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

calculators/builder-solo/run-03/calc/evaluator.py

@@ -0,0 +1,39 @@
+from calc.parser import Num, Unary, BinOp, Node
+
+
+class EvalError(Exception):
+    pass
+
+
+def evaluate(node: Node):
+    """Walk the AST and return an int or float.
+
+    Result-type rule: if the result is mathematically whole-valued it is
+    returned as int; non-whole results are returned as float.  This rule is
+    applied after every operation so intermediate values are also normalised.
+    """
+    if isinstance(node, Num):
+        return _normalise(node.value)
+    if isinstance(node, Unary):
+        return _normalise(-evaluate(node.operand))
+    if isinstance(node, BinOp):
+        left = evaluate(node.left)
+        right = evaluate(node.right)
+        if node.op == '+':
+            return _normalise(left + right)
+        if node.op == '-':
+            return _normalise(left - right)
+        if node.op == '*':
+            return _normalise(left * right)
+        if node.op == '/':
+            if right == 0:
+                raise EvalError("division by zero")
+            return _normalise(left / right)
+    raise EvalError(f"unknown node type: {type(node).__name__}")
+
+
+def _normalise(value):
+    """Return int when value is whole-valued, float otherwise."""
+    if isinstance(value, float) and value == int(value):
+        return int(value)
+    return value

calculators/builder-solo/run-03/calc/lexer.py

@@ -0,0 +1,56 @@
+from dataclasses import dataclass
+from typing import Union
+
+
+class LexError(Exception):
+    pass
+
+
+@dataclass
+class Token:
+    kind: str
+    value: Union[int, float, str, None]
+
+
+def tokenize(src: str) -> list:
+    tokens = []
+    i = 0
+    while i < len(src):
+        ch = src[i]
+
+        if ch in ' \t':
+            i += 1
+            continue
+
+        if ch.isdigit() or ch == '.':
+            j = i
+            has_dot = False
+            while j < len(src) and (src[j].isdigit() or (src[j] == '.' and not has_dot)):
+                if src[j] == '.':
+                    has_dot = True
+                j += 1
+            raw = src[i:j]
+            value = float(raw) if has_dot else int(raw)
+            tokens.append(Token('NUMBER', value))
+            i = j
+            continue
+
+        if ch == '+':
+            tokens.append(Token('PLUS', '+'))
+        elif ch == '-':
+            tokens.append(Token('MINUS', '-'))
+        elif ch == '*':
+            tokens.append(Token('STAR', '*'))
+        elif ch == '/':
+            tokens.append(Token('SLASH', '/'))
+        elif ch == '(':
+            tokens.append(Token('LPAREN', '('))
+        elif ch == ')':
+            tokens.append(Token('RPAREN', ')'))
+        else:
+            raise LexError(f"unexpected character {ch!r} at position {i}")
+
+        i += 1
+
+    tokens.append(Token('EOF', None))
+    return tokens

calculators/builder-solo/run-03/calc/parser.py

@@ -0,0 +1,140 @@
+from dataclasses import dataclass
+from typing import Union
+from calc.lexer import Token
+
+
+class ParseError(Exception):
+    pass
+
+
+@dataclass
+class Num:
+    """Leaf node: a numeric literal."""
+    value: Union[int, float]
+
+    def __repr__(self):
+        return f"Num({self.value!r})"
+
+
+@dataclass
+class Unary:
+    """Unary operator node: op is '-', operand is the inner Node."""
+    op: str
+    operand: object
+
+    def __repr__(self):
+        return f"Unary({self.op!r}, {self.operand!r})"
+
+
+@dataclass
+class BinOp:
+    """Binary operator node. op is one of '+', '-', '*', '/'.
+    Precedence and associativity are encoded in the tree structure, not here.
+    """
+    op: str
+    left: object
+    right: object
+
+    def __repr__(self):
+        return f"BinOp({self.op!r}, {self.left!r}, {self.right!r})"
+
+
+Node = Union[Num, Unary, BinOp]
+
+
+class _Parser:
+    def __init__(self, tokens: list):
+        self._tokens = tokens
+        self._pos = 0
+
+    def _peek(self) -> Token:
+        return self._tokens[self._pos]
+
+    def _consume(self, kind: str) -> Token:
+        tok = self._peek()
+        if tok.kind != kind:
+            raise ParseError(
+                f"expected {kind}, got {tok.kind!r} ({tok.value!r})"
+            )
+        self._pos += 1
+        return tok
+
+    def _advance(self) -> Token:
+        tok = self._tokens[self._pos]
+        self._pos += 1
+        return tok
+
+    def parse(self) -> Node:
+        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}) after expression"
+            )
+        return node
+
+    # Grammar (lowest to highest precedence):
+    #   expr   -> term  (('+' | '-') term)*
+    #   term   -> unary (('*' | '/') unary)*
+    #   unary  -> '-' unary | primary
+    #   primary-> NUMBER | '(' expr ')'
+
+    def _expr(self) -> Node:
+        node = self._term()
+        while self._peek().kind in ('PLUS', 'MINUS'):
+            op_tok = self._advance()
+            op = op_tok.value
+            right = self._term()
+            node = BinOp(op, node, right)
+        return node
+
+    def _term(self) -> Node:
+        node = self._unary()
+        while self._peek().kind in ('STAR', 'SLASH'):
+            op_tok = self._advance()
+            op = op_tok.value
+            right = self._unary()
+            node = BinOp(op, node, right)
+        return node
+
+    def _unary(self) -> Node:
+        if self._peek().kind == 'MINUS':
+            self._advance()
+            operand = self._unary()
+            return Unary('-', operand)
+        return self._primary()
+
+    def _primary(self) -> Node:
+        tok = self._peek()
+        if tok.kind == 'NUMBER':
+            self._advance()
+            return Num(tok.value)
+        if tok.kind == 'LPAREN':
+            self._advance()
+            node = self._expr()
+            if self._peek().kind != 'RPAREN':
+                raise ParseError(
+                    f"expected ')' but got {self._peek().kind!r}"
+                )
+            self._advance()
+            return node
+        if tok.kind == 'EOF':
+            raise ParseError("unexpected end of input")
+        raise ParseError(
+            f"unexpected token {tok.kind!r} ({tok.value!r})"
+        )
+
+
+def parse(tokens: list) -> Node:
+    """Parse a token list (from lexer.tokenize) into an AST Node.
+
+    AST node shapes:
+      Num(value)              — numeric literal
+      Unary('-', operand)     — unary negation
+      BinOp(op, left, right)  — binary operation; op in {'+','-','*','/'}
+
+    Raises ParseError on malformed input.
+    """
+    return _Parser(tokens).parse()

calculators/builder-solo/run-03/calc/test_evaluator.py

@@ -0,0 +1,87 @@
+import unittest
+from calc.lexer import tokenize
+from calc.parser import parse
+from calc.evaluator import evaluate, EvalError
+
+
+def calc(expr):
+    return evaluate(parse(tokenize(expr)))
+
+
+class TestD1Arithmetic(unittest.TestCase):
+    def test_addition(self):
+        self.assertEqual(calc("1+2"), 3)
+
+    def test_precedence_mul_over_add(self):
+        self.assertEqual(calc("2+3*4"), 14)
+
+    def test_parens_override_precedence(self):
+        self.assertEqual(calc("(2+3)*4"), 20)
+
+    def test_left_assoc_subtraction(self):
+        self.assertEqual(calc("8-3-2"), 3)
+
+    def test_unary_minus_at_start(self):
+        self.assertEqual(calc("-2+5"), 3)
+
+    def test_unary_minus_after_operator(self):
+        self.assertEqual(calc("2*-3"), -6)
+
+    def test_double_unary_minus(self):
+        self.assertEqual(calc("--5"), 5)
+
+    def test_multiply(self):
+        self.assertEqual(calc("3*4"), 12)
+
+
+class TestD2Division(unittest.TestCase):
+    def test_true_division(self):
+        self.assertEqual(calc("7/2"), 3.5)
+
+    def test_division_by_zero_raises_eval_error(self):
+        with self.assertRaises(EvalError):
+            calc("1/0")
+
+    def test_division_by_zero_not_bare_exception(self):
+        """EvalError (not ZeroDivisionError) must escape the API."""
+        try:
+            calc("1/0")
+        except EvalError:
+            pass
+        except ZeroDivisionError:
+            self.fail("ZeroDivisionError must not escape evaluate()")
+
+    def test_expression_division_by_zero(self):
+        with self.assertRaises(EvalError):
+            calc("5/(3-3)")
+
+
+class TestD3ResultType(unittest.TestCase):
+    def test_whole_division_returns_int(self):
+        result = calc("4/2")
+        self.assertEqual(result, 2)
+        self.assertIsInstance(result, int)
+
+    def test_non_whole_division_returns_float(self):
+        result = calc("7/2")
+        self.assertEqual(result, 3.5)
+        self.assertIsInstance(result, float)
+
+    def test_int_arithmetic_stays_int(self):
+        result = calc("3+4")
+        self.assertIsInstance(result, int)
+
+    def test_float_literal_whole_normalised(self):
+        result = calc("2.0+1")
+        self.assertIsInstance(result, int)
+        self.assertEqual(result, 3)
+
+    def test_result_type_str_no_dot(self):
+        self.assertEqual(str(calc("4/2")), "2")
+
+    def test_result_type_str_with_decimal(self):
+        self.assertEqual(str(calc("7/2")), "3.5")
+
+
+if __name__ == "__main__":
+    unittest.main()

calculators/builder-solo/run-03/calc/test_lexer.py

@@ -0,0 +1,95 @@
+import unittest
+from calc.lexer import tokenize, Token, LexError
+
+
+def kinds(src):
+    return [t.kind for t in tokenize(src)]
+
+
+def kv(src):
+    return [(t.kind, t.value) for t in tokenize(src)]
+
+
+class TestNumbers(unittest.TestCase):
+    def test_integer(self):
+        toks = tokenize("42")
+        self.assertEqual(toks[0].kind, 'NUMBER')
+        self.assertEqual(toks[0].value, 42)
+        self.assertIsInstance(toks[0].value, int)
+        self.assertEqual(toks[1].kind, 'EOF')
+
+    def test_float(self):
+        toks = tokenize("3.14")
+        self.assertEqual(toks[0].kind, 'NUMBER')
+        self.assertAlmostEqual(toks[0].value, 3.14)
+        self.assertIsInstance(toks[0].value, float)
+
+    def test_leading_dot(self):
+        toks = tokenize(".5")
+        self.assertEqual(toks[0].kind, 'NUMBER')
+        self.assertAlmostEqual(toks[0].value, 0.5)
+
+    def test_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].value, 0)
+
+
+class TestOperatorsAndParens(unittest.TestCase):
+    def test_plus(self):
+        self.assertIn('PLUS', kinds("+"))
+
+    def test_minus(self):
+        self.assertIn('MINUS', kinds("-"))
+
+    def test_star(self):
+        self.assertIn('STAR', kinds("*"))
+
+    def test_slash(self):
+        self.assertIn('SLASH', kinds("/"))
+
+    def test_lparen(self):
+        self.assertIn('LPAREN', kinds("("))
+
+    def test_rparen(self):
+        self.assertIn('RPAREN', kinds(")"))
+
+    def test_expr(self):
+        self.assertEqual(kinds("1+2*3"), ['NUMBER', 'PLUS', 'NUMBER', 'STAR', 'NUMBER', 'EOF'])
+
+
+class TestWhitespaceAndErrors(unittest.TestCase):
+    def test_whitespace_skipped(self):
+        self.assertEqual(kinds("  12  +  3 "), ['NUMBER', 'PLUS', 'NUMBER', 'EOF'])
+
+    def test_complex_expr(self):
+        self.assertEqual(kinds("3.5*(1-2)"),
+                         ['NUMBER', 'STAR', 'LPAREN', 'NUMBER', 'MINUS', 'NUMBER', 'RPAREN', 'EOF'])
+
+    def test_lex_error_at(self):
+        with self.assertRaises(LexError) as ctx:
+            tokenize("1 @ 2")
+        self.assertIn('@', str(ctx.exception))
+
+    def test_lex_error_dollar(self):
+        with self.assertRaises(LexError):
+            tokenize("$5")
+
+    def test_lex_error_letter(self):
+        with self.assertRaises(LexError):
+            tokenize("abc")
+
+    def test_lex_error_position_in_message(self):
+        with self.assertRaises(LexError) as ctx:
+            tokenize("1 @ 2")
+        msg = str(ctx.exception)
+        self.assertIn('2', msg)  # position 2
+
+
+if __name__ == '__main__':
+    unittest.main()

calculators/builder-solo/run-03/calc/test_parser.py

@@ -0,0 +1,151 @@
+import unittest
+from calc.lexer import tokenize
+from calc.parser import parse, ParseError, Num, BinOp, Unary
+
+
+def p(src):
+    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)))
+        tree = p("1+2*3")
+        self.assertEqual(tree, BinOp('+', Num(1), BinOp('*', Num(2), Num(3))))
+
+    def test_mul_add(self):
+        # 2*3+1 -> BinOp('+', BinOp('*', Num(2), Num(3)), Num(1))
+        tree = p("2*3+1")
+        self.assertEqual(tree, BinOp('+', BinOp('*', Num(2), Num(3)), Num(1)))
+
+    def test_sub_div(self):
+        # 10-6/2 -> BinOp('-', Num(10), BinOp('/', Num(6), Num(2)))
+        tree = p("10-6/2")
+        self.assertEqual(tree, BinOp('-', Num(10), BinOp('/', Num(6), Num(2))))
+
+
+class TestLeftAssociativity(unittest.TestCase):
+    """D2 — same-precedence operators associate left."""
+
+    def test_sub_sub(self):
+        # 8-3-2 -> BinOp('-', BinOp('-', Num(8), Num(3)), Num(2))
+        tree = p("8-3-2")
+        self.assertEqual(tree, BinOp('-', BinOp('-', Num(8), Num(3)), Num(2)))
+
+    def test_div_div(self):
+        # 8/4/2 -> BinOp('/', BinOp('/', Num(8), Num(4)), Num(2))
+        tree = p("8/4/2")
+        self.assertEqual(tree, BinOp('/', BinOp('/', Num(8), Num(4)), Num(2)))
+
+    def test_add_add(self):
+        tree = p("1+2+3")
+        self.assertEqual(tree, BinOp('+', BinOp('+', Num(1), Num(2)), Num(3)))
+
+    def test_mul_mul(self):
+        tree = p("2*3*4")
+        self.assertEqual(tree, BinOp('*', BinOp('*', Num(2), Num(3)), Num(4)))
+
+
+class TestParentheses(unittest.TestCase):
+    """D3 — parens override precedence."""
+
+    def test_paren_overrides(self):
+        # (1+2)*3 -> BinOp('*', BinOp('+', Num(1), Num(2)), Num(3))
+        tree = p("(1+2)*3")
+        self.assertEqual(tree, BinOp('*', BinOp('+', Num(1), Num(2)), Num(3)))
+
+    def test_nested_parens(self):
+        tree = p("((2+3))")
+        self.assertEqual(tree, BinOp('+', Num(2), Num(3)))
+
+    def test_paren_in_sum(self):
+        # 1+(2+3) -> BinOp('+', Num(1), BinOp('+', Num(2), Num(3)))
+        tree = p("1+(2+3)")
+        self.assertEqual(tree, BinOp('+', Num(1), BinOp('+', Num(2), Num(3))))
+
+
+class TestUnaryMinus(unittest.TestCase):
+    """D4 — leading and nested unary minus."""
+
+    def test_simple_unary(self):
+        tree = p("-5")
+        self.assertEqual(tree, Unary('-', Num(5)))
+
+    def test_unary_paren(self):
+        # -(1+2) -> Unary('-', BinOp('+', Num(1), Num(2)))
+        tree = p("-(1+2)")
+        self.assertEqual(tree, Unary('-', BinOp('+', Num(1), Num(2))))
+
+    def test_mul_unary(self):
+        # 3 * -2 -> BinOp('*', Num(3), Unary('-', Num(2)))
+        tree = p("3 * -2")
+        self.assertEqual(tree, BinOp('*', Num(3), Unary('-', Num(2))))
+
+    def test_double_unary(self):
+        # --5 -> Unary('-', Unary('-', Num(5)))
+        tree = p("--5")
+        self.assertEqual(tree, Unary('-', Unary('-', Num(5))))
+
+    def test_unary_in_expr(self):
+        tree = p("-1+2")
+        self.assertEqual(tree, BinOp('+', Unary('-', Num(1)), 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("*")
+
+    def test_unclosed_paren_complex(self):
+        with self.assertRaises(ParseError):
+            p("(1+2")
+
+
+class TestSimpleCases(unittest.TestCase):
+    """Basic sanity checks."""
+
+    def test_single_number(self):
+        self.assertEqual(p("42"), Num(42))
+
+    def test_float(self):
+        self.assertEqual(p("3.14"), Num(3.14))
+
+    def test_simple_add(self):
+        self.assertEqual(p("1+2"), BinOp('+', Num(1), Num(2)))
+
+    def test_simple_sub(self):
+        self.assertEqual(p("5-3"), BinOp('-', Num(5), Num(3)))
+
+    def test_simple_mul(self):
+        self.assertEqual(p("4*2"), BinOp('*', Num(4), Num(2)))
+
+    def test_simple_div(self):
+        self.assertEqual(p("8/2"), BinOp('/', Num(8), Num(2)))
+
+
+if __name__ == '__main__':
+    unittest.main()