Syntax for custom errors.

test/libsolidity/syntaxTests/errors/basic.sol

@@ -0,0 +1,6 @@
+contract C {
+    error MyError();
+    error MyError2(uint x);
+    error MyError3(uint x, bytes);
+}
+// ----

test/libsolidity/syntaxTests/errors/basic_usage.sol

@@ -0,0 +1,9 @@
+error E();
+function f() pure {
+    revert(E());
+}
+function g() pure {
+    bool x;
+    require(x, E());
+}
+// ----

test/libsolidity/syntaxTests/errors/basic_usage_params.sol

@@ -0,0 +1,9 @@
+error E(uint,string);
+function f() pure {
+    revert(E(2, "abc"));
+}
+function g(string storage s) pure {
+    bool x;
+    require(x, E(7, s));
+}
+// ----

test/libsolidity/syntaxTests/errors/basic_usage_parethesized.sol

@@ -0,0 +1,13 @@
+error E();
+function f() pure {
+    revert((E()));
+}
+function g() pure {
+    bool x;
+    require(x, (E()));
+}
+// ----
+// TypeError 6473: (43-46): Tuple component cannot be empty.
+// TypeError 4423: (42-47): Expected error or string.
+// TypeError 6473: (100-103): Tuple component cannot be empty.
+// TypeError 4423: (99-104): Expected error or string.

test/libsolidity/syntaxTests/errors/clash_function_error.sol

@@ -0,0 +1,4 @@
+function Err() pure {}
+error Err();
+// ----
+// DeclarationError 2333: (23-35): Identifier already declared.

test/libsolidity/syntaxTests/errors/clash_function_error_inheritance.sol

@@ -0,0 +1,4 @@
+contract A { function Err() public pure {} }
+contract B is A { error Err(); }
+// ----
+// DeclarationError 9097: (63-75): Identifier already declared.

test/libsolidity/syntaxTests/errors/error_reserved_name.sol

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

test/libsolidity/syntaxTests/errors/file_level.sol

@@ -0,0 +1,6 @@
+error MyError();
+error MyError2(uint x);
+contract C {
+    error MyError3(uint x, bytes);
+}
+// ----

test/libsolidity/syntaxTests/errors/name_parenthesized.sol

@@ -0,0 +1,6 @@
+error E();
+function f() pure {
+    revert((E)());
+}
+// ----
+// TypeError 4423: (42-47): Expected error or string.

test/libsolidity/syntaxTests/errors/named_error.sol

@@ -0,0 +1,5 @@
+error E(uint a);
+function f() pure {
+    revert(E({a: 2}));
+}
+// ----

test/libsolidity/syntaxTests/errors/named_require.sol

@@ -0,0 +1,6 @@
+error E();
+function f() pure {
+    require({error: E()});
+}
+// ----
+// TypeError 1886: (35-56): Named arguments cannot be used for this function call.

test/libsolidity/syntaxTests/errors/named_revert.sol

@@ -0,0 +1,6 @@
+error E();
+function f() pure {
+    revert({error: E()});
+}
+// ----
+// TypeError 1886: (35-55): Named arguments cannot be used for this function call.

test/libsolidity/syntaxTests/errors/nested_invocation.sol

@@ -0,0 +1,7 @@
+error E1();
+error E2();
+function f() pure {
+    revert(E1(E2));
+}
+// ----
+// TypeError 6160: (55-61): Wrong argument count for function call: 1 arguments given but expected 0.

test/libsolidity/syntaxTests/errors/nested_invocation2.sol

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

test/libsolidity/syntaxTests/errors/nested_invocation3.sol

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

test/libsolidity/syntaxTests/errors/nested_invocation4.sol

@@ -0,0 +1,7 @@
+error E1(uint);
+error E2();
+function f() pure {
+    revert(E1([E2()]));
+}
+// ----
+// TypeError 5604: (63-67): Array component cannot be empty.

test/libsolidity/syntaxTests/errors/no_mappings.sol

@@ -0,0 +1,9 @@
+error MyError(mapping(uint => uint));
+contract C {
+    error MyError2(mapping(uint => uint));
+}
+// ----
+// TypeError 3448: (14-35): Type containing a (nested) mapping is not allowed as error parameter type.
+// TypeError 3417: (14-35): Internal or recursive type is not allowed as error parameter type.
+// TypeError 3448: (70-91): Type containing a (nested) mapping is not allowed as error parameter type.
+// TypeError 3417: (70-91): Internal or recursive type is not allowed as error parameter type.

test/libsolidity/syntaxTests/errors/no_overloading.sol

@@ -0,0 +1,4 @@
+error Err(uint);
+error Err(bytes32);
+// ----
+// DeclarationError 2333: (17-36): Identifier already declared.

test/libsolidity/syntaxTests/errors/no_overloading_inheritance.sol

@@ -0,0 +1,8 @@
+contract A {
+    error Err(uint);
+}
+contract B is A {
+    error Err(bytes32);
+}
+// ----
+// DeclarationError 9097: (58-77): Identifier already declared.

test/libsolidity/syntaxTests/errors/no_structs_in_abiv1.sol

@@ -0,0 +1,7 @@
+pragma abicoder v1;
+struct S {uint a;}
+contract C {
+    error MyError(S);
+}
+// ----
+// TypeError 3061: (70-71): This type is only supported in ABI coder v2. Use "pragma abicoder v2;" to enable the feature.

test/libsolidity/syntaxTests/errors/panic_reserved_name.sol

@@ -0,0 +1,5 @@
+// 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.

test/libsolidity/syntaxTests/errors/struct_named_error.sol

@@ -0,0 +1,6 @@
+// Test that the parser workaround is not breaking.
+struct error {uint a;}
+contract C {
+    error x;
+}
+// ----

test/libsolidity/syntaxTests/errors/usage_standalone.sol

@@ -0,0 +1,6 @@
+error E();
+function f() pure {
+    E();
+}
+// ----
+// TypeError 7757: (35-38): Errors can only be created directly inside require or revert calls.

test/libsolidity/syntaxTests/errors/usage_standalone_no_call.sol

@@ -0,0 +1,7 @@
+error E();
+function f() pure {
+    // TODO is it a problem that we do not get an error here?
+    // we should at least get "statement has no effect"
+    E;
+}
+// ----

test/libsolidity/syntaxTests/errors/usage_with_options.sol

@@ -0,0 +1,6 @@
+error E1();
+function f() pure {
+    revert(E1{gas: 10}());
+}
+// ----
+// TypeError 2193: (43-54): Function call options can only be set on external function calls or contract creations.

test/libsolidity/syntaxTests/errors/use_without_parentheses.sol

@@ -0,0 +1,7 @@
+error E1();
+error E2();
+function f() pure {
+    revert(E1);
+}
+// ----
+// TypeError 4423: (55-57): Expected error or string.

test/libsolidity/syntaxTests/errors/using_structs.sol

@@ -0,0 +1,6 @@
+struct S {uint a;}
+contract C {
+    error MyError(S);
+    error MyError2(S t);
+}
+// ----

test/libsolidity/syntaxTests/errors/wrong_arguments.sol

@@ -0,0 +1,6 @@
+error E(uint,string);
+function f() pure {
+    revert(E(2, 3));
+}
+// ----
+// TypeError 9553: (58-59): Invalid type for argument in function call. Invalid implicit conversion from int_const 3 to string memory requested.

test/libsolidity/syntaxTests/errors/wrong_number_of_arguments.sol

@@ -0,0 +1,10 @@
+error E();
+function f() pure {
+    require();
+    require(true, E(), 8);
+    revert(E(), 3);
+}
+// ----
+// TypeError 7445: (35-44): Function "require" needs 1 or 2 arguments, but provided 0.
+// TypeError 7445: (50-71): Function "require" needs 1 or 2 arguments, but provided 3.
+// TypeError 7445: (77-91): Function "revert" needs 0 or 1 arguments, but provided 2.

test/libsolidity/syntaxTests/nameAndTypeResolution/428_bare_revert.sol

@@ -5,4 +5,4 @@ contract C {
     }
 }
 // ----
-// TypeError 2144: (81-87): No matching declaration found after variable lookup.
+// Warning 6133: (81-87): Statement has no effect.

test/libsolidity/syntaxTests/nameAndTypeResolution/432_bare_require.sol

@@ -3,4 +3,4 @@ contract C {
     function f() pure public { require; }
 }
 // ----
-// TypeError 2144: (101-108): No matching declaration found after variable lookup.
+// Warning 6133: (101-108): Statement has no effect.

test/libsolidity/syntaxTests/tupleAssignments/empty_tuples_lhs.sol

@@ -26,4 +26,4 @@ contract C {
 // TypeError 5547: (401-404): Empty tuple on the left hand side.
 // TypeError 4289: (399-466): Compound assignment is not allowed for tuple types.
 // TypeError 7407: (410-466): Type bytes32 is not implicitly convertible to expected type tuple().
-// TypeError 9322: (389-396): No matching declaration found after argument-dependent lookup.
+// TypeError 2956: (399-466): Invalid type for argument in function call. Invalid implicit conversion from tuple() to bool requested.