Add tax treatment classification for investment accounts with international support (#693)

* Add tax treatment support for accounts, investments, and cryptos

* Replace hardcoded region labels with I18n translations

* Add I18n support for subtype labels with fallback to hardcoded values

* fixed schema

---------

Co-authored-by: luckyPipewrench <luckypipewrench@proton.me>

test/models/account_test.rb

@@ -89,4 +89,70 @@ class AccountTest < ActiveSupport::TestCase
     assert_equal "Investments", account.short_subtype_label
     assert_equal "Investments", account.long_subtype_label
   end
+
+  # Tax treatment tests (TaxTreatable concern)
+
+  test "tax_treatment delegates to accountable for Investment" do
+    investment = Investment.new(subtype: "401k")
+    account = @family.accounts.create!(
+      name: "Test 401k",
+      balance: 1000,
+      currency: "USD",
+      accountable: investment
+    )
+
+    assert_equal :tax_deferred, account.tax_treatment
+    assert_equal I18n.t("accounts.tax_treatments.tax_deferred"), account.tax_treatment_label
+  end
+
+  test "tax_treatment delegates to accountable for Crypto" do
+    crypto = Crypto.new(tax_treatment: :taxable)
+    account = @family.accounts.create!(
+      name: "Test Crypto",
+      balance: 500,
+      currency: "USD",
+      accountable: crypto
+    )
+
+    assert_equal :taxable, account.tax_treatment
+    assert_equal I18n.t("accounts.tax_treatments.taxable"), account.tax_treatment_label
+  end
+
+  test "tax_treatment returns nil for non-investment accounts" do
+    # Depository accounts don't have tax_treatment
+    assert_nil @account.tax_treatment
+    assert_nil @account.tax_treatment_label
+  end
+
+  test "tax_advantaged? returns true for tax-advantaged accounts" do
+    investment = Investment.new(subtype: "401k")
+    account = @family.accounts.create!(
+      name: "Test 401k",
+      balance: 1000,
+      currency: "USD",
+      accountable: investment
+    )
+
+    assert account.tax_advantaged?
+    assert_not account.taxable?
+  end
+
+  test "tax_advantaged? returns false for taxable accounts" do
+    investment = Investment.new(subtype: "brokerage")
+    account = @family.accounts.create!(
+      name: "Test Brokerage",
+      balance: 1000,
+      currency: "USD",
+      accountable: investment
+    )
+
+    assert_not account.tax_advantaged?
+    assert account.taxable?
+  end
+
+  test "taxable? returns true for accounts without tax_treatment" do
+    # Depository accounts
+    assert @account.taxable?
+    assert_not @account.tax_advantaged?
+  end
 end

test/models/crypto_test.rb

@@ -0,0 +1,30 @@
+require "test_helper"
+
+class CryptoTest < ActiveSupport::TestCase
+  test "tax_treatment defaults to taxable" do
+    crypto = Crypto.new
+    assert_equal "taxable", crypto.tax_treatment
+  end
+
+  test "tax_treatment can be set to tax_deferred" do
+    crypto = Crypto.new(tax_treatment: :tax_deferred)
+    assert_equal "tax_deferred", crypto.tax_treatment
+  end
+
+  test "tax_treatment can be set to tax_exempt" do
+    crypto = Crypto.new(tax_treatment: :tax_exempt)
+    assert_equal "tax_exempt", crypto.tax_treatment
+  end
+
+  test "tax_treatment enum provides predicate methods" do
+    crypto = Crypto.new(tax_treatment: :taxable)
+    assert crypto.taxable?
+    assert_not crypto.tax_deferred?
+    assert_not crypto.tax_exempt?
+
+    crypto.tax_treatment = :tax_deferred
+    assert_not crypto.taxable?
+    assert crypto.tax_deferred?
+    assert_not crypto.tax_exempt?
+  end
+end

test/models/investment_test.rb

@@ -0,0 +1,139 @@
+require "test_helper"
+
+class InvestmentTest < ActiveSupport::TestCase
+  # Tax treatment derivation tests
+
+  test "tax_treatment returns tax_deferred for US retirement accounts" do
+    %w[401k 403b 457b tsp ira sep_ira simple_ira].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  test "tax_treatment returns tax_exempt for Roth accounts" do
+    %w[roth_401k roth_ira].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_exempt, investment.tax_treatment, "Expected #{subtype} to be tax_exempt"
+    end
+  end
+
+  test "tax_treatment returns tax_advantaged for special accounts" do
+    %w[529_plan hsa].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_advantaged, investment.tax_treatment, "Expected #{subtype} to be tax_advantaged"
+    end
+  end
+
+  test "tax_treatment returns taxable for standard accounts" do
+    %w[brokerage mutual_fund angel trust ugma utma other].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :taxable, investment.tax_treatment, "Expected #{subtype} to be taxable"
+    end
+  end
+
+  test "tax_treatment returns taxable for nil subtype" do
+    investment = Investment.new(subtype: nil)
+    assert_equal :taxable, investment.tax_treatment
+  end
+
+  test "tax_treatment returns taxable for unknown subtype" do
+    investment = Investment.new(subtype: "unknown_type")
+    assert_equal :taxable, investment.tax_treatment
+  end
+
+  # UK account types
+
+  test "tax_treatment returns tax_exempt for UK ISA accounts" do
+    %w[isa lisa].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_exempt, investment.tax_treatment, "Expected #{subtype} to be tax_exempt"
+    end
+  end
+
+  test "tax_treatment returns tax_deferred for UK pension accounts" do
+    %w[sipp workplace_pension_uk].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  # Canadian account types
+
+  test "tax_treatment returns tax_deferred for Canadian retirement accounts" do
+    %w[rrsp lira rrif].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  test "tax_treatment returns tax_exempt for Canadian TFSA" do
+    investment = Investment.new(subtype: "tfsa")
+    assert_equal :tax_exempt, investment.tax_treatment
+  end
+
+  test "tax_treatment returns tax_advantaged for Canadian RESP" do
+    investment = Investment.new(subtype: "resp")
+    assert_equal :tax_advantaged, investment.tax_treatment
+  end
+
+  # Australian account types
+
+  test "tax_treatment returns tax_deferred for Australian super accounts" do
+    %w[super smsf].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  # European account types
+
+  test "tax_treatment returns tax_deferred for European pension accounts" do
+    %w[pillar_3a riester].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  test "tax_treatment returns tax_advantaged for French PEA" do
+    investment = Investment.new(subtype: "pea")
+    assert_equal :tax_advantaged, investment.tax_treatment
+  end
+
+  # Generic account types
+
+  test "tax_treatment returns tax_deferred for generic pension and retirement" do
+    %w[pension retirement].each do |subtype|
+      investment = Investment.new(subtype: subtype)
+      assert_equal :tax_deferred, investment.tax_treatment, "Expected #{subtype} to be tax_deferred"
+    end
+  end
+
+  # Subtype metadata tests
+
+  test "all subtypes have required metadata keys" do
+    Investment::SUBTYPES.each do |key, metadata|
+      assert metadata.key?(:short), "Subtype #{key} missing :short key"
+      assert metadata.key?(:long), "Subtype #{key} missing :long key"
+      assert metadata.key?(:tax_treatment), "Subtype #{key} missing :tax_treatment key"
+      assert metadata.key?(:region), "Subtype #{key} missing :region key"
+    end
+  end
+
+  test "all subtypes have valid tax_treatment values" do
+    valid_treatments = %i[taxable tax_deferred tax_exempt tax_advantaged]
+
+    Investment::SUBTYPES.each do |key, metadata|
+      assert_includes valid_treatments, metadata[:tax_treatment],
+        "Subtype #{key} has invalid tax_treatment: #{metadata[:tax_treatment]}"
+    end
+  end
+
+  test "all subtypes have valid region values" do
+    valid_regions = [ "us", "uk", "ca", "au", "eu", nil ]
+
+    Investment::SUBTYPES.each do |key, metadata|
+      assert_includes valid_regions, metadata[:region],
+        "Subtype #{key} has invalid region: #{metadata[:region]}"
+    end
+  end
+end