Tests for error syntax.

test/libsolidity/syntaxTests/errors/abi_decode_error.sol

@@ -0,0 +1,9 @@
+error E(uint);
+contract C {
+    function f() public pure returns (bytes memory) {
+        return abi.decode(msg.data, (E));
+    }
+}
+// ----
+// TypeError 1039: (119-120): Argument has to be a type name.
+// TypeError 5132: (90-122): Different number of arguments in return statement than in returns declaration.

test/libsolidity/syntaxTests/errors/abi_encode_error.sol

@@ -0,0 +1,8 @@
+error E(uint);
+contract C {
+    function f() public pure returns (bytes memory) {
+        return abi.encode(E);
+    }
+}
+// ----
+// TypeError 2056: (108-109): This type cannot be encoded.

test/libsolidity/syntaxTests/errors/abi_encode_error_instance.sol

@@ -0,0 +1,8 @@
+error E(uint);
+contract C {
+    function f() public pure returns (bytes memory) {
+        return abi.encode(E(2));
+    }
+}
+// ----
+// TypeError 2056: (108-112): This type cannot be encoded.

test/libsolidity/syntaxTests/errors/assert_with_cond_and_error.sol

@@ -0,0 +1,6 @@
+error E();
+function f(bool x) pure {
+    assert(x, E());
+}
+// ----
+// TypeError 6160: (41-55): Wrong argument count for function call: 2 arguments given but expected 1.

test/libsolidity/syntaxTests/errors/assert_with_error.sol

@@ -0,0 +1,6 @@
+error E();
+function f() pure {
+    assert(E());
+}
+// ----
+// TypeError 9553: (42-45): Invalid type for argument in function call. Invalid implicit conversion from tuple() to bool requested.

test/libsolidity/syntaxTests/errors/basic_usage_parethesized.sol

@@ -8,6 +8,6 @@ function g() pure {
 }
 // ----
 // TypeError 6473: (43-46): Tuple component cannot be empty.
-// TypeError 4423: (42-47): Expected error or string.
+// TypeError 4423: (42-47): Expected error instance or string.
 // TypeError 6473: (100-103): Tuple component cannot be empty.
-// TypeError 4423: (99-104): Expected error or string.
+// TypeError 4423: (99-104): Expected error instance or string.

test/libsolidity/syntaxTests/errors/error_address_payable.sol

@@ -0,0 +1,2 @@
+error E(address payable x);
+// ----

test/libsolidity/syntaxTests/errors/error_as_function_param.sol

@@ -0,0 +1,4 @@
+error E(uint);
+function f(E x) pure returns (uint) {}
+// ----
+// TypeError 5172: (26-27): Name has to refer to a struct, enum or contract.

test/libsolidity/syntaxTests/errors/error_in_interface.sol

@@ -0,0 +1,4 @@
+interface C {
+    error E(uint);
+}
+// ----

test/libsolidity/syntaxTests/errors/error_in_library.sol

@@ -0,0 +1,4 @@
+library L {
+    error E(uint);
+}
+// ----

test/libsolidity/syntaxTests/errors/error_location_memory.sol

@@ -0,0 +1,3 @@
+error E(uint[] memory);
+// ----
+// ParserError 2314: (15-21): Expected ',' but got 'memory'

test/libsolidity/syntaxTests/errors/error_location_specifier.sol

@@ -0,0 +1,3 @@
+error E(uint[] calldata);
+// ----
+// ParserError 2314: (15-23): Expected ',' but got 'calldata'

test/libsolidity/syntaxTests/errors/error_reserved_name.sol

@@ -1,3 +1,3 @@
 error Error(uint);
 // ----
-// SyntaxError 1855: (44-62): The built-in errors "Error" and "Panic" cannot be re-defined.
+// SyntaxError 1855: (0-18): The built-in errors "Error" and "Panic" cannot be re-defined.

test/libsolidity/syntaxTests/errors/hash_collision.sol

@@ -0,0 +1,6 @@
+contract test {
+    error gsf();
+    error tgeo();
+}
+// ----
+// TypeError 4883: (0-52): Error signature hash collision for tgeo()

test/libsolidity/syntaxTests/errors/indexed_error.sol

@@ -0,0 +1,3 @@
+error E(uint indexed);
+// ----
+// ParserError 2314: (13-20): Expected ',' but got 'indexed'

test/libsolidity/syntaxTests/errors/name_parenthesized.sol

@@ -3,4 +3,4 @@ function f() pure {
     revert((E)());
 }
 // ----
-// TypeError 4423: (42-47): Expected error or string.
+// TypeError 4423: (42-47): Expected error instance or string.

test/libsolidity/syntaxTests/errors/nested_invocation3.sol

@@ -1,7 +1,7 @@
-error E1(uint);
+error E1();
 error E2();
 function f() pure {
-    revert(E1(E2));
+    revert(E1(E2()));
 }
 // ----
-// TypeError 9553: (62-64): Invalid type for argument in function call. Invalid implicit conversion from function () pure to uint256 requested.
+// TypeError 6160: (55-63): Wrong argument count for function call: 1 arguments given but expected 0.

test/libsolidity/syntaxTests/errors/panic_reserved_name.sol

@@ -1,5 +1,3 @@
-// TODO: What if an error is imported and alias as Panic?
-// TODO I Think the best way would be to have Error in the global scope.
 error Panic(bytes2);
 // ----
-// SyntaxError 1855: (131-151): The built-in errors "Error" and "Panic" cannot be re-defined.
+// SyntaxError 1855: (0-20): The built-in errors "Error" and "Panic" cannot be re-defined.

test/libsolidity/syntaxTests/errors/use_without_parentheses.sol

@@ -4,4 +4,4 @@ function f() pure {
     revert(E1);
 }
 // ----
-// TypeError 4423: (55-57): Expected error or string.
+// TypeError 4423: (55-57): Expected error instance or string. Did you forget the "()" after the error?

test/libsolidity/syntaxTests/errors/weird1.sol

@@ -0,0 +1,7 @@
+error E();
+
+contract C {
+    function() internal pure x = E;
+}
+// ----
+// TypeError 7407: (58-59): Type function () pure is not implicitly convertible to expected type function () pure. Special functions can not be converted to function types.

test/libsolidity/syntaxTests/errors/weird2.sol

@@ -0,0 +1,7 @@
+error E();
+
+contract C {
+    bytes4 t = E.selector;
+}
+// ----
+// TypeError 9582: (40-50): Member "selector" not found or not visible after argument-dependent lookup in function () pure.

test/libsolidity/syntaxTests/errors/weird3.sol

@@ -0,0 +1,7 @@
+error E();
+
+contract C {
+    E x;
+}
+// ----
+// TypeError 5172: (29-30): Name has to refer to a struct, enum or contract.

test/libsolidity/syntaxTests/errors/weird4.sol

@@ -0,0 +1,9 @@
+error E();
+
+contract C {
+    function f() public pure {
+        E x;
+    }
+}
+// ----
+// TypeError 5172: (64-65): Name has to refer to a struct, enum or contract.