public void Parser_UnaryExpression_HonorsPrecedence(SyntaxKind unaryKind, SyntaxKind binaryKind)
{
var unaryPrecedence = SyntaxRules.GetUnaryOperatorPrecedence(unaryKind);
var binaryPrecedence = SyntaxRules.GetBinaryOperatorPrecedence(binaryKind);
var unaryText = SyntaxRules.GetText(unaryKind);
var binaryText = SyntaxRules.GetText(binaryKind);
var text = $"{unaryText} a {binaryText} b";
var expression = ParseExpression(text);
if (unaryPrecedence <= binaryPrecedence)
{
// binary
// / \
// unary b
// |
// a
using (var e = new AssertingEnumerator(expression))
{
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.UnaryExpression);
e.AssertToken(unaryKind, unaryText);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "a");
e.AssertToken(binaryKind, binaryText);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "b");
}
}
else
{
// unary
// |
// binary
// / \
// a b
using (var e = new AssertingEnumerator(expression))
{
e.AssertNode(SyntaxKind.UnaryExpression);
e.AssertToken(unaryKind, unaryText);
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "a");
e.AssertToken(binaryKind, binaryText);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "b");
}
}
}
