1 files changed, 62 insertions, 0 deletions
diff --git a/lib/puppet/functions/validate_legacy.rb b/lib/puppet/functions/validate_legacy.rb
new file mode 100644
index 0000000..c9d1f56
--- /dev/null
+++ b/lib/puppet/functions/validate_legacy.rb
@@ -0,0 +1,62 @@
+Puppet::Functions.create_function(:validate_legacy) do
+  # The function checks a value against both the target_type (new) and the previous_validation function (old).
+
+  dispatch :validate_legacy do
+    param 'Any', :scope
+    param 'Type', :target_type
+    param 'String', :function_name
+    param 'Any', :value
+    repeated_param 'Any', :args
+  end
+
+  dispatch :validate_legacy_s do
+    param 'Any', :scope
+    param 'String', :type_string
+    param 'String', :function_name
+    param 'Any', :value
+    repeated_param 'Any', :args
+  end
+
+  # Workaround PUP-4438 (fixed: https://github.com/puppetlabs/puppet/commit/e01c4dc924cd963ff6630008a5200fc6a2023b08#diff-c937cc584953271bb3d3b3c2cb141790R221) to support puppet < 4.1.0 and puppet < 3.8.1.
+  def call(scope, *args)
+    manipulated_args = [scope] + args
+    self.class.dispatcher.dispatch(self, scope, manipulated_args)
+  end
+
+  def validate_legacy_s(scope, type_string, *args)
+    t = Puppet::Pops::Types::TypeParser.new.parse(type_string, scope)
+    validate_legacy(scope, t, *args)
+  end
+
+  def validate_legacy(scope, target_type, function_name, value, *prev_args)
+    if assert_type(target_type, value)
+      if previous_validation(scope, function_name, value, *prev_args)
+        # Silently passes
+      else
+        Puppet.notice("Accepting previously invalid value for target type '#{target_type}'")
+      end
+    else
+      inferred_type = Puppet::Pops::Types::TypeCalculator.infer_set(value)
+      error_msg = Puppet::Pops::Types::TypeMismatchDescriber.new.describe_mismatch("validate_legacy(#{function_name})", target_type, inferred_type)
+      if previous_validation(scope, function_name, value, *prev_args)
+        call_function('deprecation', 'validate_legacy', error_msg)
+      else
+        call_function('fail', error_msg)
+      end
+    end
+  end
+
+  def previous_validation(scope, function_name, value, *prev_args)
+    # Call the previous validation function and catch any errors. Return true if no errors are thrown.
+    begin
+      scope.send("function_#{function_name}".to_s, [value, *prev_args])
+      true
+    rescue Puppet::ParseError
+      false
+    end
+  end
+
+  def assert_type(type, value)
+    Puppet::Pops::Types::TypeCalculator.instance?(type, value)
+  end
+end