skip_rows for Excel_Workbook.read. (#11560)

- Adds `skip_rows` to `Excel_Workbook.read`.
- Support for read by index.

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

@@ -18,7 +18,7 @@ excel_2007_row_limit = 1048576
 type Excel_Range
     ## PRIVATE
        Specifies a range within an Excel Workbook.
-    Value java_range:Java_Range
+    private Value java_range:Java_Range
 
     ## GROUP Standard.Base.Metadata
        ICON metadata

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

@@ -221,16 +221,20 @@ type Excel_Workbook
          `Detect_Headers`).
        - limit: the maximum number of rows to read.
          If set to `Nothing`, all rows will be returned.
-    @query (self-> Single_Choice display=Display.Always values=(self.tables.at "Name" . to_vector . map t-> Option t t.pretty))
+    @query self-> _query_widget self
     @limit Rows_To_Read.default_widget
-    read : Text | Excel_Range -> Headers -> Rows_To_Read -> Problem_Behavior -> Table
-    read self (query : Text | Excel_Range) (headers : Headers = Headers.Detect_Headers) (limit : Rows_To_Read = ..All_Rows) (on_problems:Problem_Behavior=..Report_Warning) =
+    read : Text | Excel_Range | Integer -> Headers -> Rows_To_Read -> Integer -> Problem_Behavior -> Table
+    read self (query : Text | Excel_Range | Integer) (headers : Headers = ..Detect_Headers) (limit : Rows_To_Read = ..All_Rows) (skip_rows:Integer=0) (on_problems:Problem_Behavior=..Report_Warning) =
         java_headers = Excel_Reader.make_java_headers headers
         java_limit = limit.rows_to_read
         java_table = Java_Problems.with_problem_aggregator on_problems java_problem_aggregator->
             self.with_java_workbook java_workbook-> case query of
-                _ : Excel_Range -> ExcelReader.readRange java_workbook query.java_range java_headers 0 java_limit java_problem_aggregator
-                _ : Text -> ExcelReader.readRangeByName java_workbook query java_headers 0 java_limit java_problem_aggregator
+                _ : Excel_Range -> ExcelReader.readRange java_workbook query.java_range java_headers skip_rows java_limit java_problem_aggregator
+                _ : Text -> ExcelReader.readRangeByName java_workbook query java_headers skip_rows java_limit java_problem_aggregator
+                _ : Integer ->
+                    names = self.sheet_names
+                    if (query < 1 || query >= names.length) then Error.throw (Illegal_Argument.Error "Worksheet index out of range (1 - "+names.length.to_text+").") else
+                        ExcelReader.readRangeByName java_workbook (names.at (query - 1)) java_headers skip_rows java_limit java_problem_aggregator
         limit.attach_warning (Table.Value java_table)
 
     ## PRIVATE
@@ -378,3 +382,10 @@ type Return_As
 
     ## All sheets are merged into a single table. A union operation is performed.
     Merged_Table (columns_to_keep : Columns_To_Keep = Columns_To_Keep.In_Any) (match : Match_Columns = Match_Columns.By_Name)
+
+## PRIVATE
+   Creates a query widget for the `read` method.
+private _query_widget wb:Excel_Workbook display:Display=..Always -> Widget =
+    default_address = "'" + wb.sheet_names.first.replace "'" "''" + "'!A1:E5"
+    options = [Option "<By Index>" "1", Option "<Range>" "Excel_Range.from_address "+default_address.pretty] + (wb.tables.at "Name" . to_vector . map t-> Option t t.pretty)
+    Single_Choice display=display values=options

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

@@ -131,8 +131,8 @@ prepare_file_modification_strategy table section on_existing_file match_columns
             java_headers = Excel_Reader.make_java_headers headers
             java_limit = row_limit.rows_to_write
             java_range = case address of
-                Excel_Range.Value java_range -> java_range
-                text : Text -> text
+                _ : Excel_Range -> address.java_range
+                _ : Text -> address
             workbook_to_modify->
                 ExcelWriter.writeTableToRange workbook_to_modify java_range existing_data_mode skip_rows table.java_table java_limit java_headers
 

std-bits/table/src/main/java/org/enso/table/read/ExcelReader.java

@@ -279,7 +279,7 @@ private static <T> T withWorkbook(File file, ExcelFileFormat format, Function<Wo
     }
   }
 
-  private static Table readRange(
+  public static Table readRange(
       Workbook workbook,
       ExcelRange excelRange,
       ExcelHeaders.HeaderBehavior headers,

test/Table_Tests/src/IO/Excel_Spec.enso

@@ -58,6 +58,32 @@ spec_fmt suite_builder header file read_method sheet_count=5 =
             t.columns.map .name . should_equal ['Item', 'Price', 'Quantity', 'Price 1']
             t.at 'Price 1' . to_vector . should_equal [20, 40, 0, 60, 0, 10]
 
+        group_builder.specify "should allow reading with limited rows and skipping rows from workbook" <|
+            wb = read_method file
+            t = wb.read 1 headers=..No_Headers
+            t.column_names.should_equal ['A', 'B', 'C']
+
+            t_1 = wb.read 1 headers=..No_Headers limit=3
+            t_1.column_names . should_equal t.column_names
+            t_1.row_count . should_equal 3
+            t_1.at 'A' . to_vector . should_equal  ['Name', 'blouse', 't-shirt']
+            t_1.at 'B' . to_vector . should_equal  ['Quantity', 10, 20]
+            t_1.at 'C' . to_vector . should_equal  ['Price', 22.3, 32]
+
+            t_2 = wb.read 1 headers=..No_Headers skip_rows=3
+            t_2.column_names . should_equal t.column_names
+            t_2.row_count . should_equal 4
+            t_2.at 'A' . to_vector . should_equal ['trousers', 'shoes', 'skirt', 'dress']
+            t_2.at 'B' . to_vector . should_equal [Nothing, 30, Nothing, 5]
+            t_2.at 'C' . to_vector . should_equal [43.2, 54, 31, Nothing]
+
+            t_3 = wb.read 1 headers=..No_Headers limit=2 skip_rows=3
+            t_3.column_names . should_equal t.column_names
+            t_3.row_count . should_equal 2
+            t_3.at 'A' . to_vector . should_equal ['trousers', 'shoes']
+            t_3.at 'B' . to_vector . should_equal [Nothing, 30]
+            t_3.at 'C' . to_vector . should_equal [43.2, 54]
+
         group_builder.specify "should allow reading with cell range specified" <|
             t_1 = read_method file (..Range "Simple!B:C")
             t_1.columns.map .name . should_equal ['Quantity', 'Price']