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import pyparsing as pp
import pytest
from examples.tiny.tiny_parser import parse_tiny
def test_parse_assign_read_write_in_main():
src = "int main(){ read x; y := 42; write y; return 0; }"
res = parse_tiny(src)
assert "program" in res
main = res.program.main
stmts = main.body.stmts
assert len(stmts) == 4
assert stmts[0].type == "read_stmt"
assert stmts[1].type == "assign_stmt"
assert stmts[1].target == "y"
assert stmts[2].type == "write_stmt"
assert stmts[3].type == "return_stmt"
def test_parse_if_then_elseif_else():
src = (
"int main(){ if x < 10 then y := y + 1; write y; elseif x = 0 then write 0; else read x; end return 0; }"
)
res = parse_tiny(src)
ifres = res.program.main.body.stmts[0]
assert ifres.type == "if_stmt"
assert hasattr(ifres, "cond")
assert len(ifres.then) == 2
# optional elseif list
assert "elseif" in ifres
# else block exists with 1 statement
assert len(ifres["else"]) == 1
def test_repeat_until_with_c_style_comment():
src = "int main(){ repeat /*loop*/ x := x - 1; write x; until x = 0 return 0; }"
res = parse_tiny(src)
rpt = res.program.main.body.stmts[0]
assert rpt.type == "repeat_stmt"
assert len(rpt.body) == 2
# condition contains a relop; infix_notation flattens to [lhs, op, rhs]
assert rpt.cond[1] == "="
def test_parse_all_required():
# extra trailing garbage should fail when parse_all=True
with pytest.raises(pp.ParseException):
parse_tiny("int main(){ read x; return 0; } $$$")
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