apply or remove legacy_deprecations to a block of code

this allows being explicit about if a code block is ready for the next gem update or not

lib/money/money.rb

@@ -115,16 +115,34 @@ def with_currency(new_currency, &block)
       Money.current_currency = old_currency
     end
 
-    def current_cross_currency_deprecation
-      Thread.current[:money_gem_cross_currency_deprecation]
+    def legacy_deprecations
+      Thread.current[:money_gem_legacy_deprecations] || reset_legacy_deprecations
     end
 
-    def cross_currency_deprecation(&block)
-      # Get cross-currency deprecation instead of exception
-      Thread.current[:money_gem_cross_currency_deprecation] = true
+    def disable_legacy_deprecations
+      Thread.current[:money_gem_legacy_deprecations] = false
+    end
+
+    def enable_legacy_deprecations
+      Thread.current[:money_gem_legacy_deprecations] = true
+    end
+
+    def reset_legacy_deprecations
+      Thread.current[:money_gem_legacy_deprecations] = Money.config.legacy_deprecations
+    end
+
+    def without_legacy_deprecations(&block)
+      disable_legacy_deprecations
+      yield
+    ensure
+      reset_legacy_deprecations
+    end
+
+    def with_legacy_deprecations(&block)
+      enable_legacy_deprecations
       yield
     ensure
-      Thread.current[:money_gem_cross_currency_deprecation] = false
+      reset_legacy_deprecations
     end
 
     private
@@ -143,7 +161,7 @@ def new_from_money(amount, currency)
       msg = "Money.new(Money.new(amount, #{amount.currency}), #{currency}) " \
         "is changing the currency of an existing money object"
 
-      if Money.current_cross_currency_deprecation
+      if Money.legacy_deprecations
         Money.deprecate("#{msg}. A Money::IncompatibleCurrencyError will raise in the next major release")
         Money.new(amount.value, currency)
       else
@@ -413,7 +431,7 @@ def arithmetic(other)
   def ensure_compatible_currency(other_currency, msg)
     return if currency.compatible?(other_currency)
 
-    if Money.current_cross_currency_deprecation
+    if Money.legacy_deprecations
       Money.deprecate("#{msg}. A Money::IncompatibleCurrencyError will raise in the next major release")
     else
       raise Money::IncompatibleCurrencyError, msg

spec/money_spec.rb

@@ -56,12 +56,18 @@
   end
 
   it "legacy_deprecations #to_money doesn't overwrite the money object's currency" do
-    Money.cross_currency_deprecation do
+    Money.with_legacy_deprecations do
       expect(Money).to receive(:deprecate).with(match(/to_money is attempting to change currency of an existing money object/)).once
       expect(Money.new(1, 'USD').to_money('CAD')).to eq(Money.new(1, 'USD'))
     end
   end
 
+  it "legacy_deprecations #to_money doesn't overwrite the money object's currency" do
+    Money.without_legacy_deprecations do
+      expect{ Money.new(1, 'USD').to_money('CAD') }.to raise_error(Money::IncompatibleCurrencyError)
+    end
+  end
+
   it "#to_money raises when changing currency" do
     expect{ Money.new(1, 'USD').to_money('CAD') }.to raise_error(Money::IncompatibleCurrencyError)
   end
@@ -102,7 +108,7 @@
   end
 
   it "legacy_deprecations constructor with money used the constructor currency" do
-    Money.cross_currency_deprecation do
+    Money.with_legacy_deprecations do
      expect(Money).to receive(:deprecate).with(match(/Money.new\(Money.new\(amount, USD\), CAD\) is changing the currency of an existing money object/)).once
       expect(Money.new(Money.new(1, 'USD'), 'CAD')).to eq(Money.new(1, 'CAD'))
     end
@@ -214,7 +220,7 @@
   end
 
   it "legacy_deprecations adds inconsistent currencies" do
-    Money.cross_currency_deprecation do
+    Money.with_legacy_deprecations do
       expect(Money).to receive(:deprecate).once
       expect(Money.new(5, 'USD') + Money.new(1, 'CAD')).to eq(Money.new(6, 'USD'))
     end
@@ -237,7 +243,7 @@
   end
 
   it "logs a deprecation warning when adding across currencies" do
-    Money.cross_currency_deprecation do
+    Money.with_legacy_deprecations do
       expect(Money).to receive(:deprecate).with(match(/mathematical operation not permitted for Money objects with different currencies/))
       expect(Money.new(10, 'USD') - Money.new(1, 'JPY')).to eq(Money.new(9, 'USD'))
     end
@@ -476,7 +482,7 @@
   it "generates a true rational" do
     expect(Money.rational(Money.new(10.0, 'USD'), Money.new(15.0, 'USD'))).to eq(Rational(2,3))
 
-    Money.cross_currency_deprecation do
+    Money.with_legacy_deprecations do
       expect(Money).to receive(:deprecate).once
       expect(Money.rational(Money.new(10.0, 'USD'), Money.new(15.0, 'JPY'))).to eq(Rational(2,3))
     end
@@ -562,7 +568,7 @@
     end
 
     it "<=> issues deprecation warning when comparing incompatible currency" do
-      Money.cross_currency_deprecation do
+      Money.with_legacy_deprecations do
         expect(Money).to receive(:deprecate).twice
         expect(Money.new(1000, 'USD') <=> Money.new(2000, 'JPY')).to eq(-1)
         expect(Money.new(2000, 'JPY') <=> Money.new(1000, 'USD')).to eq(1)
@@ -590,7 +596,7 @@
 
       describe('legacy different currencies') do
         around(:each) do |test|
-          Money.cross_currency_deprecation { test.run }
+          Money.with_legacy_deprecations { test.run }
         end
 
         it { expect(Money).to(receive(:deprecate).once); expect(cad_10 <=> usd_10).to(eq(0)) }