public void Parse_BinaryExpression_HonorsPrecedences(SyntaxKind op1, SyntaxKind op2)
{
//Arrange
var op1Precedence = SyntaxFacts.GetBinaryOperatorPrecedence(op1);
var op2Precedence = SyntaxFacts.GetBinaryOperatorPrecedence(op2);
var op1Text = SyntaxFacts.GetText(op1);
var op2Text = SyntaxFacts.GetText(op2);
var text = $"a {op1Text} b {op2Text} c";
var expression = ParseExpression(text);
if (op1Precedence >= op2Precedence)
{
/*
* op2
* / \
* op1 c
* / \
* a b
*/
using (var e = new AssertingEnumerator(expression))
{
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "a");
e.AssertToken(op1, op1Text);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "b");
e.AssertToken(op2, op2Text);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "c");
}
}
else
{
/*
* op1
* / \
* a op2
* / \
* b c
*/
using (var e = new AssertingEnumerator(expression))
{
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "a");
e.AssertToken(op1, op1Text);
e.AssertNode(SyntaxKind.BinaryExpression);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "b");
e.AssertToken(op2, op2Text);
e.AssertNode(SyntaxKind.NameExpression);
e.AssertToken(SyntaxKind.IdentifierToken, "c");
}
}
}
public void Parse_UnaryExpression_HonorsPrecedences(SyntaxKind unaryKind, SyntaxKind binaryKind)
{
//Arrange
var unaryPrecedence = SyntaxFacts.GetUnaryOperatorPrecedence(unaryKind);
var binaryPrecedence = SyntaxFacts.GetBinaryOperatorPrecedence(binaryKind);
var unaryText = SyntaxFacts.GetText(unaryKind);
var binaryText = SyntaxFacts.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");
}
}
}