Allows sheet_for to accept an integer (#455)

* Allows sheet_for and default_sheet= to accept int

sheet_for and default_sheet= can now accept the sheet as integer and as
a string.

* Adds spec for sheet_for

lib/roo/base.rb

@@ -67,10 +67,10 @@ def default_sheet
   end
 
   # sets the working sheet in the document
-  # 'sheet' can be a number (1 = first sheet) or the name of a sheet.
+  # 'sheet' can be a number (0 = first sheet) or the name of a sheet.
   def default_sheet=(sheet)
     validate_sheet!(sheet)
-    @default_sheet = sheet
+    @default_sheet = sheet.is_a?(String) ? sheet : sheets[sheet]
     @first_row[sheet] = @last_row[sheet] = @first_column[sheet] = @last_column[sheet] = nil
     @cells_read[sheet] = false
   end
@@ -569,7 +569,7 @@ def validate_sheet!(sheet)
     when nil
       fail ArgumentError, "Error: sheet 'nil' not valid"
     when Integer
-      sheets.fetch(sheet - 1) do
+      sheets.fetch(sheet) do
         fail RangeError, "sheet index #{sheet} not found"
       end
     when String

lib/roo/excelx.rb

@@ -97,7 +97,7 @@ def sheets
     def sheet_for(sheet)
       sheet ||= default_sheet
       validate_sheet!(sheet)
-      @sheets_by_name[sheet]
+      @sheets_by_name[sheet] || @sheets[sheet]
     end
 
     def images(sheet = nil)

spec/lib/roo/base_spec.rb

@@ -127,10 +127,22 @@ def sheets
     end
   end
 
-  describe '#row' do
-    it 'should return the specified row' do
+  describe "#row" do
+    it "should return the specified row" do
       expect(spreadsheet.row(12)).to eq([41.0, 42.0, 43.0, 44.0, 45.0, nil, nil])
-      expect(spreadsheet.row(16)).to eq([nil, '"Hello world!"', 'forty-three', 'forty-four', 'forty-five', nil, nil])
+      expect(spreadsheet.row(16)).to eq([nil, '"Hello world!"', "forty-three", "forty-four", "forty-five", nil, nil])
+    end
+
+    it "should return the specified row if default_sheet is set by a string" do
+      spreadsheet.default_sheet = "my_sheet"
+      expect(spreadsheet.row(12)).to eq([41.0, 42.0, 43.0, 44.0, 45.0, nil, nil])
+      expect(spreadsheet.row(16)).to eq([nil, '"Hello world!"', "forty-three", "forty-four", "forty-five", nil, nil])
+    end
+
+    it "should return the specified row if default_sheet is set by an integer" do
+      spreadsheet.default_sheet = 0
+      expect(spreadsheet.row(12)).to eq([41.0, 42.0, 43.0, 44.0, 45.0, nil, nil])
+      expect(spreadsheet.row(16)).to eq([nil, '"Hello world!"', "forty-three", "forty-four", "forty-five", nil, nil])
     end
   end
 
@@ -173,6 +185,31 @@ def sheets
     end
   end
 
+  describe "#default_sheet=" do
+    it "should correctly set the default sheet if passed a string" do
+      spreadsheet.default_sheet = "my_sheet"
+      expect(spreadsheet.default_sheet).to eq("my_sheet")
+    end
+
+    it "should correctly set the default sheet if passed an integer" do
+      spreadsheet.default_sheet = 0
+      expect(spreadsheet.default_sheet).to eq("my_sheet")
+    end
+
+    it "should correctly set the default sheet if passed an integer for the second sheet" do
+      spreadsheet.default_sheet = 1
+      expect(spreadsheet.default_sheet).to eq("blank sheet")
+    end
+
+    it "should raise an error if passed a sheet that does not exist as an integer" do
+      expect { spreadsheet.default_sheet = 10 }.to raise_error RangeError
+    end
+
+    it "should raise an error if passed a sheet that does not exist as a string" do
+      expect { spreadsheet.default_sheet = "does_not_exist" }.to raise_error RangeError
+    end
+  end
+
   describe '#to_yaml' do
     it 'should convert the spreadsheet to yaml' do
       expect(spreadsheet.to_yaml({}, 5, 1, 5, 1)).to eq("--- \n" + yaml_entry(5, 1, 'date', '1961-11-21'))

spec/lib/roo/excelx_spec.rb

@@ -151,6 +151,22 @@
     it 'returns the expected result' do
       expect(subject.sheet_for("Tabelle1").instance_variable_get("@name")).to eq "Tabelle1"
     end
+
+    it 'returns the expected result when passed a number' do
+      expect(subject.sheet_for(0).instance_variable_get("@name")).to eq "Tabelle1"
+    end
+
+    it 'returns the expected result when passed a number that is not the first sheet' do
+      expect(subject.sheet_for(1).instance_variable_get("@name")).to eq "Name of Sheet 2"
+    end
+
+    it "should raise an error if passed a sheet that does not exist as an integer" do
+      expect { subject.sheet_for(10) }.to raise_error RangeError
+    end
+
+    it "should raise an error if passed a sheet that does not exist as a string" do
+      expect { subject.sheet_for("does_not_exist") }.to raise_error RangeError
+    end
   end
 
   describe '#row' do