas): new names
+        renamed: list of names renamed variables; names appear in order of
+            appearance in original lists; every name appears only once
+    """
+    all_names = list(chain(attributes, class_vars, metas))
+    unique_names = get_unique_names_duplicates(all_names)
+    # don't be smart with negative indices: they won't work for empty lists
+    attributes = unique_names[:len(attributes)]
+    class_vars = unique_names[len(attributes):len(attributes) + len(class_vars)]
+    metas = unique_names[len(attributes) + len(class_vars):]
+    # use dict, not set, to keep the order
+    renamed = list(dict.fromkeys(old
+                                 for old, new in zip(all_names, unique_names)
+                                 if new != old))
+    return (attributes, class_vars, metas), renamed