Add implicit convertibility to function pointer with higher state mutability

4 files changed, 178 insertions, 0 deletions

diff --git a/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_fail.sol b/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_fail.sol
new file mode 100644
index 00000000..0d4fded1
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_fail.sol
@@ -0,0 +1,42 @@
+contract Test
+{
+    function uint256_to_uint256(uint256 x) internal pure returns (uint256) { return x; }
+    function uint256_to_string(uint256 x) internal pure returns (string memory) { return x == 0 ? "a" : "b"; }
+    function uint256_to_string_storage(uint256) internal pure returns (string storage);
+    function string_to_uint256(string memory x) internal pure returns (uint256) { return bytes(x).length; }
+    function string_to_string(string memory x) internal pure returns (string memory) { return x; }
+
+    function uint256_uint256_to_uint256(uint256 x, uint256 y) internal pure returns (uint256) { return x + y; }
+    function uint256_uint256_to_string(uint256 x, uint256 y) internal pure returns (string memory) { return x == y ? "a" : "b"; }
+    function string_uint256_to_string(string memory x, uint256 y) internal pure returns (string memory) { return y == 0 ? "a" : x; }
+    function string_string_to_string(string memory x, string memory y) internal pure returns (string memory) { return bytes(x).length == 0 ? y : x; }
+    function uint256_string_to_string(uint256 x, string memory y) internal pure returns (string memory) { return x == 0 ? "a" : y; }
+
+    function tests() internal pure
+    {
+      function (uint256) internal pure returns (uint256) var_uint256_to_uint256 = uint256_to_string;
+      function (uint256) internal pure returns (string memory) var_uint256_to_string = uint256_to_string_storage;
+      function (string memory) internal pure returns (uint256) var_string_to_uint256 = uint256_to_string;
+      function (string memory) internal pure returns (string memory) var_string_to_string = var_uint256_to_string;
+
+      function (uint256, uint256) internal pure returns (uint256) var_uint256_uint256_to_uint256 = uint256_to_uint256;
+      function (string memory, uint256) internal pure returns (string memory) var_string_uint256_to_string = string_to_string;
+      function (string memory, string memory) internal pure returns (string memory) var_string_string_to_string = string_to_string;
+
+      var_uint256_to_uint256(1);
+      var_uint256_to_string(2);
+      var_string_to_uint256("a");
+      var_string_to_string("b");
+      var_uint256_uint256_to_uint256(3, 4);
+      var_string_uint256_to_string("c", 7);
+      var_string_string_to_string("d", "e");
+    }
+}
+// ----
+// TypeError: (1218-1311): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (uint256) pure returns (uint256).
+// TypeError: (1319-1425): Type function (uint256) pure returns (string storage pointer) is not implicitly convertible to expected type function (uint256) pure returns (string memory).
+// TypeError: (1433-1531): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (uint256).
+// TypeError: (1539-1646): Type function (uint256) pure returns (string memory) is not implicitly convertible to expected type function (string memory) pure returns (string memory).
+// TypeError: (1655-1766): Type function (uint256) pure returns (uint256) is not implicitly convertible to expected type function (uint256,uint256) pure returns (uint256).
+// TypeError: (1774-1893): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,uint256) pure returns (string memory).
+// TypeError: (1901-2025): Type function (string memory) pure returns (string memory) is not implicitly convertible to expected type function (string memory,string memory) pure returns (string memory).
diff --git a/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_success.sol b/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_success.sol
new file mode 100644
index 00000000..f750632e
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_types/function_parameter_return_types_success.sol
@@ -0,0 +1,39 @@
+contract Test
+{
+  function uint256_to_uint256(uint256 x) internal pure returns (uint256) { return x; }
+  function uint256_to_string(uint256 x) internal pure returns (string memory) { return x == 0 ? "a" : "b"; }
+  function string_to_uint256(string memory x) internal pure returns (uint256) { return bytes(x).length; }
+  function string_to_string(string memory x) internal pure returns (string memory) { return x; }
+
+  function uint256_uint256_to_uint256(uint256 x, uint256 y) internal pure returns (uint256) { return x + y; }
+  function uint256_uint256_to_string(uint256 x, uint256 y) internal pure returns (string memory) { return x == y ? "a" : "b"; }
+  function string_uint256_to_string(string memory x, uint256 y) internal pure returns (string memory) { return y == 0 ? "a" : x; }
+  function string_string_to_string(string memory x, string memory y) internal pure returns (string memory) { return bytes(x).length == 0 ? y : x; }
+  function uint256_string_to_string(uint256 x, string memory y) internal pure returns (string memory) { return x == 0 ? "a" : y; }
+
+  function tests() internal pure
+  {
+    function (uint256) internal pure returns (uint256) var_uint256_to_uint256 = uint256_to_uint256;
+    function (uint256) internal pure returns (string memory) var_uint256_to_string = uint256_to_string;
+    function (string memory) internal pure returns (uint256) var_string_to_uint256 = string_to_uint256;
+    function (string memory) internal pure returns (string memory) var_string_to_string = string_to_string;
+
+    function (uint256, uint256) internal pure returns (uint256) var_uint256_uint256_to_uint256 = uint256_uint256_to_uint256;
+    function (uint256, uint256) internal pure returns (string memory) var_uint256_uint256_to_string = uint256_uint256_to_string;
+    function (string memory, uint256) internal pure returns (string memory) var_string_uint256_to_string = string_uint256_to_string;
+    function (string memory, string memory) internal pure returns (string memory) var_string_string_to_string = string_string_to_string;
+    function (uint256, string memory) internal pure returns (string memory) var_uint256_string_to_string = uint256_string_to_string;
+
+    // Avoid unused variable warnings:
+    var_uint256_to_uint256(1);
+    var_uint256_to_string(2);
+    var_string_to_uint256("a");
+    var_string_to_string("b");
+    var_uint256_uint256_to_uint256(3, 4);
+    var_uint256_uint256_to_string(5, 6);
+    var_string_uint256_to_string("c", 7);
+    var_string_string_to_string("d", "e");
+    var_uint256_string_to_string(8, "f");
+  }
+}
+// ----
diff --git a/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_fail.sol b/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_fail.sol
new file mode 100644
index 00000000..818d7840
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_fail.sol
@@ -0,0 +1,51 @@
+contract Test
+{
+  function internalPureFunc(uint256 x) internal pure returns (uint256) { return x; }
+  function internalViewFunc(uint256 x) internal view returns (uint256) { return x; }
+  function internalMutableFunc(uint256 x) internal returns (uint256) { return x; }
+
+  function externalPureFunc(uint256 x) external pure returns (uint256) { return x; }
+  function externalViewFunc(uint256 x) external view returns (uint256) { return x; }
+  function externalPayableFunc(uint256 x) external payable returns (uint256) { return x; }
+  function externalMutableFunc(uint256 x) external returns (uint256) { return x; }
+
+  function funcTakesInternalPure(function(uint256) internal pure returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesInternalView(function(uint256) internal view returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesInternalMutable(function(uint256) internal returns(uint256) a) internal returns (uint256) { return a(4); }
+
+  function funcTakesExternalPure(function(uint256) external pure returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesExternalView(function(uint256) external view returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesExternalPayable(function(uint256) external payable returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesExternalMutable(function(uint256) external returns(uint256) a) internal returns (uint256) { return a(4); }
+
+  function tests() internal
+  {
+    funcTakesInternalPure(internalViewFunc); // view -> pure should fail
+    funcTakesInternalPure(internalMutableFunc); // mutable -> pure should fail
+
+    funcTakesInternalView(internalMutableFunc); // mutable -> view should fail
+
+    funcTakesExternalPure(this.externalViewFunc); // view -> pure should fail
+    funcTakesExternalPure(this.externalPayableFunc); // payable -> pure should fail
+    funcTakesExternalPure(this.externalMutableFunc); // mutable -> pure should fail
+
+    funcTakesExternalView(this.externalPayableFunc); // payable -> view should fail
+    funcTakesExternalView(this.externalMutableFunc); // mutable -> view should fail
+
+    funcTakesExternalPayable(this.externalPureFunc); // pure -> payable should fail
+    funcTakesExternalPayable(this.externalViewFunc); // view -> payable should fail
+    funcTakesExternalPayable(this.externalMutableFunc); // mutable -> payable should fail
+  }
+}
+// ----
+// TypeError: (1580-1596): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) view returns (uint256) to function (uint256) pure returns (uint256) requested.
+// TypeError: (1653-1672): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) returns (uint256) to function (uint256) pure returns (uint256) requested.
+// TypeError: (1733-1752): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) returns (uint256) to function (uint256) view returns (uint256) requested.
+// TypeError: (1813-1834): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) view external returns (uint256) to function (uint256) pure external returns (uint256) requested.
+// TypeError: (1891-1915): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) payable external returns (uint256) to function (uint256) pure external returns (uint256) requested.
+// TypeError: (1975-1999): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) external returns (uint256) to function (uint256) pure external returns (uint256) requested.
+// TypeError: (2060-2084): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) payable external returns (uint256) to function (uint256) view external returns (uint256) requested.
+// TypeError: (2144-2168): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) external returns (uint256) to function (uint256) view external returns (uint256) requested.
+// TypeError: (2232-2253): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) pure external returns (uint256) to function (uint256) payable external returns (uint256) requested.
+// TypeError: (2316-2337): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) view external returns (uint256) to function (uint256) payable external returns (uint256) requested.
+// TypeError: (2400-2424): Invalid type for argument in function call. Invalid implicit conversion from function (uint256) external returns (uint256) to function (uint256) payable external returns (uint256) requested.
diff --git a/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_success.sol b/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_success.sol
new file mode 100644
index 00000000..4ee515fc
--- /dev/null
+++ b/test/libsolidity/syntaxTests/types/function_types/function_state_mutability_success.sol
@@ -0,0 +1,46 @@
+contract Test
+{
+  uint y;
+  function internalPureFunc(uint256 x) internal pure returns (uint256) { return x; }
+  function internalViewFunc(uint256 x) internal view returns (uint256) { return x + y; }
+  function internalMutableFunc(uint256 x) internal returns (uint256) { y = x; return x; }
+
+  function externalPureFunc(uint256 x) external pure returns (uint256) { return x; }
+  function externalViewFunc(uint256 x) external view returns (uint256) { return x + y; }
+  function externalPayableFunc(uint256 x) external payable returns (uint256) { return x + y; }
+  function externalMutableFunc(uint256 x) external returns (uint256) { y = x; return x; }
+
+  function funcTakesInternalPure(function(uint256) internal pure returns(uint256) a) internal pure returns (uint256) { return a(4); }
+  function funcTakesInternalView(function(uint256) internal view returns(uint256) a) internal view returns (uint256) { return a(4); }
+  function funcTakesInternalMutable(function(uint256) internal returns(uint256) a) internal returns (uint256) { return a(4); }
+
+  function funcTakesExternalPure(function(uint256) external pure returns(uint256) a) internal pure returns (uint256) { return a(4); }
+  function funcTakesExternalView(function(uint256) external view returns(uint256) a) internal view returns (uint256) { return a(4); }
+  function funcTakesExternalPayable(function(uint256) external payable returns(uint256) a) internal returns (uint256) { return a(4); }
+  function funcTakesExternalMutable(function(uint256) external returns(uint256) a) internal returns (uint256) { return a(4); }
+
+  function tests() internal
+  {
+    funcTakesInternalPure(internalPureFunc);
+
+    funcTakesInternalView(internalPureFunc);
+    funcTakesInternalView(internalViewFunc);
+
+    funcTakesInternalMutable(internalPureFunc);
+    funcTakesInternalMutable(internalViewFunc);
+    funcTakesInternalMutable(internalMutableFunc);
+
+    funcTakesExternalPure(this.externalPureFunc);
+
+    funcTakesExternalView(this.externalPureFunc);
+    funcTakesExternalView(this.externalViewFunc);
+
+    funcTakesExternalPayable(this.externalPayableFunc);
+
+    funcTakesExternalMutable(this.externalPureFunc);
+    funcTakesExternalMutable(this.externalViewFunc);
+    funcTakesExternalMutable(this.externalPayableFunc);
+    funcTakesExternalMutable(this.externalMutableFunc);
+  }
+}
+// ----