Add tests for Table.get_row and fix a bug (#13795)

Fixes #12317

Adds tests for get_row and fixes get_row -1 out of bounds for In_DB

Author: AdRiley

distribution/lib/Standard/Database/0.0.0-dev/src/Internal/DB_Table_Implementation.enso

@@ -113,10 +113,9 @@ type DB_Table_Implementation
 
     get_row (this_table : Table & DB_Table) index:Integer ~if_missing:Any =
         Feature.Sample.if_supported_else_throw this_table.connection.dialect "get_row" <|
-            if index == -1 then this_table.last_row else
-                real_row = (if index < 0 then index + this_table.row_count else index)
-                if real_row < 0 then if_missing else
-                    this_table.rows real_row+1 . get real_row if_missing
+            real_row = (if index < 0 then index + this_table.row_count else index)
+            if real_row < 0 then if_missing else
+                this_table.rows real_row+1 . get real_row if_missing
 
     first_value (this_table : Table & DB_Table) =
         Feature.Column_Operations.if_supported_else_throw this_table.connection.dialect "first_value" <|

distribution/lib/Standard/Table/0.0.0-dev/docs/api/Table.md

@@ -37,7 +37,7 @@
     - from_union tables:(Standard.Base.Data.Vector.Vector Standard.Table.Table.Table) columns_to_keep:Standard.Table.Columns_To_Keep.Columns_To_Keep= match_columns:Standard.Table.Match_Columns.Match_Columns= on_problems:Standard.Base.Errors.Problem_Behavior.Problem_Behavior= -> (Standard.Table.Table.Table&Standard.Table.In_Memory_Table.In_Memory_Table&Standard.Base.Any.Any)!(Standard.Table.Errors.No_Output_Columns|Standard.Base.Errors.Illegal_Argument.Illegal_Argument)
     - generate_rows self over:Standard.Table.Generate_Rows_Range.Generate_Rows_Range= as:Standard.Base.Data.Text.Text= on_problems:Standard.Base.Errors.Problem_Behavior.Problem_Behavior= -> Standard.Base.Any.Any
     - get self selector:(Standard.Base.Data.Numbers.Integer|Standard.Base.Data.Text.Text)= ~if_missing:Standard.Base.Any.Any= -> (Standard.Table.Column.Column|Standard.Base.Any.Any)
-    - get_row self index:Standard.Base.Data.Numbers.Integer= ~if_missing:Standard.Base.Any.Any= -> Standard.Table.Row.Row
+    - get_row self index:Standard.Base.Data.Numbers.Integer= ~if_missing:Standard.Base.Any.Any= -> (Standard.Table.Row.Row|Standard.Base.Any.Any)
     - get_value self selector:(Standard.Base.Data.Text.Text|Standard.Base.Data.Numbers.Integer)= index:Standard.Base.Data.Numbers.Integer= ~if_missing:Standard.Base.Any.Any= -> Standard.Base.Any.Any
     - input columns:(Standard.Base.Data.Vector.Vector Standard.Base.Any.Any) -> (Standard.Table.Table.Table&Standard.Table.In_Memory_Table.In_Memory_Table&Standard.Base.Any.Any)
     - join self right:Standard.Table.Table.Table= join_kind:Standard.Table.Join_Kind.Join_Kind= on:(Standard.Base.Any.Any|Standard.Base.Data.Text.Text|Standard.Table.Join_Condition.Join_Condition)= right_prefix:Standard.Base.Data.Text.Text= on_problems:Standard.Base.Errors.Problem_Behavior.Problem_Behavior= -> (Standard.Table.Table.Table&Standard.Base.Any.Any)

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

@@ -463,7 +463,7 @@ type Table
         - `index`: The index of the row to get within the table.
         - `if_missing`: The value to use if the selector isn't present.
     @index (t-> Widget.Numeric_Input minimum=0 maximum=t.row_count-1)
-    get_row self index:Integer=0 ~if_missing:Any=Nothing -> Row =
+    get_row self index:Integer=0 ~if_missing:Any=Nothing -> Row | Any =
         self.implementation.get_row self.underlying index if_missing
 
     ## ---

test/Table_Tests/src/Common_Table_Operations/Core_Spec.enso

@@ -261,6 +261,38 @@ add_core_specs suite_builder setup =
             last_row.at "Y" . should_equal 8
             last_row.at "Z" . should_equal "D"
 
+        group_builder.specify "should let you get an indexed row using get_row" <|
+            row = data.table.get_row 0
+            row . length . should_equal 3
+            row.at "X" . should_equal 1
+            row.at "Y" . should_equal 5
+            row.at "Z" . should_equal "A"
+
+        group_builder.specify "calling get_row with negative indexes, indexes from right" <|
+            last_row = data.table.get_row -1
+            last_row . length . should_equal 3
+            last_row.at "X" . should_equal 4
+            last_row.at "Y" . should_equal 8
+            last_row.at "Z" . should_equal "D"
+            first_row = data.table.get_row -4
+            first_row . length . should_equal 3
+            first_row.at "X" . should_equal 1
+            first_row.at "Y" . should_equal 5
+            first_row.at "Z" . should_equal "A"
+
+        group_builder.specify "calling get_row with out of bounds should return if_missing" <|
+            out_of_bounds_top_row = data.table.get_row 4 Nothing
+            out_of_bounds_top_row . should_equal Nothing
+            out_of_bounds_bottom_row = data.table.get_row -5 Nothing
+            out_of_bounds_bottom_row . should_equal Nothing
+
+        group_builder.specify "empty table get_row should return if_missing" <|
+            empty_table = data.table.take 0
+            empty_table.get_row -2 . should_equal Nothing
+            empty_table.get_row -1 . should_equal Nothing
+            empty_table.get_row 0 . should_equal Nothing
+            empty_table.get_row 1 . should_equal Nothing
+
         group_builder.specify "should fetch rows up to the specified limit" <|
             data.table.rows max_rows=2 . map .to_vector . should_equal [[1, 5, "A"], [2, 6, "B"]]