def test_precedence(self):
buf = """
fn prec() -> int {
2 + 3 * 2 + 2 / 8;
}
"""
exprs = [
ast.Function(
"prec",
[],
[
ast.ExprStatement(
ast.BinaryOp(
ast.BinaryOp(
ast.Number(2),
ast.BinaryOp(ast.Number(3), ast.Number(2),
Token(TokenType.MULTIPLY, "*")),
Token(TokenType.ADD, "+"),
),
ast.BinaryOp(ast.Number(2), ast.Number(8),
Token(TokenType.DIVIDE, "/")),
Token(TokenType.ADD, "+"),
))
],
ast.Type(ast.TypeKind.INT),
)
]
self._test_parse_impl(buf, exprs)
def test_while_loop(self):
buf = """
fn loopTest(int x) -> int {
while (x < 5) {
print("blah");
}
return 0;
}
"""
exprs = [
ast.Function(
"loopTest",
[("x", ast.Type(ast.TypeKind.INT))],
[
ast.WhileLoop(
ast.BinaryOp(ast.VariableRef("x"), ast.Number(5),
Token(TokenType.LESS_THAN, "<")),
[
ast.ExprStatement(
ast.FunctionCall("print",
[ast.String("blah")]))
],
),
ast.ReturnStatement(ast.Number(0)),
],
ast.Type(ast.TypeKind.INT),
)
]
self._test_parse_impl(buf, exprs)
def test_if_statements(self):
buf = """
fn foo() -> string {
if (3 == 3) {
return "foo";
}
return "bar";
}
"""
exprs = [
ast.Function(
"foo",
[],
[
ast.IfStatement(
ast.BinaryOp(ast.Number(3), ast.Number(3),
Token(TokenType.EQUALS, "==")),
[ast.ReturnStatement(ast.String("foo"))],
list(),
),
ast.ReturnStatement(ast.String("bar")),
],
ast.Type(ast.TypeKind.STRING),
)
]
self._test_parse_impl(buf, exprs)
def _parse_multiplication(self):
lhs = self._parse_postfix()
while True:
tok = self.cur_tok
if self._consume_token(TokenType.MULTIPLY) or self._consume_token(TokenType.DIVIDE):
lhs = ast.BinaryOp(lhs, self._parse_primary_expr(), tok)
else:
return lhs
def _parse_addition(self):
lhs = self._parse_multiplication()
while True:
tok = self.cur_tok
if self._consume_token(TokenType.ADD) or self._consume_token(TokenType.SUBTRACT):
lhs = ast.BinaryOp(lhs, self._parse_multiplication(), tok)
else:
return lhs
def _parse_equality(self):
lhs = self._parse_relational()
while True:
tok = self.cur_tok
if self._consume_token(TokenType.EQUALS) or self._consume_token(TokenType.NOT_EQUALS):
lhs = ast.BinaryOp(lhs, self._parse_relational(), tok)
else:
return lhs
def _parse_assignment(self):
lhs = self._parse_equality()
while True:
tok = self.cur_tok
if self._consume_token(TokenType.ASSIGN):
lhs = ast.BinaryOp(lhs, self._parse_equality(), tok)
else:
return lhs
def _parse_relational(self):
lhs = self._parse_addition()
while True:
tok = self.cur_tok
if (
self._consume_token(TokenType.LESS_THAN)
or self._consume_token(TokenType.LESS_THAN_EQ)
or self._consume_token(TokenType.GREATER_THAN)
or self._consume_token(TokenType.GREATER_THAN_EQ)
):
lhs = ast.BinaryOp(lhs, self._parse_addition(), tok)
else:
return lhs