fixup! Syntax changes for catching custom errors.

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 { ... }`.