Add acronym support to Inflector; Issue #1366

2 files changed, 14 insertions, 10 deletions

diff --git a/activesupport/lib/active_support/inflector/inflections.rb b/activesupport/lib/active_support/inflector/inflections.rb
index 7091e19cbf..90bb62f57b 100644
--- a/activesupport/lib/active_support/inflector/inflections.rb
+++ b/activesupport/lib/active_support/inflector/inflections.rb
@@ -20,10 +20,10 @@ module ActiveSupport
         @__instance__ ||= new
       end
 
-      attr_reader :plurals, :singulars, :uncountables, :humans
+      attr_reader :plurals, :singulars, :uncountables, :humans, :acronyms, :acronym_regex
 
       def initialize
-        @plurals, @singulars, @uncountables, @humans, @acronyms = [], [], [], [], []
+        @plurals, @singulars, @uncountables, @humans, @acronyms, @acronym_regex = [], [], [], [], {}, /(?=a)b/
       end
 
       # Specifies a new acronym. An acronym must be specified as it will appear in a camelized string.  An underscore
@@ -73,7 +73,8 @@ module ActiveSupport
       #   underscore 'McDonald' #=> 'mcdonald'
       #   camelize 'mcdonald' #=> 'McDonald'
       def acronym(word)
-        @acronyms.unshift(word)
+        @acronyms[word.downcase] = word
+        @acronym_regex = /#{@acronyms.values.join("|")}/
       end
 
       # Specifies a new pluralization rule and its replacement. The rule can either be a string or a regular expression.
diff --git a/activesupport/lib/active_support/inflector/methods.rb b/activesupport/lib/active_support/inflector/methods.rb
index ae67ea6e49..3d28d33f40 100644
--- a/activesupport/lib/active_support/inflector/methods.rb
+++ b/activesupport/lib/active_support/inflector/methods.rb
@@ -65,12 +65,14 @@ module ActiveSupport
     # though there are cases where that does not hold:
     #
     #   "SSLError".underscore.camelize # => "SslError"
-    def camelize(lower_case_and_underscored_word, first_letter_in_uppercase = true)
-      if first_letter_in_uppercase
-        lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::#{$1.upcase}" }.gsub(/(?:^|_)(.)/) { $1.upcase }
+    def camelize(term, uppercase_first_letter = true)
+      string = term.to_s
+      if uppercase_first_letter
+        string = string.sub(/^[a-z\d]*/) { inflections.acronyms[$&] || $&.capitalize }
       else
-        lower_case_and_underscored_word.to_s[0].chr.downcase + camelize(lower_case_and_underscored_word)[1..-1]
+        string = string.sub(/^(?:#{inflections.acronym_regex}(?=\b|[A-Z_])|\w)/) { $&.downcase }
       end
+      string.gsub(/(?:_|(\/))([a-z\d]*)/i) { "#{$1}#{inflections.acronyms[$2] || $2.capitalize}" }.gsub('/', '::')
     end
 
     # Makes an underscored, lowercase form from the expression in the string.
@@ -88,7 +90,8 @@ module ActiveSupport
     def underscore(camel_cased_word)
       word = camel_cased_word.to_s.dup
       word.gsub!(/::/, '/')
-      word.gsub!(/([A-Z]+)([A-Z][a-z])/,'\1_\2')
+      word.gsub!(/(?:([A-Za-z\d])|^)(#{inflections.acronym_regex})(?=\b|[^a-z])/) { "#{$1}#{$1 && '_'}#{$2.downcase}" }
+      word.gsub!(/([A-Z\d]+)([A-Z][a-z])/,'\1_\2')
       word.gsub!(/([a-z\d])([A-Z])/,'\1_\2')
       word.tr!("-", "_")
       word.downcase!
@@ -103,9 +106,9 @@ module ActiveSupport
     #   "author_id"       # => "Author"
     def humanize(lower_case_and_underscored_word)
       result = lower_case_and_underscored_word.to_s.dup
-
       inflections.humans.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
-      result.gsub(/_id$/, "").gsub(/_/, " ").capitalize
+      result.gsub!(/_id$/, "")
+      result.gsub(/(_)?([a-z\d]*)/i) { "#{$1 && ' '}#{inflections.acronyms[$2] || $2.downcase}" }.gsub(/^\w/) { $&.upcase }
     end
 
     # Capitalizes all the words and replaces some characters in the string to create