Added simple variable checking when validating translations.

app/models/tolk/translation.rb

@@ -8,6 +8,7 @@ class Translation < ActiveRecord::Base
 
     serialize :text
     validates_presence_of :text, :if => proc {|r| r.primary.blank? && !r.explicit_nil }
+    validate :check_matching_variables, :if => proc { |tr| tr.primary_translation.present? }
 
     validates_uniqueness_of :phrase_id, :scope => :locale_id
 
@@ -53,6 +54,23 @@ def value
       end
     end
 
+    def self.detect_variables(search_in)
+      case search_in
+        when String then Set.new(search_in.scan(/\{\{(\w+)\}\}/).flatten)
+        when Array then search_in.inject(Set[]) { |carry, item| carry + detect_variables(item) }
+        when Hash then search_in.values.inject(Set[]) { |carry, item| carry + detect_variables(item) }
+        else Set[]
+      end
+    end
+
+    def variables
+      self.class.detect_variables(text)
+    end
+
+    def variables_match?
+      self.variables == primary_translation.variables
+    end
+
     private
 
     def set_explicit_nil
@@ -89,5 +107,14 @@ def set_previous_text
       true
     end
 
+    def check_matching_variables
+      unless variables_match?
+        if primary_translation.variables.empty?
+          self.errors.add(:text, "The original does not contain variables, so they should not be included.")
+        else
+          self.errors.add(:text, "The translation should contain the variables #{variables.to_a.to_sentence}.")
+        end
+      end
+    end
   end
 end

test/locales/formats/en.yml

@@ -1,6 +1,11 @@
 en:
   number: 1
   string: I am just a stupid string :(
+  variables: "String with variables {{hello}} and {{world}}"
+  variables_in_struct:
+    zero: "Without variable"
+    one: "With {{variables}}"
+    other: "With even {{more}} {{variables}}"
   number_array: [1, 2, 3]
   string_array: ['sun', 'moon']
   pluralization:

test/unit/format_test.rb

@@ -60,6 +60,23 @@ def test_creating_translations_fails_on_mismatch_with_primary_translation
     success.save!
     assert_equal [1, 2], success.text
   end
+
+  def test_creating_translations_fails_with_unmatching_variables
+    # Check that variable detection works correctly
+    assert_equal Set['hello', 'world'], ph('variables').translations.primary.variables
+    assert_equal Set['more', 'variables'], ph('variables_in_struct').translations.primary.variables
+
+    # Allow different ordering and multiple occurences of variables
+    assert @spanish.translations.build(:text => '{{world}} y {{hello}} y {{hello}} y {{world}}', :phrase => ph('variables')).valid?
+
+    # Do not allow missing or wrong variables
+    assert_raises(ActiveRecord::RecordInvalid) { @spanish.translations.create!(:text => 'Hola', :phrase => ph('variables')) }
+    assert_raises(ActiveRecord::RecordInvalid) { @spanish.translations.create!(:text => '{{other}} variable', :phrase => ph('variables')) }
+
+    # Do not allow variables if the origin does not contain any
+    assert_equal Set[], ph('string').translations.primary.variables
+    assert_raises(ActiveRecord::RecordInvalid) { @spanish.translations.create!(:text => 'Hola {{mundo}}', :phrase => ph('string')) }
+  end
 
   def test_creating_translations_with_nil_values
     # implicit nil value