Sketch out business logic and basic tests

test/models/rule_test.rb

@@ -0,0 +1,57 @@
+require "test_helper"
+
+class RuleTest < ActiveSupport::TestCase
+  include Account::EntriesTestHelper
+
+  setup do
+    @family = families(:empty)
+    @account = @family.accounts.create!(name: "Rule test", balance: 1000, currency: "USD", accountable: Depository.new)
+    @whole_foods_merchant = @family.merchants.create!(name: "Whole Foods")
+    @groceries_category = @family.categories.create!(name: "Groceries")
+  end
+
+  test "can apply categories to transactions" do
+    transaction_entry = create_transaction(date: Date.current, account: @account, merchant: @whole_foods_merchant)
+
+    rule = Rule.create!(
+      family: @family,
+      resource_type: "transaction",
+      effective_date: 1.day.ago.to_date,
+      conditions: [ Rule::Condition.new(condition_type: "match_merchant", operator: "eq", value: "Whole Foods") ],
+      actions: [ Rule::Action.new(action_type: "set_category", value: "Groceries") ]
+    )
+
+    rule.apply
+
+    transaction_entry.reload
+
+    assert_equal @groceries_category, transaction_entry.account_transaction.category
+  end
+
+  test "can create compound rules" do
+    transaction_entry1 = create_transaction(date: Date.current, amount: 50, account: @account, merchant: @whole_foods_merchant)
+    transaction_entry2 = create_transaction(date: Date.current, amount: 100, account: @account, merchant: @whole_foods_merchant)
+
+    # Assign "Groceries" to transactions with a merchant of "Whole Foods" and an amount greater than $60
+    rule = Rule.create!(
+      family: @family,
+      resource_type: "transaction",
+      effective_date: 1.day.ago.to_date,
+      conditions: [
+        Rule::Condition.new(condition_type: "compound", operator: "and", conditions: [
+          Rule::Condition.new(condition_type: "match_merchant", operator: "eq", value: "Whole Foods"),
+          Rule::Condition.new(condition_type: "compare_amount", operator: "gt", value: 60)
+        ])
+      ],
+      actions: [ Rule::Action.new(action_type: "set_category", value: "Groceries") ]
+    )
+
+    rule.apply
+
+    transaction_entry1.reload
+    transaction_entry2.reload
+
+    assert_nil transaction_entry1.account_transaction.category
+    assert_equal @groceries_category, transaction_entry2.account_transaction.category
+  end
+end