Fix for convert_to won't recognize temperature aliases as temperatures …

…#251 (#252) Use generated regex for detecting temperatures instead of a hard-coded one when using `convert_to` with a String argument. Fixes #251 Co-authored-by: Kevin Olbrich <[email protected]>
olbrich · Aug 27, 2022 · 61a7cd7 · 61a7cd7
1 parent 3120be3
commit 61a7cd7
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/lib/ruby_units/unit.rb b/lib/ruby_units/unit.rb
@@ -351,6 +351,9 @@ def self.prefix_regex
       @@prefix_regex ||= @@prefix_map.keys.sort_by { |prefix| [prefix.length, prefix] }.reverse.join('|')
     end
 
+    # Generates (and memoizes) a regexp matching any of the temperature units or their aliases.
+    #
+    # @return [RegExp]
     def self.temp_regex
       @@temp_regex ||= begin
         temp_units = %w[tempK tempC tempF tempR degK degC degF degR]
@@ -1070,7 +1073,7 @@ def convert_to(other)
       return self if TrueClass === other
       return self if FalseClass === other
 
-      if (other.is_a?(Unit) && other.temperature?) || (other.is_a?(String) && other =~ /temp[CFRK]/)
+      if (other.is_a?(Unit) && other.temperature?) || (other.is_a?(String) && other =~ self.class.temp_regex)
         raise ArgumentError, 'Receiver is not a temperature unit' unless degree?
 
         start_unit = units

diff --git a/spec/ruby_units/temperature_spec.rb b/spec/ruby_units/temperature_spec.rb
@@ -1,7 +1,7 @@
 require File.dirname(__FILE__) + '/../spec_helper'
 
 describe 'temperatures' do
-  describe 'redfine display name' do
+  describe 'redefine display name' do
     before(:all) do
       Unit.redefine!('tempC') do |c|
         c.aliases = %w[tC tempC]
@@ -106,6 +106,9 @@
       specify { expect(RubyUnits::Unit.new('100 tK').convert_to('tempR')).to be_within(RubyUnits::Unit.new('0.01 degR')).of(RubyUnits::Unit.new('180 tempR')) }
 
       specify { expect(RubyUnits::Unit.new('32 tF').convert_to('tempC')).to eq(RubyUnits::Unit.new('0 tC')) }
+
+      # See https://github.com/olbrich/ruby-units/issues/251
+      specify { expect(RubyUnits::Unit.new('32 tF').convert_to('tC')).to eq(RubyUnits::Unit.new('0 tC')) }
     end
   end
 end