artifacts: add calculators/ — the 30 built calculators (5/variant) + machine-docs + git logs
This commit is contained in:
@@ -0,0 +1,36 @@
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from calc.parser import Num, BinOp, Unary
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class EvalError(Exception):
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pass
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def evaluate(node) -> "int | float":
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if isinstance(node, Num):
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return node.value
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if isinstance(node, Unary):
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if node.op == '-':
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return -evaluate(node.operand)
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raise EvalError(f"unknown unary op: {node.op!r}")
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if isinstance(node, BinOp):
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left = evaluate(node.left)
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right = evaluate(node.right)
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if node.op == '+':
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return left + right
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if node.op == '-':
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return left - right
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if node.op == '*':
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return left * right
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if node.op == '/':
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if right == 0:
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raise EvalError("division by zero")
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return left / right
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raise EvalError(f"unknown binary op: {node.op!r}")
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raise EvalError(f"unknown node type: {type(node).__name__}")
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def format_result(value) -> str:
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"""Whole-valued results print without .0; non-whole as float."""
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if isinstance(value, float) and value == int(value):
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return str(int(value))
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return str(value)
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@@ -0,0 +1,53 @@
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class LexError(Exception):
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pass
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class Token:
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def __init__(self, kind: str, value):
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self.kind = kind
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self.value = value
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def __repr__(self):
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return f"{self.kind}({self.value!r})"
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def __eq__(self, other):
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return isinstance(other, Token) and self.kind == other.kind and self.value == other.value
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_SINGLE = {'+': 'PLUS', '-': 'MINUS', '*': 'STAR', '/': 'SLASH', '(': 'LPAREN', ')': 'RPAREN'}
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def tokenize(src: str) -> list:
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tokens = []
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i = 0
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while i < len(src):
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ch = src[i]
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if ch in ' \t':
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i += 1
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continue
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if ch.isdigit() or ch == '.':
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j = i
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has_dot = False
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while j < len(src) and (src[j].isdigit() or (src[j] == '.' and not has_dot)):
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if src[j] == '.':
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has_dot = True
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j += 1
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num_str = src[i:j]
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if num_str == '.':
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raise LexError(f"Invalid character '.' at position {i}")
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value = float(num_str) if has_dot else int(num_str)
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tokens.append(Token('NUMBER', value))
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i = j
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continue
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if ch in _SINGLE:
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tokens.append(Token(_SINGLE[ch], ch))
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i += 1
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continue
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raise LexError(f"Invalid character {ch!r} at position {i}")
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tokens.append(Token('EOF', None))
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return tokens
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@@ -0,0 +1,115 @@
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class ParseError(Exception):
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pass
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class Num:
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def __init__(self, value):
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self.value = value
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def __repr__(self):
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return f"Num({self.value!r})"
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def __eq__(self, other):
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return isinstance(other, Num) and self.value == other.value
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class BinOp:
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def __init__(self, op: str, left, right):
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self.op = op
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self.left = left
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self.right = right
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def __repr__(self):
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return f"BinOp({self.op!r}, {self.left!r}, {self.right!r})"
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def __eq__(self, other):
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return (isinstance(other, BinOp) and self.op == other.op
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and self.left == other.left and self.right == other.right)
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class Unary:
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def __init__(self, op: str, operand):
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self.op = op
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self.operand = operand
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def __repr__(self):
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return f"Unary({self.op!r}, {self.operand!r})"
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def __eq__(self, other):
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return (isinstance(other, Unary) and self.op == other.op
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and self.operand == other.operand)
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class _Parser:
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def __init__(self, tokens):
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self._tokens = tokens
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self._pos = 0
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def _current(self):
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return self._tokens[self._pos]
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def _advance(self):
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tok = self._tokens[self._pos]
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if tok.kind != 'EOF':
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self._pos += 1
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return tok
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def _expect(self, kind):
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tok = self._current()
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if tok.kind != kind:
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raise ParseError(f"expected {kind}, got {tok!r}")
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return self._advance()
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def expr(self):
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left = self._term()
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while self._current().kind in ('PLUS', 'MINUS'):
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op = self._advance().value
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right = self._term()
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left = BinOp(op, left, right)
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return left
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def _term(self):
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left = self._unary()
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while self._current().kind in ('STAR', 'SLASH'):
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op = self._advance().value
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right = self._unary()
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left = BinOp(op, left, right)
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return left
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def _unary(self):
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if self._current().kind == 'MINUS':
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self._advance()
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operand = self._unary()
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return Unary('-', operand)
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return self._primary()
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def _primary(self):
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tok = self._current()
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if tok.kind == 'NUMBER':
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self._advance()
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return Num(tok.value)
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if tok.kind == 'LPAREN':
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self._advance()
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node = self.expr()
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self._expect('RPAREN')
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return node
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raise ParseError(f"unexpected token {tok!r}")
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def parse(tokens) -> object:
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"""Parse a token list (from lexer.tokenize) into an AST.
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Returns the root Node, one of:
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Num(value) — numeric literal
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BinOp(op, left, right) — binary + - * /
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Unary(op, operand) — unary -
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Raises ParseError on malformed input.
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"""
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if not tokens or (len(tokens) == 1 and tokens[0].kind == 'EOF'):
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raise ParseError("empty input")
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p = _Parser(tokens)
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node = p.expr()
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if p._current().kind != 'EOF':
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raise ParseError(f"unexpected token after expression: {p._current()!r}")
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return node
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@@ -0,0 +1,83 @@
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import subprocess
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import sys
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import unittest
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from calc.lexer import tokenize
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from calc.parser import parse
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from calc.evaluator import EvalError, evaluate, format_result
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def calc(expr):
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return evaluate(parse(tokenize(expr)))
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class TestArithmetic(unittest.TestCase):
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def test_add_mul_precedence(self):
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self.assertEqual(calc("2+3*4"), 14)
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def test_parens(self):
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self.assertEqual(calc("(2+3)*4"), 20)
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def test_left_assoc_subtract(self):
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self.assertEqual(calc("8-3-2"), 3)
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def test_unary_minus(self):
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self.assertEqual(calc("-2+5"), 3)
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def test_unary_minus_rhs(self):
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self.assertEqual(calc("2*-3"), -6)
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class TestDivision(unittest.TestCase):
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def test_true_division(self):
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self.assertAlmostEqual(calc("7/2"), 3.5)
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def test_division_by_zero(self):
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with self.assertRaises(EvalError):
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calc("1/0")
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def test_division_by_zero_not_bare(self):
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try:
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calc("1/0")
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except EvalError:
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pass
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except ZeroDivisionError:
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self.fail("ZeroDivisionError escaped the API; should be EvalError")
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class TestResultType(unittest.TestCase):
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def test_whole_float_prints_as_int(self):
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self.assertEqual(format_result(calc("4/2")), "2")
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def test_non_whole_prints_as_float(self):
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self.assertEqual(format_result(calc("7/2")), "3.5")
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def test_integer_result(self):
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self.assertEqual(format_result(calc("2+3*4")), "14")
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class TestCLI(unittest.TestCase):
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def _run(self, expr):
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return subprocess.run(
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[sys.executable, "calc.py", expr],
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capture_output=True, text=True
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)
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def test_valid_expression(self):
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r = self._run("2+3*4")
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self.assertEqual(r.returncode, 0)
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self.assertEqual(r.stdout.strip(), "14")
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def test_invalid_expression_stderr_nonzero(self):
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r = self._run("1 +")
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self.assertNotEqual(r.returncode, 0)
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self.assertTrue(r.stderr.strip(), "expected error message on stderr")
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def test_division_by_zero_cli(self):
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r = self._run("1/0")
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self.assertNotEqual(r.returncode, 0)
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self.assertTrue(r.stderr.strip())
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if __name__ == "__main__":
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unittest.main()
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@@ -0,0 +1,86 @@
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import unittest
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from calc.lexer import tokenize, Token, LexError
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def kinds(src):
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return [t.kind for t in tokenize(src)]
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class TestNumbers(unittest.TestCase):
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def test_integer(self):
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tokens = tokenize("42")
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self.assertEqual(tokens, [Token('NUMBER', 42), Token('EOF', None)])
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def test_float(self):
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tokens = tokenize("3.14")
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self.assertEqual(tokens[0].kind, 'NUMBER')
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self.assertAlmostEqual(tokens[0].value, 3.14)
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self.assertEqual(tokens[1].kind, 'EOF')
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def test_leading_dot(self):
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tokens = tokenize(".5")
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self.assertEqual(tokens[0].kind, 'NUMBER')
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self.assertAlmostEqual(tokens[0].value, 0.5)
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def test_trailing_dot(self):
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tokens = tokenize("10.")
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self.assertEqual(tokens[0].kind, 'NUMBER')
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self.assertAlmostEqual(tokens[0].value, 10.0)
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class TestOperatorsAndParens(unittest.TestCase):
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def test_each_operator(self):
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self.assertEqual(kinds("+"), ['PLUS', 'EOF'])
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self.assertEqual(kinds("-"), ['MINUS', 'EOF'])
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self.assertEqual(kinds("*"), ['STAR', 'EOF'])
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self.assertEqual(kinds("/"), ['SLASH', 'EOF'])
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self.assertEqual(kinds("("), ['LPAREN', 'EOF'])
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self.assertEqual(kinds(")"), ['RPAREN', 'EOF'])
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def test_expression_kinds(self):
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self.assertEqual(kinds("1+2*3"), ['NUMBER', 'PLUS', 'NUMBER', 'STAR', 'NUMBER', 'EOF'])
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class TestWhitespace(unittest.TestCase):
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def test_spaces(self):
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tokens = tokenize(" 12 + 3 ")
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self.assertEqual([t.kind for t in tokens], ['NUMBER', 'PLUS', 'NUMBER', 'EOF'])
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self.assertEqual(tokens[0].value, 12)
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self.assertEqual(tokens[2].value, 3)
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def test_tabs(self):
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tokens = tokenize("1\t+\t2")
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self.assertEqual([t.kind for t in tokens], ['NUMBER', 'PLUS', 'NUMBER', 'EOF'])
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class TestErrors(unittest.TestCase):
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def test_at_sign_raises_lex_error(self):
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with self.assertRaises(LexError) as ctx:
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tokenize("1 @ 2")
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msg = str(ctx.exception)
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self.assertIn('@', msg)
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self.assertIn('2', msg) # position 2
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def test_dollar_raises_lex_error(self):
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with self.assertRaises(LexError):
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tokenize("$")
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def test_letter_raises_lex_error(self):
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with self.assertRaises(LexError):
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tokenize("abc")
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class TestComplex(unittest.TestCase):
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def test_float_expr_with_parens(self):
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tokens = tokenize("3.5*(1-2)")
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self.assertEqual(
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[t.kind for t in tokens],
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['NUMBER', 'STAR', 'LPAREN', 'NUMBER', 'MINUS', 'NUMBER', 'RPAREN', 'EOF']
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)
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self.assertAlmostEqual(tokens[0].value, 3.5)
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self.assertEqual(tokens[3].value, 1)
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self.assertEqual(tokens[5].value, 2)
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if __name__ == '__main__':
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unittest.main()
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@@ -0,0 +1,91 @@
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import unittest
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from calc.lexer import tokenize
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from calc.parser import parse, ParseError, Num, BinOp, Unary
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def p(src):
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return parse(tokenize(src))
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class TestD1Precedence(unittest.TestCase):
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def test_add_then_mul(self):
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# 1+2*3 must be 1+(2*3), not (1+2)*3
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self.assertEqual(p('1+2*3'), BinOp('+', Num(1), BinOp('*', Num(2), Num(3))))
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def test_mul_then_add(self):
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# 2*3+1 must be (2*3)+1
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self.assertEqual(p('2*3+1'), BinOp('+', BinOp('*', Num(2), Num(3)), Num(1)))
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def test_sub_then_div(self):
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# 9-4/2 must be 9-(4/2)
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self.assertEqual(p('9-4/2'), BinOp('-', Num(9), BinOp('/', Num(4), Num(2))))
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class TestD2LeftAssociativity(unittest.TestCase):
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def test_subtraction(self):
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# 8-3-2 must be (8-3)-2
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self.assertEqual(p('8-3-2'), BinOp('-', BinOp('-', Num(8), Num(3)), Num(2)))
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def test_division(self):
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# 8/4/2 must be (8/4)/2
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self.assertEqual(p('8/4/2'), BinOp('/', BinOp('/', Num(8), Num(4)), Num(2)))
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def test_addition(self):
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# 1+2+3 must be (1+2)+3
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self.assertEqual(p('1+2+3'), BinOp('+', BinOp('+', Num(1), Num(2)), Num(3)))
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class TestD3Parentheses(unittest.TestCase):
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def test_override_precedence(self):
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# (1+2)*3: + is under *
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self.assertEqual(p('(1+2)*3'), BinOp('*', BinOp('+', Num(1), Num(2)), Num(3)))
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def test_nested_parens(self):
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# ((2+3)) same as 2+3
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self.assertEqual(p('((2+3))'), BinOp('+', Num(2), Num(3)))
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def test_parens_right(self):
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# 3*(1+2): + is under *, on the right
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self.assertEqual(p('3*(1+2)'), BinOp('*', Num(3), BinOp('+', Num(1), Num(2))))
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class TestD4UnaryMinus(unittest.TestCase):
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def test_simple(self):
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self.assertEqual(p('-5'), Unary('-', Num(5)))
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def test_paren(self):
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# -(1+2)
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self.assertEqual(p('-(1+2)'), Unary('-', BinOp('+', Num(1), Num(2))))
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def test_after_mul(self):
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# 3 * -2
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self.assertEqual(p('3 * -2'), BinOp('*', Num(3), Unary('-', Num(2))))
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def test_double_unary(self):
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# --5 = Unary('-', Unary('-', Num(5)))
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self.assertEqual(p('--5'), Unary('-', Unary('-', Num(5))))
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class TestD5Errors(unittest.TestCase):
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def _raises(self, src):
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with self.assertRaises(ParseError, msg=f"expected ParseError for {src!r}"):
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p(src)
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def test_trailing_op(self):
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self._raises('1 +')
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def test_unclosed_paren(self):
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self._raises('(1')
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def test_two_numbers(self):
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self._raises('1 2')
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def test_close_open_paren(self):
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self._raises(')(')
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def test_empty(self):
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self._raises('')
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if __name__ == '__main__':
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unittest.main()
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