Version 0.4.0

### Added
- Method Sheet#last_column().
- Method Sheet#empty?().
- Several test assertions for new functionality.
- Using new xlsx_drone version (0.2.0).

.gitignore

@@ -1,10 +1,10 @@
 .idea/
-Gemfile.lock
-ProgrammerNotes.md
-*.gem
+.yardoc/
+coverage/
+doc/
 releases/
 test/benchmark/*.xlsx
 !test/benchmark/xlsx_200000_rows.xlsx
-.yardoc/
-coverage/
-doc/
+Gemfile.lock
+ProgrammerNotes.md
+*.gem

CHANGELOG.md

@@ -6,6 +6,13 @@ Removed, Fixed, Security, and others; and this project adheres to [Semantic Vers
 
 ## [Unreleased]
 
+## [0.4.0] - 2021-01-16
+### Added
+- Method Sheet#last_column().
+- Method Sheet#empty?().
+- Several test assertions for new functionality.
+- Using new xlsx_drone version (0.2.0).
+
 ## [0.3.0] - 2021-01-12
 ### Added
 - A benchmark comparison against other xlsx reading libraries.

README.md

@@ -13,6 +13,7 @@ Fast _Microsoft Excel's_ **\*.xlsx** reader. Binding of [C's xlsx_drone](https:/
 * [Usage](#usage)
 * [API](#api)  
 * [TODO](#todo)
+* [News](#news)  
 * [License](#license)
 
 ## Summary
@@ -47,8 +48,9 @@ sheet = wb.load_sheet(1) #: XLSXDrone::Sheet
 puts "Sheet #1 name: #{sheet.name}"
 
 1.upto(sheet.last_row) do |row|
-  p sheet.read_cell(row, 'A')
-  p sheet.read_cell(row, 'B')
+  'A'.upto(sheet.last_column) do |column|
+    p sheet.read_cell(row, column)
+  end
 end
 ```
 
@@ -67,6 +69,12 @@ Also, consider that this TODO list is somehow concatenated to the [C's xlsx_dron
 
 **Be free to [make (or upvote)](https://github.com/damian-m-g/xlsx_drone_rb/issues) any feature request.**
 
+## News
+
+Version 0.4.0 introduces:
+* `Sheet#last_column`
+* `Sheet#empty?`
+
 ## License
 
 #### [MIT](https://github.com/damian-m-g/xlsx_drone_rb/blob/master/LICENSE)

data/shields/assertions.json

@@ -1 +1 @@
-{"schemaVersion":1,"label":"test assertions","message":"112","color":"informational"}
+{"schemaVersion":1,"label":"test assertions","message":"120","color":"informational"}

data/shields/simplecov.json

@@ -1 +1 @@
-{"schemaVersion":1,"label":"coverage","message":"90.15%","color":"brightgreen"}
+{"schemaVersion":1,"label":"coverage","message":"90.84%","color":"brightgreen"}

lib/xlsx_drone/native_binding.rb

@@ -42,6 +42,7 @@ class XLSXSheetT < FFI::Struct
         :sheet_xml, :pointer,
         :sheetdata, :pointer,
         :last_row, :int,
+        :last_column, :pointer,
         :last_row_looked, XLSXReferenceToRowT
     end
 
@@ -70,6 +71,7 @@ class XLSXCellT < FFI::Struct
     attach_function :xlsx_set_print_err_messages, [:int], :void
     attach_function :xlsx_open, [:string, :pointer], :int
     attach_function :xlsx_load_sheet, [:pointer, :int, :string], :pointer
+    attach_function :xlsx_get_last_column, [:pointer], :pointer
     attach_function :xlsx_read_cell, [:pointer, :uint, :string, :pointer], :void
     attach_function :xlsx_close, [:pointer], :int
   end

lib/xlsx_drone/sheet.rb

@@ -3,7 +3,7 @@ module XLSXDrone
 
   # XLSX Sheet.
   class Sheet
-
+    
     # @return [XLSXDrone::Sheet]
     def initialize(xlsx_sheet_mpointer)
       @native_sheet = XLSXDrone::NativeBinding::XLSXSheetT.new(xlsx_sheet_mpointer)
@@ -16,6 +16,26 @@ def last_row
       @native_sheet[:last_row]
     end
 
+    # @return [String] "A" if the sheet is empty
+    def last_column
+      if(!@last_column)
+        mpointer = XLSXDrone::NativeBinding.xlsx_get_last_column(@native_sheet) # NULL or a string
+        if(mpointer.null?)
+          # the sheet is empty
+          @last_column = 'A'
+        else
+          @last_column = mpointer.get_string(0).force_encoding(Encoding::UTF_8)
+        end
+      else
+        @last_column
+      end
+    end
+
+    # @return [Boolean]
+    def empty?
+      last_row() == 0 ? true : false
+    end
+
     # @return [String]
     def name
       @native_sheet[:name].get_string(0).force_encoding(Encoding::UTF_8)

test/tc_sheet.rb

@@ -1,20 +1,58 @@
 class TCSheet < Test::Unit::TestCase
 
-  XLSX_PATH = "#{File.dirname(__FILE__)}/helper/foo.xlsx"
+  TEST_FOLDER_ABSOLUTE_PATH = File.dirname(__FILE__)
+  XLSX_PATH = "#{TEST_FOLDER_ABSOLUTE_PATH}/helper/sample.xlsx"
+  EMPTY_XLSX_PATH = "#{TEST_FOLDER_ABSOLUTE_PATH}/helper/empty_sample.xlsx"
 
   def setup
     @workbook = XLSXDrone.open(XLSX_PATH)
     @sheet = @workbook.load_sheet(1)
   end
 
+  def teardown
+    @workbook.close()
+  end
+
   def test_last_row
     assert_equal(23, @sheet.last_row)
   end
 
+  def test_last_column
+    assert_equal("L", @sheet.last_column)
+    # if called a second time, must return the same
+    assert_equal("L", @sheet.last_column)
+
+    # this sheet has its last column filled in "B", but has styles manually defined at the right
+    sheet = @workbook.load_sheet(2)
+    assert_equal("B", sheet.last_column)
+
+    workbook = XLSXDrone.open(EMPTY_XLSX_PATH)
+    sheet = workbook.load_sheet(1)
+    assert_equal("A", sheet.last_column)
+    # second sheet is also empty but has some styles manually defined
+    sheet = workbook.load_sheet(2)
+    assert_equal("A", sheet.last_column)
+
+    workbook.close()
+  end
+
+  def test_empty?
+    assert_equal(false, @sheet.empty?)
+
+    workbook = XLSXDrone.open(EMPTY_XLSX_PATH)
+    sheet = workbook.load_sheet(1)
+    assert_equal(true, sheet.empty?)
+    # second sheet is also empty but has some styles manually defined
+    sheet = workbook.load_sheet(2)
+    assert_equal(true, sheet.empty?)
+
+    workbook.close()
+  end
+
   def test_name
     assert_equal('Sheet1', @sheet.name)
   end
-
+  
   def test_read_cell
     # headers
     assert_equal("General", @sheet.read_cell(1, "A"))
@@ -144,8 +182,4 @@ def test_read_cell
     assert_equal(nil, @sheet.read_cell(13, "D"))
     assert_equal(nil, @sheet.read_cell(50, "A"))
   end
-
-  def teardown
-    @workbook.close()
-  end
 end

test/tc_workbook.rb

@@ -1,6 +1,6 @@
 class TCWorkbook < Test::Unit::TestCase
 
-  XLSX_PATH = "#{File.dirname(__FILE__)}/helper/foo.xlsx"
+  XLSX_PATH = "#{File.dirname(__FILE__)}/helper/sample.xlsx"
 
   def setup
     @workbook = XLSXDrone.open(XLSX_PATH)

test/tc_xlsx_drone.rb

@@ -1,6 +1,6 @@
 class TCXLSXDrone < Test::Unit::TestCase
 
-  XLSX_PATH = "#{File.dirname(__FILE__)}/helper/foo.xlsx"
+  XLSX_PATH = "#{File.dirname(__FILE__)}/helper/sample.xlsx"
 
   def test_open
     assert_raise(XLSXDrone::LogicError::ClientError::MalformedParams) {XLSXDrone.open(123)}

xlsx_drone.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = "xlsx_drone"
-  s.version = "0.3.0"
+  s.version = "0.4.0"
   s.summary = "Fast Microsoft Excel's XLSX reader. Binding of C's xlsx_drone lib."
   s.author = "Damián M. González"
   s.homepage = "https://github.com/damian-m-g/xlsx_drone_rb"