tokenize_to_columns or parse_to_columns results in a single column we shouldn't add the 1

distribution/lib/Standard/Table/0.0.0-dev/src/Internal/Split_Tokenize.enso

@@ -123,7 +123,7 @@ fan_out_to_columns table input_column_id function column_count=Nothing on_proble
     input_column = table.get input_column_id
     problem_builder = Problem_Builder.new
     new_columns_unrenamed = map_columns_to_multiple input_column function column_count problem_builder
-    new_columns = rename_new_columns table new_columns_unrenamed problem_builder
+    new_columns = rename_new_columns table input_column.name new_columns_unrenamed problem_builder
     new_table = replace_column_with_columns table input_column new_columns
     problem_builder.attach_problems_after on_problems new_table
 
@@ -315,17 +315,22 @@ map_columns_to_multiple input_column function column_count problem_builder =
 
             builders
 
+    # Name columns. If there's only one, use the original column name.
+    new_column_names = case builders.length of
+        1 -> [input_column.name]
+        _ -> 0.up_to builders.length . map i-> default_column_namer input_column.name i
+
     # Build Columns.
-    builders.map .seal . map_with_index i-> storage->
-        name = default_column_namer input_column.name i
-        Column.from_storage name storage
+    sealed = builders.map .seal
+    new_column_names.zip sealed Column.from_storage
 
 ## PRIVATE
    Rename a vector of columns to be unique when added to a table.
-rename_new_columns : Table -> Vector Column -> Problem_Builder -> Vector Column
-rename_new_columns table columns problem_builder =
+rename_new_columns : Table -> Text -> Vector Column -> Problem_Builder -> Vector Column
+rename_new_columns table removed_column_name columns problem_builder =
     unique = Unique_Name_Strategy.new
-    unique.mark_used <| table.columns.map .name
+    remaining_columns = table.columns . filter (c-> c.name != removed_column_name) . map .name
+    unique.mark_used remaining_columns
     new_columns = columns.map column->
         new_name = unique.make_unique column.name
         column.rename new_name

test/Table_Tests/src/In_Memory/Split_Tokenize_Spec.enso

@@ -42,6 +42,14 @@ spec =
             t2 = t.split_to_rows "bar" "b"
             t2.should_equal expected
 
+        Test.specify "can do split_to_columns with one output column, no column suffix added" <|
+            cols = [["foo", [0, 1, 2]], ["bar", ["abc", "cbdbef", "ghbijbu"]]]
+            t = Table.new cols
+            expected_rows = [[0, "abc"], [1, "cbdbef"], [2, "ghbijbu"]]
+            expected = Table.from_rows ["foo", "bar"] expected_rows
+            t2 = t.split_to_columns "bar" "q"
+            t2.should_equal expected
+
     Test.group "Table.tokenize" <|
         Test.specify "can do tokenize_to_columns" <|
             cols = [["foo", [0, 1, 2]], ["bar", ["a12b34r5", "23", "2r4r55"]]]
@@ -75,6 +83,14 @@ spec =
             t2 = t.tokenize_to_rows "bar" "\d+"
             t2.should_equal expected
 
+        Test.specify "can do tokenize_to_columns with one output column, no column suffix needed" <|
+            cols = [["foo", [0, 1, 2]], ["bar", ["a12b", "23", "2r"]]]
+            t = Table.new cols
+            expected_rows = [[0, "12"], [1, "23"], [2, "2"]]
+            expected = Table.from_rows ["foo", "bar"] expected_rows
+            t2 = t.tokenize_to_columns "bar" "\d+"
+            t2.should_equal expected
+
         Test.specify "can do tokenize_to_rows with some rows that have no matches" <|
             cols = [["foo", [0, 1, 2, 3]], ["bar", ["a12b34r5", "23", "q", "2r4r55"]]]
             t = Table.new cols