def test_other_instance_field_access():
ast = project_10.parse_class("""
class BoxedInt {
field int value;
method boolean compare(BoxedInt other) {
return value < other.value;
}
}
""")
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert asm.lines == [
" function BoxedInt.compare 1",
" push argument 0",
" pop pointer 0",
" push this 0",
" push argument 1",
" pop pointer 1",
" push that 0",
" lt",
" return",
"",
]
def test_program_seven_opcodes():
"""This program is so simple that there's probably only one reasonable way to compile it,
so just compare the VM opcodes."""
with open("examples/project_11/Seven/Main.jack") as f:
src = f.read()
ast = project_10.parse_class(src)
asm = AssemblySource()
project_11.compile_class(ast, asm)
expected = """
function Main.main 1
push constant 1
push constant 2
push constant 3
call Math.multiply 2
add
call Output.printInt 1
pop temp 0
push constant 0
return
"""
assert list(asm.lines) == expected.split("\n")[1:-1]
def test_missing_return():
"""Another very common error."""
ast = project_10.parse_class("""
class Foo {
function void noReturn() {
// oops, forgot to `return;` here
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == ('Missing "return" in Foo.noReturn', )
def test_no_this():
"""This could be confusing, so make it an error."""
ast = project_10.parse_class("""
class Foo {
function void run() {
return this;
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Undefined "this" in static context: function Foo.run', )
def test_constructor_void_return():
"""Constructor must return "this", or the caller will be surprised."""
ast = project_10.parse_class("""
class Foo {
constructor Foo new() {
return; // meaning "null"
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Does not return "this": constructor Foo.new', )
def test_constructor_bad_result_type():
"""This could be confusing, so make it an error."""
ast = project_10.parse_class("""
class Foo {
constructor Bar new() {
return this;
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Result type does not match: constructor Foo.new', )
def test_constructor_wrong_name():
"""This could be confusing, so make it an error."""
ast = project_10.parse_class("""
class Foo {
constructor Foo notNew() {
return this;
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Must be named "new": constructor Foo.notNew', )
def test_call_method_from_function_context():
"""A common error case; referring to a function using the method-call syntax."""
ast = project_10.parse_class("""
class Foo {
function void run() {
do go(); // Probably meant `Foo.go()`
return;
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Tried to use implicit "this" in static (function) context: Foo.run', )
def test_return_on_both_branches():
"""Accept this common pattern."""
ast = project_10.parse_class("""
class Foo {
function void toInt(boolean x) {
if (x) {
return 1;
}
else {
return 0;
}
}
}
""")
asm = AssemblySource()
project_11.compile_class(ast, asm)
def test_field_in_function_context():
"""A common error case; referring to an instance member within a function."""
ast = project_10.parse_class("""
class Foo {
field int x;
function int run() {
return x;
}
}
""")
with pytest.raises(Exception) as exc_info:
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert exc_info.value.args == (
'Tried to use field "x" in static context: function Foo.run', )
def test_call_function_from_function_context():
ast = project_10.parse_class("""
class Foo {
function void run() {
do Bar.go();
return;
}
}
""")
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert asm.lines == [
" function Foo.run 1",
" call Bar.go 0",
" pop temp 0",
" push constant 0",
" return",
"",
]
def test_call_method_from_method_context():
ast = project_10.parse_class("""
class Foo {
method void run() {
do go();
return;
}
}
""")
asm = AssemblySource()
project_11.compile_class(ast, asm)
assert asm.lines == [
" function Foo.run 1",
" push argument 0",
" pop pointer 0",
" push pointer 0", # implicit `this` for self call
" call Foo.go 1",
" pop temp 0",
" push constant 0",
" return",
"",
]
def test_parse_array_test():
ast = project_10.parse_class(ARRAY_TEST)
print(ast)
expected = Class("Main", [], [
SubroutineDec(
"function",
None,
"main",
[],
SubroutineBody([
VarDec(Type("Array"), ["a"]),
VarDec(Type("int"), ["length"]),
VarDec(Type("int"), ["i", "sum"]),
], [
LetStatement(
"length", None,
SubroutineCall(class_name="Keyboard",
var_name=None,
sub_name="readInt",
args=[StringConstant("HOW MANY NUMBERS? ")
])),
LetStatement(
"a", None,
SubroutineCall(class_name="Array",
var_name=None,
sub_name="new",
args=[VarRef("length")])),
LetStatement("i", None, IntegerConstant(0)),
WhileStatement(
BinaryExpression(VarRef("i"), Op("<"), VarRef("length")), [
LetStatement(
"a", VarRef("i"),
SubroutineCall(
class_name="Keyboard",
var_name=None,
sub_name="readInt",
args=[
StringConstant("ENTER THE NEXT NUMBER: ")
])),
LetStatement(
"i", None,
BinaryExpression(VarRef("i"), Op("+"),
IntegerConstant(1))),
]),
LetStatement("i", None, IntegerConstant(0)),
LetStatement("sum", None, IntegerConstant(0)),
WhileStatement(
BinaryExpression(VarRef("i"), Op("<"), VarRef("length")), [
LetStatement(
"sum", None,
BinaryExpression(VarRef("sum"), Op("+"),
ArrayRef("a", VarRef("i")))),
LetStatement(
"i", None,
BinaryExpression(VarRef("i"), Op("+"),
IntegerConstant(1))),
]),
DoStatement(
SubroutineCall(class_name="Output",
var_name=None,
sub_name="printString",
args=[StringConstant("THE AVERAGE IS: ")])),
DoStatement(
SubroutineCall(class_name="Output",
var_name=None,
sub_name="printInt",
args=[
BinaryExpression(
VarRef("sum"), Op("/"),
VarRef("length"))
])),
DoStatement(expr=SubroutineCall(class_name="Output",
var_name=None,
sub_name="println",
args=[])),
ReturnStatement(expr=None),
]),
),
])
assert ast == expected