RUBY 3212 pafs proposals with duplicate names are not sent to pipeline (

#903)

* [RUBY-3212] Add validation for unique project names in `PafsCore::ProjectNameStep` spec

- Added a new context to test for duplicate project names.
- Ensures that the model returns false and sets an error message when a duplicate project name is provided.

* [RUBY-3212] Refactor `name_must_be_unique` method for readability

- Simplified `name_must_be_unique` method using `return unless` to improve readability and reduce nesting.

* [RUBY-3220] Add back shared example to `project_name_step_spec.rb`

* [RUBY-3212] Refactor project name uniqueness validation in spec

- Moved the creation of `existing_project` to a `before` block for better readability and consistency.

* [RUBY-3212] Add unique index to `projects` name

- Created migration to add unique index to `pafs_core_projects` table on the `name` column.
- Updated schema to reflect the new unique index on the `name` column.

* [RUBY-3212] Update migration class to inherit from ActiveRecord::Migration[7.1]

- Changed inheritance of `AddUniqueIndexToProjectsName` from `ActiveRecord::Migration[7.2]` to `ActiveRecord::Migration[7.1]`

* [RUBY-3212] Remove redundant assignment in `project_name_step` uniqueness test

app/steps/pafs_core/project_name_step.rb

@@ -11,10 +11,20 @@ class ProjectNameStep < BasicStep
       message: "The project name must only contain letters, underscores, hyphens and numbers"
     }, if: -> { name.present? }
 
+    validate :name_must_be_unique
+
     private
 
     def step_params(params)
       params.require(:project_name_step).permit(:name)
     end
+
+    # BasicStep does not have access to the uniqueness validator presumably
+    # because it's not an ActiveRecord model. So we need to implement our own
+    def name_must_be_unique
+      return unless PafsCore::Project.exists?(name: name)
+
+      errors.add(:name, "The project name already exists. Your project must have a unique name.")
+    end
   end
 end

db/migrate/20240904104418_add_unique_index_to_projects_name.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddUniqueIndexToProjectsName < ActiveRecord::Migration[7.1]
+  def change
+    add_index :pafs_core_projects, :name, unique: true
+  end
+end

spec/dummy/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2024_03_27_113556) do
+ActiveRecord::Schema[7.1].define(version: 2024_09_04_104418) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -328,6 +328,7 @@
     t.integer "earliest_start_year"
     t.string "updated_by_type"
     t.bigint "updated_by_id"
+    t.index ["name"], name: "index_pafs_core_projects_on_name", unique: true
     t.index ["reference_number", "version"], name: "index_pafs_core_projects_on_reference_number_and_version", unique: true
     t.index ["slug"], name: "index_pafs_core_projects_on_slug", unique: true
     t.index ["submitted_to_pol"], name: "index_pafs_core_projects_on_submitted_to_pol"
@@ -398,5 +399,4 @@
     t.index ["reset_password_token"], name: "index_pafs_core_users_on_reset_password_token", unique: true
     t.index ["unlock_token"], name: "index_pafs_core_users_on_unlock_token", unique: true
   end
-
 end

spec/steps/pafs_core/project_name_step_spec.rb

@@ -44,5 +44,16 @@
         end
       end
     end
+
+    context "when name already exists" do
+      let(:duplicate_name_params) { ActionController::Parameters.new({ project_name_step: { name: "Unique Project Name" } }) }
+
+      before { create(:project_name_step, name: "Unique Project Name") }
+
+      it "returns false and sets the uniqueness error message" do
+        expect(project_name_step.update(duplicate_name_params)).to be false
+        expect(project_name_step.errors[:name].join).to eq("The project name already exists. Your project must have a unique name.")
+      end
+    end
   end
 end