8 files changed, 9 insertions, 9 deletions
diff --git a/lib/axlsx/drawing/axes.rb b/lib/axlsx/drawing/axes.rb
index 6a74c879..010fe8cd 100644
--- a/lib/axlsx/drawing/axes.rb
+++ b/lib/axlsx/drawing/axes.rb
@@ -32,7 +32,7 @@ module Axlsx
     def to_xml_string(str = +'', options = {})
       if options[:ids]
         # CatAxis must come first in the XML (for Microsoft Excel at least)
-        sorted = axes.sort_by { |name, axis| axis.kind_of?(CatAxis) ? 0 : 1 }
+        sorted = axes.sort_by { |name, axis| axis.is_a?(CatAxis) ? 0 : 1 }
         sorted.each { |axis| str << '<c:axId val="' << axis[1].id.to_s << '"/>' }
       else
         axes.each { |axis| axis[1].to_xml_string(str) }
diff --git a/lib/axlsx/drawing/d_lbls.rb b/lib/axlsx/drawing/d_lbls.rb
index 8965599c..7e3936cc 100644
--- a/lib/axlsx/drawing/d_lbls.rb
+++ b/lib/axlsx/drawing/d_lbls.rb
@@ -76,7 +76,7 @@ module Axlsx
       str << '<c:dLbls>'
       instance_vals = Axlsx.instance_values_for(self)
       %w(d_lbl_pos show_legend_key show_val show_cat_name show_ser_name show_percent show_bubble_size show_leader_lines).each do |key|
-        next unless instance_vals.key?(key) && instance_vals[key] != nil
+        next unless instance_vals.key?(key) && !instance_vals[key].nil?
 
         str << "<c:#{Axlsx::camel(key, false)} val='#{instance_vals[key]}' />"
       end
diff --git a/lib/axlsx/util/mime_type_utils.rb b/lib/axlsx/util/mime_type_utils.rb
index c2e6909f..fbe39448 100644
--- a/lib/axlsx/util/mime_type_utils.rb
+++ b/lib/axlsx/util/mime_type_utils.rb
@@ -16,7 +16,7 @@ module Axlsx
     # @param [String] v URI
     # @return [String] File mime type
     def self.get_mime_type_from_uri(v)
-      Marcel::MimeType.for(URI.open(v))
+      Marcel::MimeType.for(URI.parse(v).open)
     end
   end
 end
diff --git a/lib/axlsx/workbook/worksheet/col.rb b/lib/axlsx/workbook/worksheet/col.rb
index 539a6007..ff942d32 100644
--- a/lib/axlsx/workbook/worksheet/col.rb
+++ b/lib/axlsx/workbook/worksheet/col.rb
@@ -114,7 +114,7 @@ module Axlsx
       # current @width value.
       # TODO!!!
       # Axlsx.validate_unsigned_numeric(v) unless v == nil
-      @custom_width = @best_fit = v != nil
+      @custom_width = @best_fit = !v.nil?
       @width = v.nil? ? v : [v, MAX_WIDTH].min
     end
 
diff --git a/lib/axlsx/workbook/worksheet/page_setup.rb b/lib/axlsx/workbook/worksheet/page_setup.rb
index 0bd0cdb8..6fc8ccba 100644
--- a/lib/axlsx/workbook/worksheet/page_setup.rb
+++ b/lib/axlsx/workbook/worksheet/page_setup.rb
@@ -225,8 +225,8 @@ module Axlsx
     # We treat any page set up that has a value set for fit_to_width or fit_to_height value as fit_to_page.
     # @return [Boolean]
     def fit_to_page?
-      # is there some better what to express this?
-      (fit_to_width != nil || fit_to_height != nil)
+      # is there some better way to express this?
+      (!fit_to_width.nil? || !fit_to_height.nil?)
     end
 
     # Serializes the page settings element.
diff --git a/lib/axlsx/workbook/worksheet/pane.rb b/lib/axlsx/workbook/worksheet/pane.rb
index a018dc74..6cab87b9 100644
--- a/lib/axlsx/workbook/worksheet/pane.rb
+++ b/lib/axlsx/workbook/worksheet/pane.rb
@@ -108,7 +108,7 @@ module Axlsx
 
     # @see top_left_cell
     def top_left_cell=(v)
-      cell = (v.class == Axlsx::Cell ? v.r_abs : v)
+      cell = (v.instance_of?(Axlsx::Cell) ? v.r_abs : v)
       Axlsx::validate_string(cell)
       @top_left_cell = cell
     end
diff --git a/lib/axlsx/workbook/worksheet/selection.rb b/lib/axlsx/workbook/worksheet/selection.rb
index 556651e3..1a2633b4 100644
--- a/lib/axlsx/workbook/worksheet/selection.rb
+++ b/lib/axlsx/workbook/worksheet/selection.rb
@@ -74,7 +74,7 @@ module Axlsx
 
     # @see active_cell
     def active_cell=(v)
-      cell = (v.class == Axlsx::Cell ? v.r_abs : v)
+      cell = (v.instance_of?(Axlsx::Cell) ? v.r_abs : v)
       Axlsx::validate_string(cell)
       @active_cell = cell
     end
diff --git a/lib/axlsx/workbook/worksheet/sheet_view.rb b/lib/axlsx/workbook/worksheet/sheet_view.rb
index d06715fe..73e7533e 100644
--- a/lib/axlsx/workbook/worksheet/sheet_view.rb
+++ b/lib/axlsx/workbook/worksheet/sheet_view.rb
@@ -166,7 +166,7 @@ module Axlsx
 
     # @see top_left_cell
     def top_left_cell=(v)
-      cell = (v.class == Axlsx::Cell ? v.r_abs : v)
+      cell = (v.instance_of?(Axlsx::Cell) ? v.r_abs : v)
       Axlsx::validate_string(cell)
       @top_left_cell = cell
     end