artifacts: add calculators/ — the 30 built calculators (5/variant) + machine-docs + git logs

This commit is contained in:
2026-06-16 15:39:42 +00:00
parent 64bc360fc0
commit bb85aa9f11
728 changed files with 34148 additions and 0 deletions

View File

@ -0,0 +1,34 @@
"""Evaluator: walks the AST produced by calc.parser and returns a numeric result."""
from __future__ import annotations
from .parser import Num, BinOp, Unary
class EvalError(Exception):
pass
def evaluate(node) -> int | float:
"""Recursively evaluate an AST node and return int or float."""
if isinstance(node, Num):
return node.value
if isinstance(node, Unary):
operand = evaluate(node.operand)
if node.op == "-":
return -operand
raise EvalError(f"unknown unary op: {node.op!r}")
if isinstance(node, BinOp):
left = evaluate(node.left)
right = evaluate(node.right)
if node.op == "+":
return left + right
if node.op == "-":
return left - right
if node.op == "*":
return left * right
if node.op == "/":
if right == 0:
raise EvalError("division by zero")
return left / right
raise EvalError(f"unknown binary op: {node.op!r}")
raise EvalError(f"unknown node type: {type(node).__name__!r}")

View File

@ -0,0 +1,58 @@
"""Lexer for arithmetic expressions."""
from __future__ import annotations
import re
class LexError(Exception):
pass
class Token:
__slots__ = ("kind", "value")
def __init__(self, kind: str, value):
self.kind = kind
self.value = value
def __repr__(self):
return f"Token({self.kind!r}, {self.value!r})"
def __eq__(self, other):
return isinstance(other, Token) and self.kind == other.kind and self.value == other.value
_NUMBER_RE = re.compile(r"\d+\.?\d*|\.\d+")
_SINGLE = {
"+": "PLUS",
"-": "MINUS",
"*": "STAR",
"/": "SLASH",
"(": "LPAREN",
")": "RPAREN",
}
def tokenize(src: str) -> list[Token]:
tokens: list[Token] = []
i = 0
while i < len(src):
ch = src[i]
if ch in " \t":
i += 1
continue
if ch in _SINGLE:
tokens.append(Token(_SINGLE[ch], ch))
i += 1
continue
m = _NUMBER_RE.match(src, i)
if m:
raw = m.group()
value = float(raw) if "." in raw else int(raw)
tokens.append(Token("NUMBER", value))
i = m.end()
continue
raise LexError(f"unexpected character {ch!r} at position {i}")
tokens.append(Token("EOF", None))
return tokens

View File

@ -0,0 +1,141 @@
"""Recursive-descent parser for arithmetic expressions.
Grammar (precedence low → high):
expr = term ( ('+' | '-') term )*
term = unary ( ('*' | '/') unary )*
unary = '-' unary | primary
primary = NUMBER | '(' expr ')'
AST nodes (stable shape for the evaluator):
Num(value) numeric literal; value is int or float
BinOp(op, left, right) op is one of '+', '-', '*', '/'
Unary(op, operand) op is '-'
"""
from __future__ import annotations
from typing import List
from .lexer import Token
class ParseError(Exception):
pass
class Num:
__slots__ = ("value",)
def __init__(self, value):
self.value = value
def __repr__(self):
return f"Num({self.value!r})"
def __eq__(self, other):
return isinstance(other, Num) and self.value == other.value
class BinOp:
__slots__ = ("op", "left", "right")
def __init__(self, op: str, left, right):
self.op = op
self.left = left
self.right = right
def __repr__(self):
return f"BinOp({self.op!r}, {self.left!r}, {self.right!r})"
def __eq__(self, other):
return (
isinstance(other, BinOp)
and self.op == other.op
and self.left == other.left
and self.right == other.right
)
class Unary:
__slots__ = ("op", "operand")
def __init__(self, op: str, operand):
self.op = op
self.operand = operand
def __repr__(self):
return f"Unary({self.op!r}, {self.operand!r})"
def __eq__(self, other):
return (
isinstance(other, Unary)
and self.op == other.op
and self.operand == other.operand
)
class _Parser:
def __init__(self, tokens: List[Token]):
self._tokens = tokens
self._pos = 0
def _peek(self) -> Token:
return self._tokens[self._pos]
def _consume(self) -> Token:
tok = self._tokens[self._pos]
self._pos += 1
return tok
def _expect(self, kind: str) -> Token:
tok = self._peek()
if tok.kind != kind:
raise ParseError(f"expected {kind}, got {tok.kind!r} ({tok.value!r})")
return self._consume()
def parse(self):
if self._peek().kind == "EOF":
raise ParseError("empty input")
node = self._expr()
if self._peek().kind != "EOF":
tok = self._peek()
raise ParseError(f"unexpected token {tok.kind!r} ({tok.value!r})")
return node
def _expr(self):
node = self._term()
while self._peek().kind in ("PLUS", "MINUS"):
op = self._consume().value
right = self._term()
node = BinOp(op, node, right)
return node
def _term(self):
node = self._unary()
while self._peek().kind in ("STAR", "SLASH"):
op = self._consume().value
right = self._unary()
node = BinOp(op, node, right)
return node
def _unary(self):
if self._peek().kind == "MINUS":
op = self._consume().value
operand = self._unary()
return Unary(op, operand)
return self._primary()
def _primary(self):
tok = self._peek()
if tok.kind == "NUMBER":
self._consume()
return Num(tok.value)
if tok.kind == "LPAREN":
self._consume()
node = self._expr()
self._expect("RPAREN")
return node
raise ParseError(f"unexpected token {tok.kind!r} ({tok.value!r})")
def parse(tokens: List[Token]):
"""Parse a token list produced by calc.lexer.tokenize and return an AST root node."""
return _Parser(tokens).parse()

View File

@ -0,0 +1,124 @@
"""Tests for calc.evaluator (D1D3) and CLI (D4)."""
import subprocess
import sys
import unittest
from calc.lexer import tokenize
from calc.parser import parse
from calc.evaluator import evaluate, EvalError
def ev(s):
return evaluate(parse(tokenize(s)))
class D1Arithmetic(unittest.TestCase):
def test_add_mul_precedence(self):
self.assertEqual(ev("2+3*4"), 14)
def test_paren_override_precedence(self):
self.assertEqual(ev("(2+3)*4"), 20)
def test_left_associative_sub(self):
self.assertEqual(ev("8-3-2"), 3)
def test_unary_minus_add(self):
self.assertEqual(ev("-2+5"), 3)
def test_mul_unary_minus(self):
self.assertEqual(ev("2*-3"), -6)
def test_simple_add(self):
self.assertEqual(ev("1+2"), 3)
def test_simple_sub(self):
self.assertEqual(ev("10-4"), 6)
def test_double_unary(self):
self.assertEqual(ev("--3"), 3)
class D2Division(unittest.TestCase):
def test_true_division(self):
self.assertAlmostEqual(ev("7/2"), 3.5)
def test_exact_division(self):
self.assertEqual(ev("4/2"), 2.0)
def test_div_by_zero_raises_eval_error(self):
with self.assertRaises(EvalError):
ev("1/0")
def test_div_by_zero_not_zero_division_error(self):
try:
ev("1/0")
except EvalError:
pass
except ZeroDivisionError:
self.fail("ZeroDivisionError escaped; expected EvalError")
def test_div_by_zero_expression(self):
with self.assertRaises(EvalError):
ev("5/(3-3)")
class D3ResultType(unittest.TestCase):
"""_format is tested indirectly through the CLI; here we check evaluate() types."""
def test_int_input_returns_int(self):
self.assertIsInstance(ev("3"), int)
def test_non_whole_div_returns_float(self):
result = ev("7/2")
self.assertIsInstance(result, float)
self.assertAlmostEqual(result, 3.5)
def test_whole_div_result_is_float_value_2(self):
result = ev("4/2")
self.assertAlmostEqual(result, 2.0)
class D4CLI(unittest.TestCase):
def _run(self, expr):
return subprocess.run(
[sys.executable, "calc.py", expr],
capture_output=True,
text=True,
)
def test_precedence_14(self):
r = self._run("2+3*4")
self.assertEqual(r.returncode, 0)
self.assertEqual(r.stdout.strip(), "14")
def test_paren_20(self):
r = self._run("(2+3)*4")
self.assertEqual(r.returncode, 0)
self.assertEqual(r.stdout.strip(), "20")
def test_true_division_3_5(self):
r = self._run("7/2")
self.assertEqual(r.returncode, 0)
self.assertEqual(r.stdout.strip(), "3.5")
def test_whole_division_no_trailing_dot(self):
r = self._run("4/2")
self.assertEqual(r.returncode, 0)
self.assertEqual(r.stdout.strip(), "2")
def test_div_by_zero_stderr_nonzero(self):
r = self._run("1/0")
self.assertNotEqual(r.returncode, 0)
self.assertGreater(len(r.stderr.strip()), 0)
self.assertEqual(r.stdout.strip(), "")
def test_invalid_expr_stderr_nonzero(self):
r = self._run("1 +")
self.assertNotEqual(r.returncode, 0)
self.assertGreater(len(r.stderr.strip()), 0)
self.assertEqual(r.stdout.strip(), "")
if __name__ == "__main__":
unittest.main()

View File

@ -0,0 +1,126 @@
"""Unit tests for calc.lexer — covers D1D3."""
import unittest
from calc.lexer import tokenize, Token, LexError
def kinds(src: str) -> list[str]:
return [t.kind for t in tokenize(src)]
def values(src: str) -> list:
return [t.value for t in tokenize(src)]
class TestNumbers(unittest.TestCase):
def test_integer(self):
toks = tokenize("42")
self.assertEqual(toks, [Token("NUMBER", 42), Token("EOF", None)])
self.assertIsInstance(toks[0].value, int)
def test_float_standard(self):
toks = tokenize("3.14")
self.assertEqual(len(toks), 2)
self.assertEqual(toks[0].kind, "NUMBER")
self.assertAlmostEqual(toks[0].value, 3.14)
self.assertIsInstance(toks[0].value, float)
def test_float_leading_dot(self):
toks = tokenize(".5")
self.assertEqual(toks[0].kind, "NUMBER")
self.assertAlmostEqual(toks[0].value, 0.5)
self.assertIsInstance(toks[0].value, float)
def test_float_trailing_dot(self):
toks = tokenize("10.")
self.assertEqual(toks[0].kind, "NUMBER")
self.assertAlmostEqual(toks[0].value, 10.0)
self.assertIsInstance(toks[0].value, float)
def test_zero(self):
toks = tokenize("0")
self.assertEqual(toks[0], Token("NUMBER", 0))
class TestOperatorsAndParens(unittest.TestCase):
def test_plus(self):
self.assertIn("PLUS", kinds("1+2"))
def test_minus(self):
self.assertIn("MINUS", kinds("1-2"))
def test_star(self):
self.assertIn("STAR", kinds("1*2"))
def test_slash(self):
self.assertIn("SLASH", kinds("1/2"))
def test_lparen(self):
self.assertIn("LPAREN", kinds("(1)"))
def test_rparen(self):
self.assertIn("RPAREN", kinds("(1)"))
def test_expr_kinds(self):
self.assertEqual(
kinds("1+2*3"),
["NUMBER", "PLUS", "NUMBER", "STAR", "NUMBER", "EOF"],
)
def test_eof_always_last(self):
for src in ["", "1", "1+2", "()"]:
self.assertEqual(tokenize(src)[-1].kind, "EOF")
class TestWhitespaceAndErrors(unittest.TestCase):
def test_spaces_between_tokens(self):
self.assertEqual(
kinds(" 12 + 3 "),
["NUMBER", "PLUS", "NUMBER", "EOF"],
)
toks = tokenize(" 12 + 3 ")
self.assertEqual(toks[0].value, 12)
self.assertEqual(toks[2].value, 3)
def test_tabs_skipped(self):
self.assertEqual(kinds("\t1\t+\t2\t"), ["NUMBER", "PLUS", "NUMBER", "EOF"])
def test_complex_expr(self):
self.assertEqual(
kinds("3.5*(1-2)"),
["NUMBER", "STAR", "LPAREN", "NUMBER", "MINUS", "NUMBER", "RPAREN", "EOF"],
)
toks = tokenize("3.5*(1-2)")
self.assertAlmostEqual(toks[0].value, 3.5)
self.assertEqual(toks[3].value, 1)
self.assertEqual(toks[5].value, 2)
def test_invalid_at_raises(self):
with self.assertRaises(LexError):
tokenize("1 @ 2")
def test_invalid_dollar_raises(self):
with self.assertRaises(LexError):
tokenize("$")
def test_invalid_letter_raises(self):
with self.assertRaises(LexError):
tokenize("a")
def test_lex_error_message_contains_char(self):
try:
tokenize("1 @ 2")
self.fail("LexError not raised")
except LexError as e:
self.assertIn("@", str(e))
def test_lex_error_message_contains_position(self):
try:
tokenize("1 @ 2")
self.fail("LexError not raised")
except LexError as e:
self.assertIn("2", str(e))
if __name__ == "__main__":
unittest.main()

View File

@ -0,0 +1,133 @@
"""Tests for calc.parser — asserts on AST structure, not evaluation."""
import unittest
from .lexer import tokenize
from .parser import parse, ParseError, Num, BinOp, Unary
def p(src: str):
return parse(tokenize(src))
class TestPrecedence(unittest.TestCase):
"""D1 — * and / bind tighter than + and -."""
def test_add_mul(self):
# 1+2*3 => BinOp('+', Num(1), BinOp('*', Num(2), Num(3)))
self.assertEqual(p("1+2*3"), BinOp("+", Num(1), BinOp("*", Num(2), Num(3))))
def test_mul_add(self):
# 2*3+1 => BinOp('+', BinOp('*', Num(2), Num(3)), Num(1))
self.assertEqual(p("2*3+1"), BinOp("+", BinOp("*", Num(2), Num(3)), Num(1)))
def test_sub_div(self):
# 10-4/2 => BinOp('-', Num(10), BinOp('/', Num(4), Num(2)))
self.assertEqual(p("10-4/2"), BinOp("-", Num(10), BinOp("/", Num(4), Num(2))))
def test_mixed_four_ops(self):
# 1+2*3-4/2 => BinOp('-', BinOp('+', Num(1), BinOp('*', Num(2), Num(3))),
# BinOp('/', Num(4), Num(2)))
self.assertEqual(
p("1+2*3-4/2"),
BinOp(
"-",
BinOp("+", Num(1), BinOp("*", Num(2), Num(3))),
BinOp("/", Num(4), Num(2)),
),
)
class TestLeftAssociativity(unittest.TestCase):
"""D2 — same-precedence operators associate left."""
def test_subtraction_left(self):
# 8-3-2 => BinOp('-', BinOp('-', Num(8), Num(3)), Num(2))
self.assertEqual(p("8-3-2"), BinOp("-", BinOp("-", Num(8), Num(3)), Num(2)))
def test_division_left(self):
# 8/4/2 => BinOp('/', BinOp('/', Num(8), Num(4)), Num(2))
self.assertEqual(p("8/4/2"), BinOp("/", BinOp("/", Num(8), Num(4)), Num(2)))
def test_addition_left(self):
# 1+2+3 => BinOp('+', BinOp('+', Num(1), Num(2)), Num(3))
self.assertEqual(p("1+2+3"), BinOp("+", BinOp("+", Num(1), Num(2)), Num(3)))
def test_multiplication_left(self):
# 2*3*4 => BinOp('*', BinOp('*', Num(2), Num(3)), Num(4))
self.assertEqual(p("2*3*4"), BinOp("*", BinOp("*", Num(2), Num(3)), Num(4)))
class TestParentheses(unittest.TestCase):
"""D3 — parentheses override precedence."""
def test_paren_add_then_mul(self):
# (1+2)*3 => BinOp('*', BinOp('+', Num(1), Num(2)), Num(3))
self.assertEqual(p("(1+2)*3"), BinOp("*", BinOp("+", Num(1), Num(2)), Num(3)))
def test_paren_nested(self):
# (1+(2*3)) => BinOp('+', Num(1), BinOp('*', Num(2), Num(3)))
self.assertEqual(
p("(1+(2*3))"), BinOp("+", Num(1), BinOp("*", Num(2), Num(3)))
)
def test_paren_changes_assoc(self):
# 8-(3-2) => BinOp('-', Num(8), BinOp('-', Num(3), Num(2)))
self.assertEqual(p("8-(3-2)"), BinOp("-", Num(8), BinOp("-", Num(3), Num(2))))
def test_paren_single_number(self):
self.assertEqual(p("(42)"), Num(42))
class TestUnaryMinus(unittest.TestCase):
"""D4 — leading and nested unary minus."""
def test_simple_unary(self):
self.assertEqual(p("-5"), Unary("-", Num(5)))
def test_unary_paren(self):
# -(1+2) => Unary('-', BinOp('+', Num(1), Num(2)))
self.assertEqual(p("-(1+2)"), Unary("-", BinOp("+", Num(1), Num(2))))
def test_mul_unary(self):
# 3 * -2 => BinOp('*', Num(3), Unary('-', Num(2)))
self.assertEqual(p("3 * -2"), BinOp("*", Num(3), Unary("-", Num(2))))
def test_double_unary(self):
# --5 => Unary('-', Unary('-', Num(5)))
self.assertEqual(p("--5"), Unary("-", Unary("-", Num(5))))
def test_unary_in_expr(self):
# 1 + -2 => BinOp('+', Num(1), Unary('-', Num(2)))
self.assertEqual(p("1 + -2"), BinOp("+", Num(1), Unary("-", Num(2))))
class TestErrors(unittest.TestCase):
"""D5 — malformed input raises ParseError."""
def test_trailing_operator(self):
with self.assertRaises(ParseError):
p("1 +")
def test_unclosed_paren(self):
with self.assertRaises(ParseError):
p("(1")
def test_two_numbers(self):
with self.assertRaises(ParseError):
p("1 2")
def test_close_open_paren(self):
with self.assertRaises(ParseError):
p(")(")
def test_empty_string(self):
with self.assertRaises(ParseError):
p("")
def test_only_operator(self):
with self.assertRaises(ParseError):
p("*")
if __name__ == "__main__":
unittest.main()