util.error: Add well-known field 'extra'

A place for various extra fields and edge cases of the stanza error data
model, e.g. the URI field of <gone>

2 files changed, 10 insertions, 0 deletions

diff --git a/spec/util_error_spec.lua b/spec/util_error_spec.lua
index ca053285..136f8b12 100644
--- a/spec/util_error_spec.lua
+++ b/spec/util_error_spec.lua
@@ -66,5 +66,13 @@ describe("util.error", function ()
 		end);
 	end);
 
+	describe("extra", function ()
+		it("keeps some extra fields", function ()
+			local err = errors.new({condition="gone",text="Sorry mate, it's all gone",extra={uri="file:///dev/null"}});
+			assert.is_table(err.extra);
+			assert.equal("file:///dev/null", err.extra.uri);
+		end);
+	end)
+
 end);
 
diff --git a/util/error.lua b/util/error.lua
index cfb35350..e0b1f9a6 100644
--- a/util/error.lua
+++ b/util/error.lua
@@ -43,6 +43,7 @@ local function new(e, context, registry, source)
 				type = e.type;
 				condition = e.condition;
 				text = e.text;
+				extra = e.extra;
 			};
 		else
 			template = {};
@@ -61,6 +62,7 @@ local function new(e, context, registry, source)
 		condition = template.condition or "undefined-condition";
 		text = template.text;
 		code = template.code;
+		extra = template.extra;
 
 		context = context;
 		source = source;