Merge pull request #1634 from chriseth/sol_overloadingFunctions

Function overloading.

4 files changed, 217 insertions, 26 deletions

diff --git a/libsolidity/SolidityEndToEndTest.cpp b/libsolidity/SolidityEndToEndTest.cpp
index db58c344..d5e6cc03 100644
--- a/libsolidity/SolidityEndToEndTest.cpp
+++ b/libsolidity/SolidityEndToEndTest.cpp
@@ -302,7 +302,6 @@ BOOST_AUTO_TEST_CASE(for_loop_simple_init_expr)
 
 BOOST_AUTO_TEST_CASE(calling_other_functions)
 {
-	// note that the index of a function is its index in the sorted sequence of functions
 	char const* sourceCode = "contract collatz {\n"
 							 "  function run(uint x) returns(uint y) {\n"
 							 "    while ((y = x) > 1) {\n"
@@ -1147,26 +1146,6 @@ BOOST_AUTO_TEST_CASE(now)
 	BOOST_CHECK(callContractFunction("someInfo()") == encodeArgs(true));
 }
 
-BOOST_AUTO_TEST_CASE(function_types)
-{
-	char const* sourceCode = "contract test {\n"
-							 "  function a(bool selector) returns (uint b) {\n"
-							 "    var f = fun1;\n"
-							 "    if (selector) f = fun2;\n"
-							 "    return f(9);\n"
-							 "  }\n"
-							 "  function fun1(uint x) returns (uint b) {\n"
-							 "    return 11;\n"
-							 "  }\n"
-							 "  function fun2(uint x) returns (uint b) {\n"
-							 "    return 12;\n"
-							 "  }\n"
-							 "}\n";
-	compileAndRun(sourceCode);
-	BOOST_CHECK(callContractFunction("a(bool)", false) == encodeArgs(11));
-	BOOST_CHECK(callContractFunction("a(bool)", true) == encodeArgs(12));
-}
-
 BOOST_AUTO_TEST_CASE(type_conversions_cleanup)
 {
 	// 22-byte integer converted to a contract (i.e. address, 20 bytes), converted to a 32 byte
@@ -3674,6 +3653,94 @@ BOOST_AUTO_TEST_CASE(packed_storage_structs_with_bytes0)
 	BOOST_CHECK(callContractFunction("test()") == encodeArgs(true));
 }
 
+BOOST_AUTO_TEST_CASE(overloaded_function_call_resolve_to_first)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f(uint k) returns(uint d) { return k; }
+			function f(uint a, uint b) returns(uint d) { return a + b; }
+			function g() returns(uint d) { return f(3); }
+		}
+	)";
+	compileAndRun(sourceCode);
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(3));
+}
+
+BOOST_AUTO_TEST_CASE(overloaded_function_call_resolve_to_second)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f(uint a, uint b) returns(uint d) { return a + b; }
+			function f(uint k) returns(uint d) { return k; }
+			function g() returns(uint d) { return f(3, 7); }
+		}
+	)";
+	compileAndRun(sourceCode);
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(10));
+}
+
+BOOST_AUTO_TEST_CASE(overloaded_function_call_with_if_else)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f(uint a, uint b) returns(uint d) { return a + b; }
+			function f(uint k) returns(uint d) { return k; }
+			function g(bool flag) returns(uint d) {
+				if (flag)
+					return f(3);
+				else
+					return f(3, 7);
+			}
+		}
+	)";
+	compileAndRun(sourceCode);
+	BOOST_CHECK(callContractFunction("g(bool)", true) == encodeArgs(3));
+	BOOST_CHECK(callContractFunction("g(bool)", false) == encodeArgs(10));
+}
+
+BOOST_AUTO_TEST_CASE(derived_overload_base_function_direct)
+{
+	char const* sourceCode = R"(
+		contract B { function f() returns(uint) { return 10; } }
+		contract C is B {
+			function f(uint i) returns(uint) { return 2 * i; }
+			function g() returns(uint) { return f(1); }
+		}
+	)";
+	compileAndRun(sourceCode, 0, "C");
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(2));
+}
+
+BOOST_AUTO_TEST_CASE(derived_overload_base_function_indirect)
+{
+	char const* sourceCode = R"(
+		contract A { function f(uint a) returns(uint) { return 2 * a; } }
+		contract B { function f() returns(uint) { return 10; } }
+		contract C is A, B {
+			function g() returns(uint) { return f(); }
+			function h() returns(uint) { return f(1); }
+		}
+	)";
+	compileAndRun(sourceCode, 0, "C");
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(10));
+	BOOST_CHECK(callContractFunction("h()") == encodeArgs(2));
+}
+
+BOOST_AUTO_TEST_CASE(super_overload)
+{
+	char const* sourceCode = R"(
+		contract A { function f(uint a) returns(uint) { return 2 * a; } }
+		contract B { function f(bool b) returns(uint) { return 10; } }
+		contract C is A, B {
+			function g() returns(uint) { return super.f(true); }
+			function h() returns(uint) { return super.f(1); }
+		}
+	)";
+	compileAndRun(sourceCode, 0, "C");
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(10));
+	BOOST_CHECK(callContractFunction("h()") == encodeArgs(2));
+}
+
 BOOST_AUTO_TEST_CASE(packed_storage_signed)
 {
 	char const* sourceCode = R"(
diff --git a/libsolidity/SolidityExpressionCompiler.cpp b/libsolidity/SolidityExpressionCompiler.cpp
index 613b0b1f..b2436cfa 100644
--- a/libsolidity/SolidityExpressionCompiler.cpp
+++ b/libsolidity/SolidityExpressionCompiler.cpp
@@ -78,7 +78,9 @@ Declaration const& resolveDeclaration(
 	// bracers are required, cause msvc couldnt handle this macro in for statement
 	for (string const& namePart: _namespacedName)
 	{
-		BOOST_REQUIRE(declaration = _resolver.resolveName(namePart, declaration));
+		auto declarations = _resolver.resolveName(namePart, declaration);
+		BOOST_REQUIRE(!declarations.empty());
+		BOOST_REQUIRE(declaration = *declarations.begin());
 	}
 	BOOST_REQUIRE(declaration);
 	return *declaration;
diff --git a/libsolidity/SolidityNameAndTypeResolution.cpp b/libsolidity/SolidityNameAndTypeResolution.cpp
index 076ea595..c317dad9 100644
--- a/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -623,23 +623,23 @@ BOOST_AUTO_TEST_CASE(cyclic_inheritance)
 	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
 }
 
-BOOST_AUTO_TEST_CASE(illegal_override_direct)
+BOOST_AUTO_TEST_CASE(legal_override_direct)
 {
 	char const* text = R"(
 		contract B { function f() {} }
 		contract C is B { function f(uint i) {} }
 	)";
-	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
+	BOOST_CHECK_NO_THROW(parseTextAndResolveNames(text));
 }
 
-BOOST_AUTO_TEST_CASE(illegal_override_indirect)
+BOOST_AUTO_TEST_CASE(legal_override_indirect)
 {
 	char const* text = R"(
 		contract A { function f(uint a) {} }
 		contract B { function f() {} }
 		contract C is A, B { }
 	)";
-	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
+	BOOST_CHECK_NO_THROW(parseTextAndResolveNames(text));
 }
 
 BOOST_AUTO_TEST_CASE(illegal_override_visibility)
@@ -1654,6 +1654,103 @@ BOOST_AUTO_TEST_CASE(bytes0_array)
 	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
 }
 
+BOOST_AUTO_TEST_CASE(overloaded_function_cannot_resolve)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f() returns(uint) { return 1; }
+			function f(uint a) returns(uint) { return a; }
+			function g() returns(uint) { return f(3, 5); }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(ambiguous_overloaded_function)
+{
+	// literal 1 can be both converted to uint and uint8, so the call is ambiguous.
+	char const* sourceCode = R"(
+		contract test {
+			function f(uint8 a) returns(uint) { return a; }
+			function f(uint a) returns(uint) { return 2*a; }
+			function g() returns(uint) { return f(1); }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(assignment_of_nonoverloaded_function)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f(uint a) returns(uint) { return 2 * a; }
+			function g() returns(uint) { var x = f; return x(7); }
+		}
+	)";
+	ETH_TEST_REQUIRE_NO_THROW(parseTextAndResolveNames(sourceCode), "Type resolving failed");
+}
+
+BOOST_AUTO_TEST_CASE(assignment_of_overloaded_function)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function f() returns(uint) { return 1; }
+			function f(uint a) returns(uint) { return 2 * a; }
+			function g() returns(uint) { var x = f; return x(7); }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(external_types_clash)
+{
+	char const* sourceCode = R"(
+		contract base {
+			enum a { X }
+			function f(a) { }
+		}
+		contract test is base {
+			function f(uint8 a) { }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(override_changes_return_types)
+{
+	char const* sourceCode = R"(
+		contract base {
+			function f(uint a) returns (uint) { }
+		}
+		contract test is base {
+			function f(uint a) returns (uint8) { }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(multiple_constructors)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function test(uint a) { }
+			function test() {}
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), DeclarationError);
+}
+
+BOOST_AUTO_TEST_CASE(equal_overload)
+{
+	char const* sourceCode = R"(
+		contract test {
+			function test(uint a) returns (uint b) { }
+			function test(uint a) external {}
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), DeclarationError);
+}
+
 BOOST_AUTO_TEST_CASE(uninitialized_var)
 {
 	char const* sourceCode = R"(
diff --git a/libsolidity/SolidityParser.cpp b/libsolidity/SolidityParser.cpp
index ad17c40a..cad0e1f2 100644
--- a/libsolidity/SolidityParser.cpp
+++ b/libsolidity/SolidityParser.cpp
@@ -134,6 +134,31 @@ BOOST_AUTO_TEST_CASE(missing_argument_in_named_args)
 	BOOST_CHECK_THROW(parseText(text), ParserError);
 }
 
+BOOST_AUTO_TEST_CASE(two_exact_functions)
+{
+	char const* text = R"(
+		contract test {
+			function fun(uint a) returns(uint r) { return a; }
+			function fun(uint a) returns(uint r) { return a; }
+		}
+	)";
+	// with support of overloaded functions, during parsing,
+	// we can't determine whether they match exactly, however
+	// it will throw DeclarationError in following stage.
+	BOOST_CHECK_NO_THROW(parseText(text));
+}
+
+BOOST_AUTO_TEST_CASE(overloaded_functions)
+{
+	char const* text = R"(
+		contract test {
+			function fun(uint a) returns(uint r) { return a; }
+			function fun(uint a, uint b) returns(uint r) { return a + b; }
+		}
+	)";
+	BOOST_CHECK_NO_THROW(parseText(text));
+}
+
 BOOST_AUTO_TEST_CASE(function_natspec_documentation)
 {
 	ASTPointer<ContractDefinition> contract;