fixup! Syntax changes for catching custom errors.

libsolidity/analysis/TypeChecker.cpp

@@ -1007,7 +1007,7 @@ void TypeChecker::endVisit(TryStatement const& _tryStatement)
 					"This try statement already has a low-level catch clause."
 				);
 			lowLevelClause = &clause;
-			if (clause.parameters() && !clause.parameters()->parameters().empty())
+			if (clause.parameters())
 			{
 				if (
 					clause.parameters()->parameters().size() != 1 ||
@@ -1072,7 +1072,6 @@ void TypeChecker::endVisit(TryStatement const& _tryStatement)
 		else
 		{
 			solAssert(clause.kind() == TryCatchClause::Kind::UserDefined, "");
-			solAssert(*clause.errorName().annotation().requiredLookup == VirtualLookup::Static, "");
 			ErrorDefinition const* error = dynamic_cast<ErrorDefinition const*>(clause.errorName().annotation().referencedDeclaration);
 			if (!error)
 			{
@@ -1091,16 +1090,20 @@ void TypeChecker::endVisit(TryStatement const& _tryStatement)
 				!clause.parameters() ||
 				clause.parameters()->parameters().size() != error->parameters().size()
 			)
-				m_errorReporter.typeError(1271_error, clause.location(), "Expected `catch Panic(uint ...) { ... }`.");
-			else
-				for (auto&& [varDecl, parameter]: ranges::views::zip(clause.parameters()->parameters(), error->parameters()))
-					if (*varDecl->type() != *parameter->type())
-						m_errorReporter.typeError(
-							63958_error,
-							varDecl->location(),
-							("Expected a parameter of type \"" + parameter->type()->toString(true) + "\" ") +
-							("but got \"" + varDecl->type()->toString(true) + "\"")
-						);
+				m_errorReporter.typeError(
+					4873_error,
+					clause.location(),
+					("Expected " + to_string(error->parameters().size()) + " parameters for error \"") +
+					(error->name() + "\" but got " + to_string(clause.parameters()->parameters().size()) + ".")
+				);
+			for (auto&& [varDecl, parameter]: ranges::views::zip(clause.parameters()->parameters(), error->parameters()))
+				if (*varDecl->type() != *parameter->type())
+					m_errorReporter.typeError(
+						63958_error,
+						varDecl->location(),
+						("Expected a parameter of type \"" + parameter->type()->toString(true) + "\" ") +
+						("but got \"" + varDecl->type()->toString(true) + "\"")
+					);
 		}
 	}
 }

test/libsolidity/syntaxTests/tryCatch/catch_custom.sol

@@ -0,0 +1,14 @@
+contract C {
+    error E();
+    function f() public {
+        try this.f() {
+
+        } catch E() {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// UnimplementedFeatureError: NONE

test/libsolidity/syntaxTests/tryCatch/catch_custom_alias_error.sol

@@ -0,0 +1,18 @@
+==== Source: A ====
+error E(uint);
+==== Source: B ====
+import {E as Error} from "A";
+
+contract C {
+    function f() public {
+        try this.f() {
+
+        } catch Error(uint x) {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// TypeError 2943: (B:104-136): Expected `catch Error(string memory ...) { ... }`.

test/libsolidity/syntaxTests/tryCatch/catch_custom_involving_reserved.sol

@@ -0,0 +1,18 @@
+==== Source: A ====
+error E(uint);
+==== Source: B ====
+import "A" as Error;
+
+contract C {
+    function f() public {
+        try this.f() {
+
+        } catch Error.E(uint x) {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// ParserError 2314: (B:106-107): Expected '(' but got '.'

test/libsolidity/syntaxTests/tryCatch/catch_custom_no_paren.sol

@@ -0,0 +1,14 @@
+contract C {
+    error E();
+    function f() public returns (uint, uint) {
+        try this.f() {
+
+        } catch E {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// ParserError 2314: (117-118): Expected '(' but got '{'

test/libsolidity/syntaxTests/tryCatch/catch_custom_path.sol

@@ -0,0 +1,19 @@
+==== Source: A ====
+error E(uint);
+==== Source: B ====
+import "A" as X;
+
+contract C {
+    function f() public {
+        try this.f() {
+
+        } catch X.E(uint x) {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// UnimplementedFeatureError: NONE
+// Warning 5667: (B:101-107): Unused try/catch parameter. Remove or comment out the variable name to silence this warning.

test/libsolidity/syntaxTests/tryCatch/catch_custom_too_little.sol

@@ -0,0 +1,14 @@
+contract C {
+    error E(uint x);
+    function f() public returns (uint, uint) {
+        try this.f() {
+
+        } catch E() {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// TypeError 4873: (115-137): Expected 1 parameters for error "E" but got 0.

test/libsolidity/syntaxTests/tryCatch/catch_custom_too_many.sol

@@ -0,0 +1,14 @@
+contract C {
+    error E();
+    function f() public returns (uint, uint) {
+        try this.f() {
+
+        } catch E(uint a) {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// TypeError 4873: (109-137): Expected 0 parameters for error "E" but got 1.

test/libsolidity/syntaxTests/tryCatch/catch_custom_wrong_type.sol

@@ -0,0 +1,15 @@
+contract C {
+    error E(uint a, uint8 b);
+    function f() public returns (uint, uint) {
+        try this.f() {
+
+        } catch E(uint8 x, uint y) {
+
+        }
+    }
+}
+// ====
+// EVMVersion: >=byzantium
+// ----
+// TypeError 63958: (132-139): Expected a parameter of type "uint256" but got "uint8"
+// TypeError 63958: (141-147): Expected a parameter of type "uint8" but got "uint256"

test/libsolidity/syntaxTests/tryCatch/empty_catch.sol

@@ -8,4 +8,4 @@ contract C {
     }
 }
 // ----
-// ParserError 3546: (101-102): Expected type name
+// TypeError 6231: (94-115): Expected `catch (bytes memory ...) { ... }` or `catch { ... }`.