Add treat_numeric_as_conflict option to prevent ambiguous numeric slugs

lib/friendly_id/slug_generator.rb

@@ -12,12 +12,28 @@ def available?(slug)
         return false if @config.reserved_words.include?(slug)
       end
 
+      if @config.treat_numeric_as_conflict && purely_numeric_slug?(slug)
+        return false
+      end
+
       !@scope.exists_by_friendly_id?(slug)
     end
 
     def generate(candidates)
       candidates.each { |c| return c if available?(c) }
       nil
     end
+
+    private
+
+    def purely_numeric_slug?(slug)
+      return false unless slug
+      begin
+        Integer(slug, 10)
+        slug.to_s == Integer(slug, 10).to_s
+      rescue
+        false
+      end
+    end
   end
 end

lib/friendly_id/slugged.rb

@@ -386,7 +386,7 @@ def unset_slug_if_invalid
     # {FriendlyId::Configuration FriendlyId::Configuration}.
     module Configuration
       attr_writer :slug_column, :slug_limit, :sequence_separator
-      attr_accessor :slug_generator_class
+      attr_accessor :slug_generator_class, :treat_numeric_as_conflict
 
       # Makes FriendlyId use the slug column for querying.
       # @return String The slug column.

test/numeric_slug_test.rb

@@ -1,5 +1,17 @@
 require "helper"
 
+class Article < ActiveRecord::Base
+  extend FriendlyId
+  friendly_id :name, use: :slugged
+end
+
+class ArticleWithNumericPrevention < ActiveRecord::Base
+  self.table_name = "articles"
+  extend FriendlyId
+  friendly_id :name, use: :slugged
+  friendly_id_config.treat_numeric_as_conflict = true
+end
+
 class NumericSlugTest < TestCaseClass
   include FriendlyId::Test
   include FriendlyId::Test::Shared::Core
@@ -28,4 +40,61 @@ def model_class
       assert model_class.friendly.exists?("123")
     end
   end
+
+  test "should prevent purely numeric slugs when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "123"
+      refute_equal "123", record.slug
+      assert_match(/\A123-[0-9a-f-]{36}\z/, record.slug)
+    end
+  end
+
+  test "should allow non-numeric slugs when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "abc123"
+      assert_equal "abc123", record.slug
+    end
+  end
+
+  test "should allow alphanumeric slugs when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "product-123"
+      assert_equal "product-123", record.slug
+    end
+  end
+
+  test "should handle zero as numeric when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "0"
+      refute_equal "0", record.slug
+      assert_match(/\A0-[0-9a-f-]{36}\z/, record.slug)
+    end
+  end
+
+  test "should handle large numbers as numeric when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "999999999"
+      refute_equal "999999999", record.slug
+      assert_match(/\A999999999-[0-9a-f-]{36}\z/, record.slug)
+    end
+  end
+
+  test "should find records with UUID-suffixed numeric slugs when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record = ArticleWithNumericPrevention.create! name: "123"
+      found = ArticleWithNumericPrevention.friendly.find(record.slug)
+      assert_equal record.id, found.id
+    end
+  end
+
+  test "should resolve conflicts between multiple numeric slugs when treat_numeric_as_conflict is enabled" do
+    transaction do
+      record1 = ArticleWithNumericPrevention.create! name: "456"
+      record2 = ArticleWithNumericPrevention.create! name: "456"
+
+      refute_equal record1.slug, record2.slug
+      assert_match(/\A456-[0-9a-f-]{36}\z/, record1.slug)
+      assert_match(/\A456-[0-9a-f-]{36}\z/, record2.slug)
+    end
+  end
 end