[Switch Expressions] Poor quality diagnostics

[srikanth-sankaran]

This program generates two errors:

• Syntax error, insert ";" to complete LocalVariableDeclarationStatement
• Syntax error on token "yield", AssignmentOperator expected after this token

public class X {
	public static void main(String[] args) {
		Object x = "Hello";
		String j = switch (x) {
		case String s : yield "String";
		default : { System.out.println();
			yield "Default";
		}
		}
	}
}

The second one is not helpful and head scratch inducing.

(2) This program generates: C cannot be resolved or is not a field which is not quite the case even though the error is valid.

public class X {
	enum E1 {
		A;
	}
	
	enum E2 {
		B;
	}
	
	public static final int C = 42;
	
	public static void main(String[] args) {
	
	}
	void foo(E1 e1) {
		switch (e1) {
		case A :
		case C : 	
		}
		
		System.out.println(C);
	}
}

[srikanth-sankaran]

jaavc simply says "X.java:9: error: ';' expected"