Allow structs as part of function interfaces.

6 files changed, 280 insertions, 11 deletions

diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index 705d0f7f..3a93b74e 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -1770,7 +1770,7 @@ TypePointer StructType::interfaceType(bool _inLibrary) const
 	if (_inLibrary && location() == DataLocation::Storage)
 		return shared_from_this();
 	else
-		return TypePointer();
+		return copyForLocation(DataLocation::Memory, true);
 }
 
 TypePointer StructType::copyForLocation(DataLocation _location, bool _isPointer) const
diff --git a/libsolidity/interface/ABI.cpp b/libsolidity/interface/ABI.cpp
index 49df843d..7c7496cd 100644
--- a/libsolidity/interface/ABI.cpp
+++ b/libsolidity/interface/ABI.cpp
@@ -86,12 +86,12 @@ Json::Value ABI::generate(ContractDefinition const& _contractDef)
 		Json::Value params(Json::arrayValue);
 		for (auto const& p: it->parameters())
 		{
-			solAssert(!!p->annotation().type->interfaceType(false), "");
+			auto type = p->annotation().type->interfaceType(false);
+			solAssert(type, "");
 			Json::Value input;
-			input["name"] = p->name();
-			input["type"] = p->annotation().type->interfaceType(false)->canonicalName(false);
-			input["indexed"] = p->isIndexed();
-			params.append(input);
+			auto param = formatType(p->name(), *type, false);
+			param["indexed"] = p->isIndexed();
+			params.append(param);
 		}
 		event["inputs"] = params;
 		abi.append(event);
@@ -111,10 +111,50 @@ Json::Value ABI::formatTypeList(
 	for (unsigned i = 0; i < _names.size(); ++i)
 	{
 		solAssert(_types[i], "");
-		Json::Value param;
-		param["name"] = _names[i];
-		param["type"] = _types[i]->canonicalName(_forLibrary);
-		params.append(param);
+		params.append(formatType(_names[i], *_types[i], _forLibrary));
 	}
 	return params;
 }
+
+Json::Value ABI::formatType(string const& _name, Type const& _type, bool _forLibrary)
+{
+	Json::Value ret;
+	ret["name"] = _name;
+	if (_type.isValueType() || (_forLibrary && _type.dataStoredIn(DataLocation::Storage)))
+		ret["type"] = _type.canonicalName(_forLibrary);
+	else if (ArrayType const* arrayType = dynamic_cast<ArrayType const*>(&_type))
+	{
+		if (arrayType->isByteArray())
+			ret["type"] = _type.canonicalName(_forLibrary);
+		else
+		{
+			string suffix;
+			if (arrayType->isDynamicallySized())
+				suffix = "[]";
+			else
+				suffix = string("[") + arrayType->length().str() + "]";
+			solAssert(arrayType->baseType(), "");
+			Json::Value subtype = formatType("", *arrayType->baseType(), _forLibrary);
+			if (subtype["type"].isString() && !subtype.isMember("subtype"))
+				ret["type"] = subtype["type"].asString() + suffix;
+			else
+			{
+				ret["type"] = suffix;
+				solAssert(!subtype.isMember("subtype"), "");
+				ret["subtype"] = subtype["type"];
+			}
+		}
+	}
+	else if (StructType const* structType = dynamic_cast<StructType const*>(&_type))
+	{
+		ret["type"] = Json::arrayValue;
+		for (auto const& member: structType->members(nullptr))
+		{
+			solAssert(member.type, "");
+			ret["type"].append(formatType(member.name, *member.type, _forLibrary));
+		}
+	}
+	else
+		solAssert(false, "Invalid type.");
+	return ret;
+}
diff --git a/libsolidity/interface/ABI.h b/libsolidity/interface/ABI.h
index 95b162a9..7e42909b 100644
--- a/libsolidity/interface/ABI.h
+++ b/libsolidity/interface/ABI.h
@@ -50,6 +50,10 @@ private:
 		std::vector<TypePointer> const& _types,
 		bool _forLibrary
 	);
+	/// @returns a Json object with "name", "type" and potentially "subtype" keys, according
+	/// to the ABI specification.
+	/// If it is possible to express the type as a single string, it is allowed to return a single string.
+	static Json::Value formatType(std::string const& _name, Type const& _type, bool _forLibrary);
 };
 
 }
diff --git a/test/libsolidity/SolidityABIJSON.cpp b/test/libsolidity/SolidityABIJSON.cpp
index 4b9223de..7f03285d 100644
--- a/test/libsolidity/SolidityABIJSON.cpp
+++ b/test/libsolidity/SolidityABIJSON.cpp
@@ -48,7 +48,7 @@ public:
 
 		Json::Value generatedInterface = m_compilerStack.contractABI("");
 		Json::Value expectedInterface;
-		m_reader.parse(_expectedInterfaceString, expectedInterface);
+		BOOST_REQUIRE(m_reader.parse(_expectedInterfaceString, expectedInterface));
 		BOOST_CHECK_MESSAGE(
 			expectedInterface == generatedInterface,
 			"Expected:\n" << expectedInterface.toStyledString() <<
@@ -939,6 +939,140 @@ BOOST_AUTO_TEST_CASE(function_type)
 	checkInterface(sourceCode, interface);
 }
 
+BOOST_AUTO_TEST_CASE(return_structs)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; T[] sub; }
+			struct T { uint[2] x; }
+			function f() returns (uint x, S s) {
+			}
+		}
+	)";
+	char const* interface = R"(
+	[
+	{
+		"constant" : false,
+		"payable": false,
+		"inputs": [],
+		"name": "f",
+		"outputs": [{
+			"name": "x",
+			"type": "uint256"
+		}, {
+			"name": "s",
+			"type": [{
+				"name": "a",
+				"type": "uint256"
+			}, {
+				"name": "sub",
+				"subtype": [{
+					"name": "x",
+					"type": "uint256[2]"
+				}],
+				"type": "[]"
+			}]
+		}],
+		"type" : "function"
+	}
+	]
+	)";
+	checkInterface(text, interface);
+}
+
+BOOST_AUTO_TEST_CASE(event_structs)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; T[] sub; bytes b; }
+			struct T { uint[2] x; }
+			event E(T t, S s);
+		}
+	)";
+	char const* interface = R"(
+	[{
+		"anonymous" : false,
+		"inputs" : [{
+			"indexed" : false,
+			"name" : "t",
+			"type" : [{
+				"name" : "x",
+				"type" : "uint256[2]"
+			}]
+		}, {
+			"indexed" : false,
+			"name" : "s",
+			"type" : [{
+					"name" : "a",
+					"type" : "uint256"
+				}, {
+					"name" : "sub",
+					"subtype" : [{
+						"name" : "x",
+						"type" : "uint256[2]"
+					}],
+					"type" : "[]"
+				}, {
+					"name" : "b",
+					"type" : "bytes"
+				}]
+		}],
+		"name" : "E",
+		"type" : "event"
+	}]
+	)";
+	checkInterface(text, interface);
+}
+
+BOOST_AUTO_TEST_CASE(structs_in_libraries)
+{
+	char const* text = R"(
+		library L {
+			struct S { uint a; T[] sub; bytes b; }
+			struct T { uint[2] x; }
+			function f(L.S storage s) {}
+			function g(L.S s) {}
+		}
+	)";
+	char const* interface = R"(
+	[{
+		"constant" : false,
+		"inputs" : [{
+			"name" : "s",
+			"type" : [{
+				"name" : "a",
+				"type" : "uint256"
+			}, {
+				"name" : "sub",
+				"subtype" : [{
+					"name" : "x",
+					"type" : "uint256[2]"
+				}],
+				"type" : "[]"
+			}, {
+				"name" : "b",
+				"type" : "bytes"
+			}]
+		}],
+		"name" : "g",
+		"outputs" : [],
+		"payable" : false,
+		"type" : "function"
+	}, {
+		"constant" : false,
+		"inputs" : [{
+			"name" : "s",
+			"type" : "L.S storage"
+		}],
+		"name" : "f",
+		"outputs" : [],
+		"payable" : false,
+		"type" : "function"
+	}]
+	)";
+	checkInterface(text, interface);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }
diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp
index ea924fcb..6ea02673 100644
--- a/test/libsolidity/SolidityEndToEndTest.cpp
+++ b/test/libsolidity/SolidityEndToEndTest.cpp
@@ -9682,6 +9682,47 @@ BOOST_AUTO_TEST_CASE(contracts_separated_with_comment)
 	compileAndRun(sourceCode, 0, "C2");
 }
 
+BOOST_AUTO_TEST_CASE(return_structs)
+{
+	char const* sourceCode = R"(
+		contract C {
+			struct S { uint a; T[] sub; }
+			struct T { uint[2] x; }
+			function f() returns (uint x, S s) {
+				x = 7;
+				s.a = 8;
+				s.sub = new S[](3);
+				s.sub[0][0] = 9;
+				s.sub[1][0] = 10;
+				s.sub[2][1] = 11;
+			}
+		}
+	)";
+	compileAndRun(sourceCode, 0, "C");
+
+//	Will calculate the exact encoding later.
+//	BOOST_CHECK(callContractFunction("f()") == encodeArgs(
+//		u256(7), u256(0x40),
+//		u256(8), u256(0x40),
+//		u256(3),
+//		// s.sub[0]
+//		u256(9), u256(0xc0),
+//		// s.sub[1]
+//		u256(10), u256(0xe0),
+//		// s.sub[2]
+//		u256(11), u256(0x100),
+//		// s.sub[0].sub
+//		u256(2)
+//		// s.sub[0].sub[0].a
+//		u256(8),
+//		u256()
+//		// s.sub[1].sub
+//		u256(0)
+//		// s.sub[2].sub
+//		u256(2)
+//					));
+}
+
 BOOST_AUTO_TEST_CASE(include_creation_bytecode_only_once)
 {
 	char const* sourceCode = R"(
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index 8c271fe1..037bc9a0 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -5396,6 +5396,56 @@ BOOST_AUTO_TEST_CASE(constructible_internal_constructor)
 	success(text);
 }
 
+BOOST_AUTO_TEST_CASE(return_structs)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; T[] sub; }
+			struct T { uint[] x; }
+			function f() returns (uint x, S s) {
+			}
+		}
+	)";
+	success(text);
+}
+
+BOOST_AUTO_TEST_CASE(return_recursive_structs)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; S[] sub; }
+			function f() returns (uint x, S s) {
+			}
+		}
+	)";
+	success(text);
+}
+
+BOOST_AUTO_TEST_CASE(return_recursive_structs2)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; S[2] sub; }
+			function f() returns (uint x, S s) {
+			}
+		}
+	)";
+	CHECK_ERROR(text, TypeError, "recursive data types in external functions.");
+}
+
+BOOST_AUTO_TEST_CASE(return_recursive_structs3)
+{
+	char const* text = R"(
+		contract C {
+			struct S { uint a; S sub; }
+			struct T { S s; }
+			function f() returns (uint x, T t) {
+			}
+		}
+	)";
+	CHECK_ERROR(text, TypeError, "recursive data types in external functions.");
+}
+
 BOOST_AUTO_TEST_CASE(address_checksum_type_deduction)
 {
 	char const* text = R"(