Always round coverage percentage down, never up

When the coverage percentage is rounded up, people may end up
misconfiguring SimpleCov with a number that 0.01 too high. They may even
think they have a 100% converage, when in fact the coverage is only
marginally higher than 99.995%.

This commit changes all uses of `#round` for  `#floor`, thus always
rounding _down_ and never _up_.

Author: bquorning

lib/simplecov-html.rb

@@ -55,8 +55,9 @@ def line_status?(source_file, line)
 
       def output_message(result)
         output = "Coverage report generated for #{result.command_name} to #{output_path}."
-        output += "\nLine Coverage: #{result.covered_percent.round(2)}% (#{result.covered_lines} / #{result.total_lines})"
-        output += "\nBranch Coverage: #{result.coverage_statistics[:branch].percent.round(2)}% (#{result.covered_branches} / #{result.total_branches})" if branchable_result?
+        output += "\nLine Coverage: #{result.covered_percent.floor(2)}% (#{result.covered_lines} / #{result.total_lines})"
+
+        output += "\nBranch Coverage: #{result.coverage_statistics[:branch].percent.floor(2)}% (#{result.covered_branches} / #{result.total_branches})" if branchable_result?
         output
       end
 

test/test_simple_cov-html.rb

@@ -170,28 +170,28 @@ def test_output # rubocop:disable Metrics
                                 "uneven_nocovs.rb" => coverage_for_uneven_nocov_rb,
                               })
 
-    # All Files ( 74.12% covered at 0.84 hits/line )
+    # All Files ( 74.11% covered at 0.83 hits/line )
     header_line_coverage = html_doc.at_css("div#AllFiles span.covered_percent span").content.strip
 
-    assert_equal("74.12%", header_line_coverage)
+    assert_equal("74.11%", header_line_coverage)
 
-    # 85 relevant lines, 63 lines covered and 22 lines missed. ( 74.12% )
+    # 85 relevant lines, 63 lines covered and 22 lines missed. ( 74.11% )
     subheader_line_coverage = html_doc.at_css("div#AllFiles div.t-line-summary span:last-child").content.strip
 
-    assert_equal("74.12%", subheader_line_coverage)
+    assert_equal("74.11%", subheader_line_coverage)
 
     if RUBY_ENGINE != "jruby"
-      # 58 total branches, 28 branches covered and 30 branches missed. ( 48.28% )
+      # 58 total branches, 28 branches covered and 30 branches missed. ( 48.27% )
       subheader_branch_coverage = html_doc.at_css("div#AllFiles div.t-branch-summary span:last-child").content.strip
 
-      assert_equal("48.28%", subheader_branch_coverage)
+      assert_equal("48.27%", subheader_branch_coverage)
     end
 
     sorted_line_coverages = [
       "57.14%",
-      "64.29%",
-      "66.67%",
-      "66.67%",
+      "64.28%",
+      "66.66%",
+      "66.66%",
       "80.00%",
       "85.71%",
       "85.71%",
@@ -229,7 +229,7 @@ def test_output # rubocop:disable Metrics
       assert_equal sorted_branch_coverages, all_files_table_branch_coverages.sort_by(&:to_f)
     end
 
-    # 66.67 lines covered
+    # 66.66 lines covered
     single_file_page_line_coverages = html_doc.css("div.source_files div.header h4:nth-child(2) span").map { |m| m.content.strip }
 
     assert_equal(sorted_line_coverages, single_file_page_line_coverages.sort_by(&:to_f))

views/covered_percent.erb

@@ -1,3 +1,3 @@
 <span class="<%= coverage_css_class(percent) %>">
-  <%= percent.round(2) %>%
+  <%= sprintf("%.2f", percent.floor(2)) %>%
 </span>

views/file_list.erb

@@ -7,7 +7,7 @@
      covered at
      <span class="covered_strength">
        <span class="<%= strength_css_class(source_files.covered_strength) %>">
-         <%= source_files.covered_strength.round(2) %>
+         <%= source_files.covered_strength %>
        </span>
     </span> hits/line
     )
@@ -58,14 +58,14 @@
         <% source_files.each do |source_file| %>
           <tr class="t-file">
             <td class="strong t-file__name"><%= link_to_source_file(source_file) %></td>
-            <td class="<%= coverage_css_class(source_file.covered_percent) %> strong cell--number t-file__coverage"><%= sprintf("%.2f", source_file.covered_percent.round(2)) %>%</td>
+            <td class="strong cell--number t-file__coverage"><%= covered_percent(source_file.covered_percent) %></td>
             <td class="cell--number"><%= source_file.lines.count %></td>
             <td class="cell--number"><%= source_file.covered_lines.count + source_file.missed_lines.count %></td>
             <td class="cell--number"><%= source_file.covered_lines.count %></td>
             <td class="cell--number"><%= source_file.missed_lines.count %></td>
             <td class="cell--number"><%= sprintf("%.2f", source_file.covered_strength.round(2)) %></td>
             <% if branchable_result? %>
-              <td class="<%= coverage_css_class(source_file.branches_coverage_percent) %> strong cell--number t-file__branch-coverage"><%= sprintf("%.2f", source_file.branches_coverage_percent.round(2)) %>%</td>
+              <td class="strong cell--number t-file__branch-coverage"><%= covered_percent(source_file.branches_coverage_percent) %></td>
               <td class="cell--number"><%= source_file.total_branches.count %></td>
               <td class="cell--number"><%= source_file.covered_branches.count %></td>
               <td class="cell--number"><%= source_file.missed_branches.count %></td>