DEV: Enhance unique name finder to handle fallback name conflicts

migrations/lib/importer/unique_name_finder_base.rb

@@ -18,7 +18,7 @@ module Migrations::Importer
     end
 
     def find_available_name(name)
-      name, name_lower = find_available_name_internal(name)
+      name, name_lower = resolve_unique_name(name)
       store_used_name(name_lower)
       name
     end
@@ -60,8 +60,8 @@ module Migrations::Importer
       false
     end
 
-    def find_available_name_internal(name)
-      name = sanitize_name(name)
+    def resolve_unique_name(original_name)
+      name = sanitize_name(original_name)
 
       result =
         if name.present?
@@ -141,13 +141,23 @@ module Migrations::Importer
     def find_fallback_name
       name = (@fallback_name ||= fallback_name)
       name_lower = name.downcase
-
       suffix = next_suffix(name_lower)
-      name_candidate = "#{name}_#{suffix}"
-      name_candidate_lower = name_candidate.downcase
+      attempts = 0
 
-      @last_suffixes[name_lower] = suffix
-      [name_candidate, name_candidate_lower]
+      while attempts < @max_attempts
+        name_candidate = "#{name}_#{suffix}"
+        name_candidate_lower = name_candidate.downcase
+
+        if name_available?(name_candidate_lower)
+          @last_suffixes[name_lower] = suffix
+          return name_candidate, name_candidate_lower
+        end
+
+        suffix += 1
+        attempts += 1
+      end
+
+      raise "Unable to find an available name after #{@max_attempts} attempts"
     end
 
     def next_suffix(name_lower)

migrations/spec/lib/importer/badge_name_finder_spec.rb

@@ -129,5 +129,21 @@ RSpec.describe Migrations::Importer::BadgeNameFinder do
         expect(name).to eq("Test & Badge!")
       end
     end
+
+    context "with fallback name conflicts" do
+      it "finds next available fallback name when some are already used" do
+        badge_rows << "badge_1"
+        badge_rows << "badge_123"
+
+        name1 = finder.find_available_name("")
+        119.times { finder.find_available_name("") }
+        name2 = finder.find_available_name("")
+        name3 = finder.find_available_name("")
+
+        expect(name1).to eq("Badge_2")
+        expect(name2).to eq("Badge_122")
+        expect(name3).to eq("Badge_124")
+      end
+    end
   end
 end

migrations/spec/lib/importer/category_name_finder_spec.rb

@@ -187,5 +187,21 @@ RSpec.describe Migrations::Importer::CategoryNameFinder do
         expect(name).to eq("Test & Category!")
       end
     end
+
+    context "with fallback name conflicts" do
+      it "finds next available fallback name when some are already used" do
+        category_rows << [nil, "category_1"]
+        category_rows << [nil, "category_123"]
+
+        name1 = finder.find_available_name("", nil)
+        119.times { finder.find_available_name("", nil) }
+        name2 = finder.find_available_name("", nil)
+        name3 = finder.find_available_name("", nil)
+
+        expect(name1).to eq("Category_2")
+        expect(name2).to eq("Category_122")
+        expect(name3).to eq("Category_124")
+      end
+    end
   end
 end

migrations/spec/lib/importer/group_name_finder_spec.rb

@@ -231,5 +231,22 @@ RSpec.describe Migrations::Importer::GroupNameFinder do
         expect(name).to eq("a_100")
       end
     end
+
+    context "with fallback name conflicts" do
+      it "finds next available fallback name when some are already used" do
+        fallback = I18n.t("importer.fallback_names.group")
+        group_names.add("#{fallback.downcase}_1")
+        group_names.add("#{fallback.downcase}_123")
+
+        name1 = finder.find_available_name("")
+        119.times { finder.find_available_name("") }
+        name2 = finder.find_available_name("")
+        name3 = finder.find_available_name("")
+
+        expect(name1).to eq("#{fallback}_2")
+        expect(name2).to eq("#{fallback}_122")
+        expect(name3).to eq("#{fallback}_124")
+      end
+    end
   end
 end

migrations/spec/lib/importer/username_finder_spec.rb

@@ -295,5 +295,22 @@ RSpec.describe Migrations::Importer::UsernameFinder do
         expect(username).to eq("a_100")
       end
     end
+
+    context "with fallback name conflicts" do
+      it "finds next available fallback name when some are already used" do
+        fallback = I18n.t("importer.fallback_names.user")
+        usernames.add("#{fallback.downcase}_1")
+        usernames.add("#{fallback.downcase}_123")
+
+        username1 = finder.find_available_name("")
+        119.times { finder.find_available_name("") }
+        username2 = finder.find_available_name("")
+        username3 = finder.find_available_name("")
+
+        expect(username1).to eq("#{fallback}_2")
+        expect(username2).to eq("#{fallback}_122")
+        expect(username3).to eq("#{fallback}_124")
+      end
+    end
   end
 end