Add some tests

app/models/trip.rb

@@ -11,9 +11,9 @@ class Trip < ApplicationRecord
 
   def create_path!
     trip_path = Tracks::BuildPath.new(points.pluck(:latitude, :longitude)).call
-    distance = calculate_distance
 
-    update_columns(path: trip_path, distance: distance) # Avoids recursion with `after_save`
+    self.distance = calculate_distance
+    self.path = trip_path
   end
 
   def points

db/data/20250123151849_create_paths_for_trips.rb

@@ -2,6 +2,9 @@
 
 class CreatePathsForTrips < ActiveRecord::Migration[8.0]
   def up
+    Trip.find_each do |trip|
+      Trips::CreatePathJob.perform_later(trip.id)
+    end
   end
 
   def down

spec/factories/trips.rb

@@ -7,6 +7,8 @@ FactoryBot.define do
     started_at { DateTime.new(2024, 11, 27, 17, 16, 21) }
     ended_at { DateTime.new(2024, 11, 29, 17, 16, 21) }
     notes { FFaker::Lorem.sentence }
+    distance { 100 }
+    path { 'LINESTRING(1 1, 2 2, 3 3)' }
 
     trait :with_points do
       after(:build) do |trip|

spec/jobs/trips/create_path_job_spec.rb

@@ -1,5 +1,23 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 RSpec.describe Trips::CreatePathJob, type: :job do
-  pending "add some examples to (or delete) #{__FILE__}"
+  let!(:trip) { create(:trip, :with_points) }
+  let(:points) { trip.points }
+  let(:trip_path) do
+    "LINESTRING (#{points.map do |point|
+      "#{point.longitude.to_f.round(5)} #{point.latitude.to_f.round(5)}"
+    end.join(', ')})"
+  end
+
+  before do
+    trip.update(path: nil, distance: nil)
+  end
+
+  it 'creates a path for a trip' do
+    described_class.perform_now(trip.id)
+
+    expect(trip.reload.path.to_s).to eq(trip_path)
+  end
 end

spec/models/trip_spec.rb

@@ -21,6 +21,10 @@ RSpec.describe Trip, type: :model do
     it 'sets the distance' do
       expect(trip.distance).to eq(calculated_distance)
     end
+
+    it 'sets the path' do
+      expect(trip.path).to be_present
+    end
   end
 
   describe '#countries' do

spec/services/tracks/build_path_spec.rb

@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Tracks::BuildPath do
+  describe '#call' do
+    let(:coordinates) do
+      [
+        [45.123456, -122.654321], # [lat, lng]
+        [45.234567, -122.765432],
+        [45.345678, -122.876543]
+      ]
+    end
+
+    let(:service) { described_class.new(coordinates) }
+    let(:result) { service.call }
+
+    it 'returns an RGeo::Geographic::SphericalLineString' do
+      expect(result).to be_a(RGeo::Geographic::SphericalLineStringImpl)
+    end
+
+    it 'creates a line string with the correct number of points' do
+      expect(result.num_points).to eq(coordinates.length)
+    end
+
+    it 'correctly converts coordinates to points with rounded values' do
+      points = result.points
+
+      coordinates.each_with_index do |(lat, lng), index|
+        expect(points[index].x).to eq(lng.to_f.round(5))
+        expect(points[index].y).to eq(lat.to_f.round(5))
+      end
+    end
+  end
+end