From 753ced86da87024dbe6df02febc85f356cca7256 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 20:54:33 +0000
Subject: [PATCH 01/12] Initial plan
From 410a22fbc99aa5ada0538edc9dbae54eb829687e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 20:59:24 +0000
Subject: [PATCH 02/12] Implement #if and #elif support with expression parser
- Added expression.py module with Pratt parser for C preprocessor expressions
- Supports arithmetic, logical, comparison, and bitwise operators
- Supports defined() operator for checking macro definitions
- Added process_if() and process_elif() methods to Preprocessor class
- Added comprehensive unit tests for expression parsing
- Added comprehensive unit tests for #if and #elif directives
- All existing tests pass, 139 total tests with 96% coverage
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
simplecpreprocessor/core.py | 51 ++-
simplecpreprocessor/expression.py | 260 ++++++++++++++
simplecpreprocessor/tests/test_expression.py | 268 ++++++++++++++
simplecpreprocessor/tests/test_if_elif.py | 356 +++++++++++++++++++
4 files changed, 934 insertions(+), 1 deletion(-)
create mode 100644 simplecpreprocessor/expression.py
create mode 100644 simplecpreprocessor/tests/test_expression.py
create mode 100644 simplecpreprocessor/tests/test_if_elif.py
diff --git a/simplecpreprocessor/core.py b/simplecpreprocessor/core.py
index 7e0d763..a4454a3 100644
--- a/simplecpreprocessor/core.py
+++ b/simplecpreprocessor/core.py
@@ -1,6 +1,6 @@
import enum
-from . import filesystem, tokens, platform, exceptions
+from . import filesystem, tokens, platform, exceptions, expression
from .tokens import TokenType, is_string
@@ -8,7 +8,9 @@ class Tag(enum.Enum):
PRAGMA_ONCE = "#pragma_once"
IFDEF = "#ifdef"
IFNDEF = "#ifndef"
+ IF = "#if"
ELSE = "#else"
+ ELIF = "#elif"
def constants_to_token_constants(constants):
@@ -160,6 +162,53 @@ def process_undef(self, **kwargs):
del self.defines[undefine]
return
+ def process_if(self, **kwargs):
+ chunk = kwargs["chunk"]
+ line_no = kwargs["line_no"]
+ try:
+ result = expression.evaluate_expression(chunk, self.defines)
+ condition_met = result != 0
+ except (SyntaxError, ZeroDivisionError) as e:
+ fmt = "Error evaluating #if on line %s: %s"
+ raise exceptions.ParseError(fmt % (line_no, str(e)))
+
+ if not self.ignore and not condition_met:
+ self.ignore = True
+ self.constraints.append((Tag.IF, result, True, line_no))
+ else:
+ self.constraints.append((Tag.IF, result, False, line_no))
+
+ def process_elif(self, **kwargs):
+ chunk = kwargs["chunk"]
+ line_no = kwargs["line_no"]
+ if not self.constraints:
+ fmt = "Unexpected #elif on line %s"
+ raise exceptions.ParseError(fmt % line_no)
+
+ constraint_type, constraint, ignore, original_line_no = (
+ self.constraints.pop()
+ )
+
+ if constraint_type == Tag.ELSE:
+ fmt = "#elif after #else on line %s"
+ raise exceptions.ParseError(fmt % line_no)
+
+ try:
+ result = expression.evaluate_expression(chunk, self.defines)
+ condition_met = result != 0
+ except (SyntaxError, ZeroDivisionError) as e:
+ fmt = "Error evaluating #elif on line %s: %s"
+ raise exceptions.ParseError(fmt % (line_no, str(e)))
+
+ if self.ignore and ignore and condition_met:
+ ignore = False
+ self.ignore = False
+ elif not ignore:
+ ignore = True
+ self.ignore = True
+
+ self.constraints.append((Tag.ELIF, result, ignore, line_no))
+
def process_source_chunks(self, chunk):
if not self.ignore:
for token in self.token_expander.expand_tokens(chunk):
diff --git a/simplecpreprocessor/expression.py b/simplecpreprocessor/expression.py
new file mode 100644
index 0000000..fbaeb32
--- /dev/null
+++ b/simplecpreprocessor/expression.py
@@ -0,0 +1,260 @@
+"""
+Expression parser for C preprocessor #if and #elif directives.
+Uses a Pratt parser for operator precedence parsing.
+"""
+
+
+class ExpressionToken:
+ """Token for expression parsing."""
+ def __init__(self, type_, value):
+ self.type = type_
+ self.value = value
+
+ def __repr__(self):
+ return f"ExprToken({self.type}, {self.value!r})"
+
+
+class ExpressionLexer:
+ """Lexer for C preprocessor expressions."""
+
+ def __init__(self, tokens):
+ """
+ Initialize lexer with preprocessor tokens.
+
+ Args:
+ tokens: List of Token objects from the preprocessor
+ """
+ self.tokens = []
+ i = 0
+ non_ws_tokens = [t for t in tokens if not t.whitespace]
+
+ # Combine multi-character operators
+ while i < len(non_ws_tokens):
+ token = non_ws_tokens[i]
+
+ # Check for two-character operators
+ if i + 1 < len(non_ws_tokens):
+ next_token = non_ws_tokens[i + 1]
+ combined = token.value + next_token.value
+ if combined in ("&&", "||", "==", "!=", "<=", ">="):
+ # Create a combined token
+ from .tokens import Token, TokenType
+ combined_token = Token.from_string(
+ token.line_no, combined, TokenType.SYMBOL
+ )
+ self.tokens.append(combined_token)
+ i += 2
+ continue
+
+ self.tokens.append(token)
+ i += 1
+
+ self.pos = 0
+
+ def peek(self):
+ """Return current token without advancing."""
+ if self.pos < len(self.tokens):
+ return self.tokens[self.pos]
+ return None
+
+ def consume(self):
+ """Consume and return current token."""
+ token = self.peek()
+ self.pos += 1
+ return token
+
+ def at_end(self):
+ """Check if at end of tokens."""
+ return self.pos >= len(self.tokens)
+
+
+class ExpressionParser:
+ """
+ Pratt parser for C preprocessor constant expressions.
+ Supports: integers, defined(), logical ops, comparison, arithmetic.
+ """
+
+ def __init__(self, tokens, defines):
+ """
+ Initialize parser.
+
+ Args:
+ tokens: List of Token objects from preprocessor
+ defines: Defines object to check for macro definitions
+ """
+ self.lexer = ExpressionLexer(tokens)
+ self.defines = defines
+
+ def parse(self):
+ """Parse and evaluate the expression, returning an integer."""
+ if self.lexer.at_end():
+ return 0
+ result = self._parse_expr(0)
+ if not self.lexer.at_end():
+ raise SyntaxError(
+ f"Unexpected token: {self.lexer.peek().value}"
+ )
+ return result
+
+ def _parse_expr(self, min_precedence):
+ """Parse expression with precedence climbing."""
+ left = self._parse_primary()
+
+ while True:
+ token = self.lexer.peek()
+ if token is None:
+ break
+
+ op = token.value
+ # Stop at closing parenthesis
+ if op == ")":
+ break
+
+ precedence = self._get_precedence(op)
+ if precedence <= 0 or precedence < min_precedence:
+ break
+
+ self.lexer.consume()
+ right = self._parse_expr(precedence + 1)
+ left = self._apply_binary_op(op, left, right)
+
+ return left
+
+ def _parse_primary(self):
+ """Parse primary expression (numbers, defined, unary, parens)."""
+ token = self.lexer.peek()
+ if token is None:
+ raise SyntaxError("Unexpected end of expression")
+
+ # Handle parentheses
+ if token.value == "(":
+ self.lexer.consume()
+ result = self._parse_expr(0)
+ closing = self.lexer.peek()
+ if closing is None or closing.value != ")":
+ raise SyntaxError("Missing closing parenthesis")
+ self.lexer.consume()
+ return result
+
+ # Handle unary operators
+ if token.value in ("!", "+", "-"):
+ op = token.value
+ self.lexer.consume()
+ operand = self._parse_primary()
+ if op == "!":
+ return 0 if operand else 1
+ elif op == "-":
+ return -operand
+ else: # +
+ return operand
+
+ # Handle defined() operator
+ if token.value == "defined":
+ return self._parse_defined()
+
+ # Handle integer literals
+ try:
+ value = int(token.value)
+ self.lexer.consume()
+ return value
+ except ValueError:
+ # Undefined identifier evaluates to 0
+ self.lexer.consume()
+ return 0
+
+ def _parse_defined(self):
+ """Parse defined(MACRO) or defined MACRO."""
+ self.lexer.consume() # consume 'defined'
+
+ next_token = self.lexer.peek()
+ if next_token is None:
+ raise SyntaxError("Expected identifier after 'defined'")
+
+ has_parens = next_token.value == "("
+ if has_parens:
+ self.lexer.consume()
+ next_token = self.lexer.peek()
+ if next_token is None:
+ raise SyntaxError("Expected identifier in defined()")
+
+ macro_name = next_token.value
+ self.lexer.consume()
+
+ if has_parens:
+ closing = self.lexer.peek()
+ if closing is None or closing.value != ")":
+ raise SyntaxError("Missing closing paren in defined()")
+ self.lexer.consume()
+
+ return 1 if macro_name in self.defines else 0
+
+ def _get_precedence(self, op):
+ """Get operator precedence (higher = binds tighter)."""
+ precedence_table = {
+ "||": 1,
+ "&&": 2,
+ "|": 3,
+ "^": 4,
+ "&": 5,
+ "==": 6, "!=": 6,
+ "<": 7, ">": 7, "<=": 7, ">=": 7,
+ "+": 8, "-": 8,
+ "*": 9, "/": 9, "%": 9,
+ }
+ return precedence_table.get(op, 0)
+
+ def _apply_binary_op(self, op, left, right):
+ """Apply binary operator."""
+ if op == "||":
+ return 1 if (left or right) else 0
+ elif op == "&&":
+ return 1 if (left and right) else 0
+ elif op == "|":
+ return left | right
+ elif op == "^":
+ return left ^ right
+ elif op == "&":
+ return left & right
+ elif op == "==":
+ return 1 if left == right else 0
+ elif op == "!=":
+ return 1 if left != right else 0
+ elif op == "<":
+ return 1 if left < right else 0
+ elif op == ">":
+ return 1 if left > right else 0
+ elif op == "<=":
+ return 1 if left <= right else 0
+ elif op == ">=":
+ return 1 if left >= right else 0
+ elif op == "+":
+ return left + right
+ elif op == "-":
+ return left - right
+ elif op == "*":
+ return left * right
+ elif op == "/":
+ if right == 0:
+ raise ZeroDivisionError("Division by zero")
+ return left // right
+ elif op == "%":
+ if right == 0:
+ raise ZeroDivisionError("Modulo by zero")
+ return left % right
+ else:
+ raise SyntaxError(f"Unknown operator: {op}")
+
+
+def evaluate_expression(tokens, defines):
+ """
+ Evaluate a C preprocessor constant expression.
+
+ Args:
+ tokens: List of Token objects from the preprocessor
+ defines: Defines object to check for macro definitions
+
+ Returns:
+ Integer result of the expression (non-zero = true, 0 = false)
+ """
+ parser = ExpressionParser(tokens, defines)
+ return parser.parse()
diff --git a/simplecpreprocessor/tests/test_expression.py b/simplecpreprocessor/tests/test_expression.py
new file mode 100644
index 0000000..370052a
--- /dev/null
+++ b/simplecpreprocessor/tests/test_expression.py
@@ -0,0 +1,268 @@
+"""Tests for expression parser."""
+from __future__ import absolute_import
+import pytest
+from simplecpreprocessor.expression import evaluate_expression
+from simplecpreprocessor.core import Defines
+from simplecpreprocessor.tokens import Token, TokenType
+
+
+def make_tokens(values):
+ """Create Token objects from values."""
+ return [
+ Token.from_string(0, val, TokenType.IDENTIFIER)
+ for val in values
+ ]
+
+
+def test_simple_integer():
+ tokens = make_tokens(["42"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 42
+
+
+def test_simple_addition():
+ tokens = make_tokens(["1", "+", "2"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 3
+
+
+def test_simple_subtraction():
+ tokens = make_tokens(["5", "-", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 2
+
+
+def test_multiplication():
+ tokens = make_tokens(["3", "*", "4"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 12
+
+
+def test_division():
+ tokens = make_tokens(["10", "/", "2"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 5
+
+
+def test_modulo():
+ tokens = make_tokens(["10", "%", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_precedence_multiply_before_add():
+ tokens = make_tokens(["2", "+", "3", "*", "4"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 14
+
+
+def test_precedence_with_parentheses():
+ tokens = make_tokens(["(", "2", "+", "3", ")", "*", "4"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 20
+
+
+def test_logical_and_true():
+ tokens = make_tokens(["1", "&&", "1"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_logical_and_false():
+ tokens = make_tokens(["1", "&&", "0"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_logical_or_true():
+ tokens = make_tokens(["1", "||", "0"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_logical_or_false():
+ tokens = make_tokens(["0", "||", "0"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_logical_not_true():
+ tokens = make_tokens(["!", "0"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_logical_not_false():
+ tokens = make_tokens(["!", "1"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_equal():
+ tokens = make_tokens(["5", "==", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_not_equal():
+ tokens = make_tokens(["5", "!=", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_less_than():
+ tokens = make_tokens(["3", "<", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_greater_than():
+ tokens = make_tokens(["5", ">", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_less_than_or_equal():
+ tokens = make_tokens(["3", "<=", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_greater_than_or_equal():
+ tokens = make_tokens(["5", ">=", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_bitwise_and():
+ tokens = make_tokens(["5", "&", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_bitwise_or():
+ tokens = make_tokens(["4", "|", "2"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 6
+
+
+def test_bitwise_xor():
+ tokens = make_tokens(["5", "^", "3"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 6
+
+
+def test_unary_minus():
+ tokens = make_tokens(["-", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == -5
+
+
+def test_unary_plus():
+ tokens = make_tokens(["+", "5"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 5
+
+
+def test_defined_true():
+ tokens = make_tokens(["defined", "(", "FOO", ")"])
+ defines = Defines({"FOO": []})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_defined_false():
+ tokens = make_tokens(["defined", "(", "FOO", ")"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_defined_without_parens():
+ tokens = make_tokens(["defined", "FOO"])
+ defines = Defines({"FOO": []})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_defined_without_parens_false():
+ tokens = make_tokens(["defined", "BAR"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_complex_expression_with_defined():
+ tokens = make_tokens(
+ ["defined", "(", "FOO", ")", "&&", "(", "1", "+", "2", ")", ">", "2"]
+ )
+ defines = Defines({"FOO": []})
+ result = evaluate_expression(tokens, defines)
+ assert result == 1
+
+
+def test_undefined_identifier_evaluates_to_zero():
+ tokens = make_tokens(["UNDEFINED"])
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_empty_expression():
+ tokens = []
+ defines = Defines({})
+ result = evaluate_expression(tokens, defines)
+ assert result == 0
+
+
+def test_division_by_zero():
+ tokens = make_tokens(["1", "/", "0"])
+ defines = Defines({})
+ with pytest.raises(ZeroDivisionError):
+ evaluate_expression(tokens, defines)
+
+
+def test_modulo_by_zero():
+ tokens = make_tokens(["1", "%", "0"])
+ defines = Defines({})
+ with pytest.raises(ZeroDivisionError):
+ evaluate_expression(tokens, defines)
+
+
+def test_missing_closing_paren():
+ tokens = make_tokens(["(", "1", "+", "2"])
+ defines = Defines({})
+ with pytest.raises(SyntaxError):
+ evaluate_expression(tokens, defines)
+
+
+def test_missing_closing_paren_in_defined():
+ tokens = make_tokens(["defined", "(", "FOO"])
+ defines = Defines({})
+ with pytest.raises(SyntaxError):
+ evaluate_expression(tokens, defines)
diff --git a/simplecpreprocessor/tests/test_if_elif.py b/simplecpreprocessor/tests/test_if_elif.py
new file mode 100644
index 0000000..ae72665
--- /dev/null
+++ b/simplecpreprocessor/tests/test_if_elif.py
@@ -0,0 +1,356 @@
+"""Tests for #if and #elif directives."""
+from __future__ import absolute_import
+import pytest
+from simplecpreprocessor import preprocess
+from simplecpreprocessor.filesystem import FakeFile
+from simplecpreprocessor.exceptions import ParseError
+
+
+def run_case(input_list, expected):
+ ret = preprocess(input_list)
+ output = "".join(ret)
+ assert output == expected
+
+
+def test_if_true_simple():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_false_simple():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_if_with_expression():
+ f_obj = FakeFile("header.h", [
+ "#if 2 + 3\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_comparison_true():
+ f_obj = FakeFile("header.h", [
+ "#if 5 > 3\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_comparison_false():
+ f_obj = FakeFile("header.h", [
+ "#if 3 > 5\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_if_with_defined_true():
+ f_obj = FakeFile("header.h", [
+ "#define FOO\n",
+ "#if defined(FOO)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_defined_false():
+ f_obj = FakeFile("header.h", [
+ "#if defined(FOO)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_if_with_defined_no_parens():
+ f_obj = FakeFile("header.h", [
+ "#define BAR\n",
+ "#if defined BAR\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_logical_and_true():
+ f_obj = FakeFile("header.h", [
+ "#define A\n",
+ "#define B\n",
+ "#if defined(A) && defined(B)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_logical_and_false():
+ f_obj = FakeFile("header.h", [
+ "#define A\n",
+ "#if defined(A) && defined(B)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_if_with_logical_or_true():
+ f_obj = FakeFile("header.h", [
+ "#define A\n",
+ "#if defined(A) || defined(B)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_logical_not():
+ f_obj = FakeFile("header.h", [
+ "#if !defined(FOO)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_else_true():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "X\n",
+ "#else\n",
+ "Y\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_else_false():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "X\n",
+ "#else\n",
+ "Y\n",
+ "#endif\n"
+ ])
+ expected = "Y\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_first_true():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "A\n",
+ "#elif 1\n",
+ "B\n",
+ "#endif\n"
+ ])
+ expected = "A\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_second_true():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 1\n",
+ "B\n",
+ "#endif\n"
+ ])
+ expected = "B\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_all_false():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 0\n",
+ "B\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_elif_multiple():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 0\n",
+ "B\n",
+ "#elif 1\n",
+ "C\n",
+ "#endif\n"
+ ])
+ expected = "C\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_with_else():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 0\n",
+ "B\n",
+ "#else\n",
+ "C\n",
+ "#endif\n"
+ ])
+ expected = "C\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_with_defined():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif defined(FOO)\n",
+ "B\n",
+ "#else\n",
+ "C\n",
+ "#endif\n"
+ ])
+ expected = "C\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_with_defined_true():
+ f_obj = FakeFile("header.h", [
+ "#define FOO\n",
+ "#if 0\n",
+ "A\n",
+ "#elif defined(FOO)\n",
+ "B\n",
+ "#else\n",
+ "C\n",
+ "#endif\n"
+ ])
+ expected = "B\n"
+ run_case(f_obj, expected)
+
+
+def test_nested_if():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "#if 1\n",
+ "X\n",
+ "#endif\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_nested_if_outer_false():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "#if 1\n",
+ "X\n",
+ "#endif\n",
+ "#endif\n"
+ ])
+ expected = ""
+ run_case(f_obj, expected)
+
+
+def test_if_left_open_causes_error():
+ f_obj = FakeFile("header.h", ["#if 1\n"])
+ with pytest.raises(ParseError) as excinfo:
+ "".join(preprocess(f_obj))
+ s = str(excinfo.value)
+ assert "if" in s.lower()
+ assert "left open" in s
+
+
+def test_elif_without_if():
+ f_obj = FakeFile("header.h", ["#elif 1\n"])
+ with pytest.raises(ParseError) as excinfo:
+ "".join(preprocess(f_obj))
+ assert "Unexpected #elif" in str(excinfo.value)
+
+
+def test_elif_after_else():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "X\n",
+ "#else\n",
+ "Y\n",
+ "#elif 1\n",
+ "Z\n",
+ "#endif\n"
+ ])
+ with pytest.raises(ParseError) as excinfo:
+ "".join(preprocess(f_obj))
+ assert "#elif after #else" in str(excinfo.value)
+
+
+def test_if_with_parentheses():
+ f_obj = FakeFile("header.h", [
+ "#if (1 + 2) * 3\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_complex_expression():
+ f_obj = FakeFile("header.h", [
+ "#define A\n",
+ "#if defined(A) && (1 + 1 == 2)\n",
+ "X\n",
+ "#endif\n"
+ ])
+ expected = "X\n"
+ run_case(f_obj, expected)
+
+
+def test_if_with_define_expansion():
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "#define X value\n",
+ "#endif\n",
+ "X\n"
+ ])
+ expected = "value\n"
+ run_case(f_obj, expected)
+
+
+def test_elif_stops_at_first_true():
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 1\n",
+ "B\n",
+ "#elif 1\n",
+ "C\n",
+ "#endif\n"
+ ])
+ expected = "B\n"
+ run_case(f_obj, expected)
From b2589d0ecf5021f71ba496afdeee5fd3310b969a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 20:59:39 +0000
Subject: [PATCH 03/12] Update README to document #if and #elif support
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
README.md | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/README.md b/README.md
index 9640e15..c573cfe 100644
--- a/README.md
+++ b/README.md
@@ -14,9 +14,18 @@ behaviour.
Gotchas
---------
-Supported macros: ifdef, ifndef, define, undef, include, else,
+Supported macros: ifdef, ifndef, if, elif, define, undef, include, else,
pragma (only "once")
+The #if and #elif directives support constant expression evaluation including:
+ * Integer constants
+ * Arithmetic operators: +, -, *, /, %
+ * Comparison operators: ==, !=, <, >, <=, >=
+ * Logical operators: &&, ||, !
+ * Bitwise operators: &, |, ^
+ * The defined() operator (with or without parentheses)
+ * Parentheses for grouping
+
If using for FFI, you may want to ignore some system headers eg for types
Limitations:
From fa7e59043240055bff5ed574631c090ea1b3f286 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 21:03:53 +0000
Subject: [PATCH 04/12] Fix #elif and #else logic for if/elif chains
- Changed constraint field to track whether a branch was taken (boolean)
- Updated process_if to store branch_taken instead of expression result
- Updated process_elif to propagate branch_taken flag correctly
- Updated process_else to check branch_taken for IF/ELIF constraints
- All 139 tests pass with 96% coverage
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
simplecpreprocessor/core.py | 80 +++++++++++++++++++++++++++----------
1 file changed, 59 insertions(+), 21 deletions(-)
diff --git a/simplecpreprocessor/core.py b/simplecpreprocessor/core.py
index a4454a3..b40f64a 100644
--- a/simplecpreprocessor/core.py
+++ b/simplecpreprocessor/core.py
@@ -88,13 +88,30 @@ def process_else(self, **kwargs):
if not self.constraints:
fmt = "Unexpected #else on line %s"
raise exceptions.ParseError(fmt % line_no)
- _, constraint, ignore, _ = self.constraints.pop()
- if self.ignore and ignore:
- ignore = False
- self.ignore = False
- elif not self.ignore and not ignore:
- ignore = True
- self.ignore = True
+ constraint_type, constraint, ignore, _ = self.constraints.pop()
+
+ # For IF/ELIF, check if any branch was taken
+ if constraint_type in (Tag.IF, Tag.ELIF):
+ branch_was_taken = constraint
+ if branch_was_taken:
+ # A branch was already taken, don't take else
+ ignore = True
+ if not self.ignore:
+ self.ignore = True
+ else:
+ # No branch was taken, take the else
+ ignore = False
+ if self.ignore:
+ self.ignore = False
+ else:
+ # Original logic for IFDEF/IFNDEF
+ if self.ignore and ignore:
+ ignore = False
+ self.ignore = False
+ elif not self.ignore and not ignore:
+ ignore = True
+ self.ignore = True
+
self.constraints.append((Tag.ELSE, constraint, ignore, line_no))
def process_ifdef(self, **kwargs):
@@ -172,11 +189,13 @@ def process_if(self, **kwargs):
fmt = "Error evaluating #if on line %s: %s"
raise exceptions.ParseError(fmt % (line_no, str(e)))
+ # Store whether this branch was taken in the constraint field
+ branch_taken = condition_met
if not self.ignore and not condition_met:
self.ignore = True
- self.constraints.append((Tag.IF, result, True, line_no))
+ self.constraints.append((Tag.IF, branch_taken, True, line_no))
else:
- self.constraints.append((Tag.IF, result, False, line_no))
+ self.constraints.append((Tag.IF, branch_taken, False, line_no))
def process_elif(self, **kwargs):
chunk = kwargs["chunk"]
@@ -193,21 +212,40 @@ def process_elif(self, **kwargs):
fmt = "#elif after #else on line %s"
raise exceptions.ParseError(fmt % line_no)
- try:
- result = expression.evaluate_expression(chunk, self.defines)
- condition_met = result != 0
- except (SyntaxError, ZeroDivisionError) as e:
- fmt = "Error evaluating #elif on line %s: %s"
- raise exceptions.ParseError(fmt % (line_no, str(e)))
+ # Check if any previous branch was taken
+ # For IF/ELIF, constraint stores whether that branch was taken
+ previous_branch_taken = constraint if constraint_type in (
+ Tag.IF, Tag.ELIF
+ ) else (not ignore)
- if self.ignore and ignore and condition_met:
- ignore = False
- self.ignore = False
- elif not ignore:
+ if previous_branch_taken:
+ # A previous branch was taken, so ignore this elif
+ branch_taken = True # Mark that a branch was taken
ignore = True
- self.ignore = True
+ if not self.ignore:
+ self.ignore = True
+ else:
+ # No previous branch taken, evaluate this elif's condition
+ try:
+ result = expression.evaluate_expression(chunk, self.defines)
+ condition_met = result != 0
+ except (SyntaxError, ZeroDivisionError) as e:
+ fmt = "Error evaluating #elif on line %s: %s"
+ raise exceptions.ParseError(fmt % (line_no, str(e)))
+
+ if condition_met:
+ # This branch's condition is met
+ branch_taken = True
+ ignore = False
+ if self.ignore:
+ self.ignore = False
+ else:
+ # This branch's condition is not met
+ branch_taken = False
+ ignore = True
+ # self.ignore should already be True
- self.constraints.append((Tag.ELIF, result, ignore, line_no))
+ self.constraints.append((Tag.ELIF, branch_taken, ignore, line_no))
def process_source_chunks(self, chunk):
if not self.ignore:
From c746216680a0413be4f96eb00ee325449c18504d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 21:17:19 +0000
Subject: [PATCH 05/12] Refactor to stack-based condition frames for clearer
logic
- Replaced single self.ignore variable with condition_stack
- Created ConditionFrame class to track each conditional block
- Each frame tracks: tag, condition, line_no, branch_taken, currently_active
- Added _should_ignore() helper to check if content should be ignored
- Simplified all process_* methods to work with frames instead of constraints
- Logic is now more maintainable: each frame's state is explicit
- All 139 tests pass, 95% coverage maintained
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
simplecpreprocessor/core.py | 196 +++++++++++++++++++-----------------
1 file changed, 106 insertions(+), 90 deletions(-)
diff --git a/simplecpreprocessor/core.py b/simplecpreprocessor/core.py
index b40f64a..75725ab 100644
--- a/simplecpreprocessor/core.py
+++ b/simplecpreprocessor/core.py
@@ -40,6 +40,17 @@ def __contains__(self, key):
return key in self.defines
+class ConditionFrame:
+ """Represents a conditional compilation block (#if/#ifdef/#ifndef)."""
+
+ def __init__(self, tag, condition, line_no):
+ self.tag = tag
+ self.condition = condition
+ self.line_no = line_no
+ self.branch_taken = False
+ self.currently_active = False
+
+
class Preprocessor:
def __init__(self, line_ending=tokens.DEFAULT_LINE_ENDING,
@@ -49,8 +60,7 @@ def __init__(self, line_ending=tokens.DEFAULT_LINE_ENDING,
self.ignore_headers = ignore_headers
self.include_once = {}
self.defines = Defines(platform_constants)
- self.constraints = []
- self.ignore = False
+ self.condition_stack = []
self.line_ending = line_ending
self.last_constraint = None
self.header_stack = []
@@ -62,8 +72,15 @@ def __init__(self, line_ending=tokens.DEFAULT_LINE_ENDING,
self.headers = header_handler
self.headers.add_include_paths(include_paths)
+ def _should_ignore(self):
+ """Check if we should ignore content at the current nesting level."""
+ for frame in self.condition_stack:
+ if not frame.currently_active:
+ return True
+ return False
+
def process_define(self, **kwargs):
- if self.ignore:
+ if self._should_ignore():
return
chunk = kwargs["chunk"]
for i, tokenized in enumerate(chunk):
@@ -74,45 +91,33 @@ def process_define(self, **kwargs):
def process_endif(self, **kwargs):
line_no = kwargs["line_no"]
- if not self.constraints:
+ if not self.condition_stack:
fmt = "Unexpected #endif on line %s"
raise exceptions.ParseError(fmt % line_no)
- (constraint_type, constraint, ignore,
- original_line_no) = self.constraints.pop()
- if ignore:
- self.ignore = False
- self.last_constraint = constraint, constraint_type, original_line_no
+ frame = self.condition_stack.pop()
+ self.last_constraint = (
+ frame.condition, frame.tag, frame.line_no
+ )
def process_else(self, **kwargs):
line_no = kwargs["line_no"]
- if not self.constraints:
+ if not self.condition_stack:
fmt = "Unexpected #else on line %s"
raise exceptions.ParseError(fmt % line_no)
- constraint_type, constraint, ignore, _ = self.constraints.pop()
-
- # For IF/ELIF, check if any branch was taken
- if constraint_type in (Tag.IF, Tag.ELIF):
- branch_was_taken = constraint
- if branch_was_taken:
- # A branch was already taken, don't take else
- ignore = True
- if not self.ignore:
- self.ignore = True
- else:
- # No branch was taken, take the else
- ignore = False
- if self.ignore:
- self.ignore = False
+ frame = self.condition_stack[-1]
+
+ if frame.tag == Tag.ELSE:
+ fmt = "#else after #else on line %s"
+ raise exceptions.ParseError(fmt % line_no)
+
+ # Take the else branch only if no previous branch was taken
+ if not frame.branch_taken:
+ frame.currently_active = True
+ frame.branch_taken = True
else:
- # Original logic for IFDEF/IFNDEF
- if self.ignore and ignore:
- ignore = False
- self.ignore = False
- elif not self.ignore and not ignore:
- ignore = True
- self.ignore = True
+ frame.currently_active = False
- self.constraints.append((Tag.ELSE, constraint, ignore, line_no))
+ frame.tag = Tag.ELSE
def process_ifdef(self, **kwargs):
chunk = kwargs["chunk"]
@@ -121,11 +126,17 @@ def process_ifdef(self, **kwargs):
if not token.whitespace:
condition = token.value
break
- if not self.ignore and condition not in self.defines:
- self.ignore = True
- self.constraints.append((Tag.IFDEF, condition, True, line_no))
+
+ frame = ConditionFrame(Tag.IFDEF, condition, line_no)
+ parent_ignoring = self._should_ignore()
+
+ if not parent_ignoring and condition in self.defines:
+ frame.currently_active = True
+ frame.branch_taken = True
else:
- self.constraints.append((Tag.IFDEF, condition, False, line_no))
+ frame.currently_active = False
+
+ self.condition_stack.append(frame)
def process_pragma(self, **kwargs):
chunk = kwargs["chunk"]
@@ -165,11 +176,17 @@ def process_ifndef(self, **kwargs):
if not token.whitespace:
condition = token.value
break
- if not self.ignore and condition in self.defines:
- self.ignore = True
- self.constraints.append((Tag.IFNDEF, condition, True, line_no))
+
+ frame = ConditionFrame(Tag.IFNDEF, condition, line_no)
+ parent_ignoring = self._should_ignore()
+
+ if not parent_ignoring and condition not in self.defines:
+ frame.currently_active = True
+ frame.branch_taken = True
else:
- self.constraints.append((Tag.IFNDEF, condition, False, line_no))
+ frame.currently_active = False
+
+ self.condition_stack.append(frame)
def process_undef(self, **kwargs):
chunk = kwargs["chunk"]
@@ -189,66 +206,65 @@ def process_if(self, **kwargs):
fmt = "Error evaluating #if on line %s: %s"
raise exceptions.ParseError(fmt % (line_no, str(e)))
- # Store whether this branch was taken in the constraint field
- branch_taken = condition_met
- if not self.ignore and not condition_met:
- self.ignore = True
- self.constraints.append((Tag.IF, branch_taken, True, line_no))
+ frame = ConditionFrame(Tag.IF, result, line_no)
+ parent_ignoring = self._should_ignore()
+
+ if not parent_ignoring and condition_met:
+ frame.currently_active = True
+ frame.branch_taken = True
else:
- self.constraints.append((Tag.IF, branch_taken, False, line_no))
+ frame.currently_active = False
+
+ self.condition_stack.append(frame)
def process_elif(self, **kwargs):
chunk = kwargs["chunk"]
line_no = kwargs["line_no"]
- if not self.constraints:
+ if not self.condition_stack:
fmt = "Unexpected #elif on line %s"
raise exceptions.ParseError(fmt % line_no)
- constraint_type, constraint, ignore, original_line_no = (
- self.constraints.pop()
- )
+ frame = self.condition_stack[-1]
- if constraint_type == Tag.ELSE:
+ if frame.tag == Tag.ELSE:
fmt = "#elif after #else on line %s"
raise exceptions.ParseError(fmt % line_no)
- # Check if any previous branch was taken
- # For IF/ELIF, constraint stores whether that branch was taken
- previous_branch_taken = constraint if constraint_type in (
- Tag.IF, Tag.ELIF
- ) else (not ignore)
-
- if previous_branch_taken:
- # A previous branch was taken, so ignore this elif
- branch_taken = True # Mark that a branch was taken
- ignore = True
- if not self.ignore:
- self.ignore = True
+ # If a previous branch was taken, skip this elif
+ if frame.branch_taken:
+ frame.currently_active = False
+ frame.tag = Tag.ELIF
+ return
+
+ # No previous branch taken, evaluate this elif's condition
+ try:
+ result = expression.evaluate_expression(chunk, self.defines)
+ condition_met = result != 0
+ except (SyntaxError, ZeroDivisionError) as e:
+ fmt = "Error evaluating #elif on line %s: %s"
+ raise exceptions.ParseError(fmt % (line_no, str(e)))
+
+ parent_ignoring = self._should_ignore_at_level(
+ len(self.condition_stack) - 1
+ )
+
+ if not parent_ignoring and condition_met:
+ frame.currently_active = True
+ frame.branch_taken = True
else:
- # No previous branch taken, evaluate this elif's condition
- try:
- result = expression.evaluate_expression(chunk, self.defines)
- condition_met = result != 0
- except (SyntaxError, ZeroDivisionError) as e:
- fmt = "Error evaluating #elif on line %s: %s"
- raise exceptions.ParseError(fmt % (line_no, str(e)))
-
- if condition_met:
- # This branch's condition is met
- branch_taken = True
- ignore = False
- if self.ignore:
- self.ignore = False
- else:
- # This branch's condition is not met
- branch_taken = False
- ignore = True
- # self.ignore should already be True
+ frame.currently_active = False
+
+ frame.tag = Tag.ELIF
- self.constraints.append((Tag.ELIF, branch_taken, ignore, line_no))
+ def _should_ignore_at_level(self, level):
+ """Check if we should ignore at a specific stack level."""
+ for i in range(level):
+ if not self.condition_stack[i].currently_active:
+ return True
+ return False
def process_source_chunks(self, chunk):
- if not self.ignore:
+ if not self._should_ignore():
for token in self.token_expander.expand_tokens(chunk):
if self.fold_strings_to_null and is_string(token):
yield "NULL"
@@ -390,14 +406,14 @@ def preprocess(self, f_object, depth=0):
yield token
self.check_fullfile_guard()
self.header_stack.pop()
- if not self.header_stack and self.constraints:
- constraint_type, name, _, line_no = self.constraints[-1]
+ if not self.header_stack and self.condition_stack:
+ frame = self.condition_stack[-1]
fmt = (
"{tag} {name} from line {line_no} left open"
.format(
- tag=constraint_type.value,
- name=name,
- line_no=line_no
+ tag=frame.tag.value,
+ name=frame.condition,
+ line_no=frame.line_no
)
)
raise exceptions.ParseError(fmt)
From fbb2e8e890ce348747efe46158a2cc320e4f0f02 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 21:28:11 +0000
Subject: [PATCH 06/12] Use walrus operator in expression parser loop
Applied walrus operator (:=) in _parse_expr to combine token assignment
and None check as suggested in code review. Changed from:
while True: token = self.lexer.peek(); if token is None: break
To:
while (token := self.lexer.peek()) is not None:
All 139 tests pass, linting clean.
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
simplecpreprocessor/expression.py | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/simplecpreprocessor/expression.py b/simplecpreprocessor/expression.py
index fbaeb32..b997dce 100644
--- a/simplecpreprocessor/expression.py
+++ b/simplecpreprocessor/expression.py
@@ -100,11 +100,7 @@ def _parse_expr(self, min_precedence):
"""Parse expression with precedence climbing."""
left = self._parse_primary()
- while True:
- token = self.lexer.peek()
- if token is None:
- break
-
+ while (token := self.lexer.peek()) is not None:
op = token.value
# Stop at closing parenthesis
if op == ")":
From 40efbbc614cd1e5ee500644090e37b01d6ddd005 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 21:40:43 +0000
Subject: [PATCH 07/12] Add codecov.yml and update coverage documentation
- Created codecov.yml to ensure consistent coverage reporting between local
and CI/codecov
- Configured codecov to ignore same files as .coveragerc
- Set thresholds and precision to match local settings
- Updated CONTRIBUTING.md to document the exact CI coverage command including
XML report generation
- Both local and codecov now use: py.test -v --cov=simplecpreprocessor
--cov-config .coveragerc --cov-report=xml --cov-report=term-missing
- This ensures coverage numbers are consistent across environments
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
CONTRIBUTING.md | 6 +-
codecov.yml | 28 ++
coverage.xml | 695 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 727 insertions(+), 2 deletions(-)
create mode 100644 codecov.yml
create mode 100644 coverage.xml
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c0a1ab1..a368303 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -42,10 +42,12 @@ All contributions must pass linting with no errors.
Run tests with coverage (matches CI):
```bash
- py.test -v --cov=simplecpreprocessor --cov-config .coveragerc --cov-report=term-missing
+py.test -v --cov=simplecpreprocessor --cov-config .coveragerc --cov-report=xml --cov-report=term-missing
```
-Coverage must remain at or above the current threshold. Coverage reports are generated automatically in CI.
+This generates both a terminal report and an XML report (`coverage.xml`) that codecov uses.
+
+Coverage must remain at or above the current threshold. Coverage reports are generated automatically in CI and uploaded to codecov.
## Pull requests
diff --git a/codecov.yml b/codecov.yml
new file mode 100644
index 0000000..2723539
--- /dev/null
+++ b/codecov.yml
@@ -0,0 +1,28 @@
+codecov:
+ require_ci_to_pass: true
+
+coverage:
+ precision: 2
+ round: down
+ range: "90...100"
+
+ status:
+ project:
+ default:
+ target: auto
+ threshold: 0.5%
+ patch:
+ default:
+ target: auto
+ threshold: 0.5%
+
+ignore:
+ - "simplecpreprocessor/__init__.py"
+ - "simplecpreprocessor/__main__.py"
+ - "simplecpreprocessor/tests"
+ - "simplecpreprocessor/tests/*.py"
+
+comment:
+ layout: "reach,diff,flags,tree"
+ behavior: default
+ require_changes: false
diff --git a/coverage.xml b/coverage.xml
new file mode 100644
index 0000000..ca5cf9d
--- /dev/null
+++ b/coverage.xml
@@ -0,0 +1,695 @@
+
+
+
+
+
+ /home/runner/work/simplecpreprocessor/simplecpreprocessor/simplecpreprocessor
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
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From d5d03966c3e168b94628a90daea1ce2178f685b7 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 21:41:14 +0000
Subject: [PATCH 08/12] Add coverage.xml to .gitignore
Removed coverage.xml from repository as it's a generated artifact. Added it
to .gitignore to prevent accidental commits in the future.
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
.gitignore | 1 +
coverage.xml | 695 ---------------------------------------------------
2 files changed, 1 insertion(+), 695 deletions(-)
delete mode 100644 coverage.xml
diff --git a/.gitignore b/.gitignore
index 2e9253a..1ef5456 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
*.pyc
.coverage
+coverage.xml
dist
htmlcov
.venv
diff --git a/coverage.xml b/coverage.xml
deleted file mode 100644
index ca5cf9d..0000000
--- a/coverage.xml
+++ /dev/null
@@ -1,695 +0,0 @@
-
-
-
-
-
- /home/runner/work/simplecpreprocessor/simplecpreprocessor/simplecpreprocessor
-
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From 4069aa49b4ee7f3ced8f0e02b321cb1f0c72d704 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 22:03:41 +0000
Subject: [PATCH 09/12] Improve test coverage to 98% with comprehensive edge
case tests
- Added 10 new tests for expression parser edge cases (now 100% coverage)
- Added tests for #if/#elif error handling (invalid expressions)
- Added test for #else after #else error case
- Added pragma: no cover to defensive but impossible cases in core.py
- ExpressionToken class now fully tested (repr and attributes)
- All error paths in expression parser now covered
- Coverage improved from 95% to 98% overall
- expression.py: 94% -> 100% coverage
- core.py: 94% -> 97% coverage
- All 149 tests pass, flake8 clean
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
simplecpreprocessor/core.py | 26 +++++--
simplecpreprocessor/expression.py | 2 +-
simplecpreprocessor/tests/test_expression.py | 73 ++++++++++++++++++++
simplecpreprocessor/tests/test_if_elif.py | 40 +++++++++++
4 files changed, 136 insertions(+), 5 deletions(-)
diff --git a/simplecpreprocessor/core.py b/simplecpreprocessor/core.py
index 75725ab..fb2ffe9 100644
--- a/simplecpreprocessor/core.py
+++ b/simplecpreprocessor/core.py
@@ -87,6 +87,9 @@ def process_define(self, **kwargs):
if not tokenized.whitespace:
define_name = tokenized.value
break
+ else: # pragma: no cover
+ # Defensive: should never happen as tokenizer ensures non-ws tokens
+ return
self.defines[define_name] = chunk[i+2:-1]
def process_endif(self, **kwargs):
@@ -122,11 +125,16 @@ def process_else(self, **kwargs):
def process_ifdef(self, **kwargs):
chunk = kwargs["chunk"]
line_no = kwargs["line_no"]
+ condition = None
for token in chunk:
if not token.whitespace:
condition = token.value
break
+ if condition is None: # pragma: no cover
+ # Defensive: should never happen as tokenizer ensures non-ws tokens
+ return
+
frame = ConditionFrame(Tag.IFDEF, condition, line_no)
parent_ignoring = self._should_ignore()
@@ -142,16 +150,21 @@ def process_pragma(self, **kwargs):
chunk = kwargs["chunk"]
line_no = kwargs["line_no"]
pragma = None
+ token = None
for token in chunk:
if not token.whitespace:
method_name = "process_pragma_%s" % token.value
pragma = getattr(self, method_name, None)
break
if pragma is None:
- s = (
- "Unsupported pragma %s on line %s"
- % (token.value, line_no)
- )
+ if token is None: # pragma: no cover
+ # Defensive: should never happen
+ s = "Unsupported pragma on line %s" % line_no
+ else:
+ s = (
+ "Unsupported pragma %s on line %s"
+ % (token.value, line_no)
+ )
raise exceptions.ParseError(s)
else:
ret = pragma(chunk=chunk, line_no=line_no)
@@ -172,11 +185,16 @@ def current_name(self):
def process_ifndef(self, **kwargs):
chunk = kwargs["chunk"]
line_no = kwargs["line_no"]
+ condition = None
for token in chunk:
if not token.whitespace:
condition = token.value
break
+ if condition is None: # pragma: no cover
+ # Defensive: should never happen as tokenizer ensures non-ws tokens
+ return
+
frame = ConditionFrame(Tag.IFNDEF, condition, line_no)
parent_ignoring = self._should_ignore()
diff --git a/simplecpreprocessor/expression.py b/simplecpreprocessor/expression.py
index b997dce..b9b8c30 100644
--- a/simplecpreprocessor/expression.py
+++ b/simplecpreprocessor/expression.py
@@ -237,7 +237,7 @@ def _apply_binary_op(self, op, left, right):
if right == 0:
raise ZeroDivisionError("Modulo by zero")
return left % right
- else:
+ else: # pragma: no cover
raise SyntaxError(f"Unknown operator: {op}")
diff --git a/simplecpreprocessor/tests/test_expression.py b/simplecpreprocessor/tests/test_expression.py
index 370052a..40c0c48 100644
--- a/simplecpreprocessor/tests/test_expression.py
+++ b/simplecpreprocessor/tests/test_expression.py
@@ -266,3 +266,76 @@ def test_missing_closing_paren_in_defined():
defines = Defines({})
with pytest.raises(SyntaxError):
evaluate_expression(tokens, defines)
+
+
+def test_unexpected_token_after_expression():
+ """Test that extra tokens after a complete expression raise an error."""
+ tokens = make_tokens(["1", "+", "2", "extra"])
+ defines = Defines({})
+ with pytest.raises(SyntaxError, match="Unexpected token"):
+ evaluate_expression(tokens, defines)
+
+
+def test_unexpected_end_in_parse_primary():
+ """Test parse_primary when token stream ends unexpectedly."""
+ # This tests the case where we're in the middle of parsing and run out
+ # Creating an expression that consumes all tokens in _parse_primary
+ tokens = make_tokens(["1", "+"])
+ defines = Defines({})
+ with pytest.raises(SyntaxError, match="Unexpected end of expression"):
+ evaluate_expression(tokens, defines)
+
+
+def test_defined_without_identifier():
+ """Test defined() with no identifier following."""
+ # Create tokens: just "defined" with nothing after
+ tokens = [Token.from_string(0, "defined", TokenType.IDENTIFIER)]
+ defines = Defines({})
+ with pytest.raises(SyntaxError, match="Expected identifier after"):
+ evaluate_expression(tokens, defines)
+
+
+def test_defined_with_parens_no_identifier():
+ """Test defined( with no identifier inside parentheses."""
+ # Create tokens: "defined" "(" ")" - this will use ")" as identifier
+ # and then fail to find closing paren
+ tokens = [
+ Token.from_string(0, "defined", TokenType.IDENTIFIER),
+ Token.from_string(0, "(", TokenType.SYMBOL),
+ Token.from_string(0, ")", TokenType.SYMBOL)
+ ]
+ defines = Defines({})
+ with pytest.raises(SyntaxError, match="Missing closing paren"):
+ evaluate_expression(tokens, defines)
+
+
+def test_defined_with_parens_truncated():
+ """Test defined( with token stream ending."""
+ # This tests line 174 - when we have "defined (" but no more tokens
+ from simplecpreprocessor.tokens import Token, TokenType
+
+ # Manually create scenario where after "defined (", no more tokens
+ tokens = [
+ Token.from_string(0, "defined", TokenType.IDENTIFIER),
+ Token.from_string(0, "(", TokenType.SYMBOL)
+ ]
+ defines = Defines({})
+ with pytest.raises(SyntaxError, match="Expected identifier in defined"):
+ evaluate_expression(tokens, defines)
+
+
+def test_expression_token_repr():
+ """Test ExpressionToken __repr__ for coverage."""
+ from simplecpreprocessor.expression import ExpressionToken
+ token = ExpressionToken("NUMBER", "42")
+ assert "ExprToken" in repr(token)
+ assert "NUMBER" in repr(token)
+ assert "42" in repr(token)
+
+
+def test_expression_token_attributes():
+ """Test ExpressionToken attributes for coverage."""
+ from simplecpreprocessor.expression import ExpressionToken
+ token = ExpressionToken("NUMBER", "42")
+ assert token.type == "NUMBER"
+ assert token.value == "42"
diff --git a/simplecpreprocessor/tests/test_if_elif.py b/simplecpreprocessor/tests/test_if_elif.py
index ae72665..1a86c88 100644
--- a/simplecpreprocessor/tests/test_if_elif.py
+++ b/simplecpreprocessor/tests/test_if_elif.py
@@ -310,6 +310,22 @@ def test_elif_after_else():
assert "#elif after #else" in str(excinfo.value)
+def test_else_after_else():
+ """Test that #else after #else raises an error."""
+ f_obj = FakeFile("header.h", [
+ "#if 1\n",
+ "X\n",
+ "#else\n",
+ "Y\n",
+ "#else\n",
+ "Z\n",
+ "#endif\n"
+ ])
+ with pytest.raises(ParseError) as excinfo:
+ "".join(preprocess(f_obj))
+ assert "#else after #else" in str(excinfo.value)
+
+
def test_if_with_parentheses():
f_obj = FakeFile("header.h", [
"#if (1 + 2) * 3\n",
@@ -354,3 +370,27 @@ def test_elif_stops_at_first_true():
])
expected = "B\n"
run_case(f_obj, expected)
+
+
+def test_if_with_invalid_expression():
+ """Test #if with syntax error in expression."""
+ f_obj = FakeFile("header.h", [
+ "#if 1 (\n",
+ "X\n",
+ "#endif\n"
+ ])
+ with pytest.raises(ParseError, match="Error evaluating #if"):
+ "".join(preprocess(f_obj))
+
+
+def test_elif_with_invalid_expression():
+ """Test #elif with syntax error in expression."""
+ f_obj = FakeFile("header.h", [
+ "#if 0\n",
+ "A\n",
+ "#elif 1 / 0\n",
+ "B\n",
+ "#endif\n"
+ ])
+ with pytest.raises(ParseError, match="Error evaluating #elif"):
+ "".join(preprocess(f_obj))
From 66694c31f66a47f162e849ebe83dfe2cf418fc83 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 22:21:58 +0000
Subject: [PATCH 10/12] Fix codecov path mapping issue with relative_files
option
- Added relative_files = True to .coveragerc [run] section
- This ensures coverage.xml uses relative paths instead of absolute paths
- Changed source path from absolute to relative: simplecpreprocessor
- Updated codecov.yml with fixes directive for path normalization
- This fixes codecov's inability to detect coverage due to path mismatch
- All 149 tests pass, 98% coverage maintained
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
.coveragerc | 4 ++++
codecov.yml | 3 +++
2 files changed, 7 insertions(+)
diff --git a/.coveragerc b/.coveragerc
index 5709624..d1fc3a6 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,6 +1,10 @@
[run]
branch = True
+relative_files = True
omit =
simplecpreprocessor/__init__.py
simplecpreprocessor/__main__.py
simplecpreprocessor/tests/*.py
+
+[xml]
+output = coverage.xml
diff --git a/codecov.yml b/codecov.yml
index 2723539..c4d6cbc 100644
--- a/codecov.yml
+++ b/codecov.yml
@@ -16,6 +16,9 @@ coverage:
target: auto
threshold: 0.5%
+fixes:
+ - "simplecpreprocessor/::"
+
ignore:
- "simplecpreprocessor/__init__.py"
- "simplecpreprocessor/__main__.py"
From bad0b0e281782a567f003745d8efd2b99253b311 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 22:32:55 +0000
Subject: [PATCH 11/12] Fix codecov workflow configuration with root_dir
- Removed incorrect 'fixes' directive from codecov.yml
- Added root_dir parameter to codecov action in workflow
- This ensures codecov can correctly map file paths in coverage.xml to
repository files
- The workflow now explicitly sets the workspace root for codecov
- All 149 tests pass, 98% coverage maintained
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
.github/workflows/ci-build.yml | 1 +
codecov.yml | 3 ---
2 files changed, 1 insertion(+), 3 deletions(-)
diff --git a/.github/workflows/ci-build.yml b/.github/workflows/ci-build.yml
index 4ae43d4..ec16b90 100644
--- a/.github/workflows/ci-build.yml
+++ b/.github/workflows/ci-build.yml
@@ -74,3 +74,4 @@ jobs:
use_oidc: true
fail_ci_if_error: true
verbose: true
+ root_dir: ${{ github.workspace }}
diff --git a/codecov.yml b/codecov.yml
index c4d6cbc..2723539 100644
--- a/codecov.yml
+++ b/codecov.yml
@@ -16,9 +16,6 @@ coverage:
target: auto
threshold: 0.5%
-fixes:
- - "simplecpreprocessor/::"
-
ignore:
- "simplecpreprocessor/__init__.py"
- "simplecpreprocessor/__main__.py"
From cbd141179b1b82629d30996442f8cea1f9b710b9 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 18 Feb 2026 23:03:17 +0000
Subject: [PATCH 12/12] Restructure CI workflow to run coverage tests in upload
job
- Removed artifact upload/download mechanism that was causing issues
- Regular test job now runs tests without coverage (faster)
- upload-coverage job runs tests with coverage and uploads directly to codecov
- This avoids file path issues from artifact download
- coverage.xml is generated in the same workspace where codecov runs
- Removed root_dir parameter as it's no longer needed
- All 149 tests pass, 98% coverage maintained
Co-authored-by: nanonyme <348449+nanonyme@users.noreply.github.com>
---
.github/workflows/ci-build.yml | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/.github/workflows/ci-build.yml b/.github/workflows/ci-build.yml
index ec16b90..2e4362f 100644
--- a/.github/workflows/ci-build.yml
+++ b/.github/workflows/ci-build.yml
@@ -35,7 +35,7 @@ jobs:
flake8 simplecpreprocessor
test:
- name: Test with coverage
+ name: Run tests
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4.1.7
@@ -43,17 +43,10 @@ jobs:
- uses: ./.github/actions/prepare-build
- run: |
- py.test -v --cov=simplecpreprocessor --cov-config .coveragerc --cov-report=xml --cov-report=term-missing
-
- - name: Upload coverage artifact
- uses: actions/upload-artifact@v4.3.3
- with:
- name: coverage
- path: coverage.xml
+ py.test -v
upload-coverage:
- name: Publish coverage report
- needs: test
+ name: Test with coverage and publish report
# Disabled for fork PR's as we can't use OIDC there
if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name == github.repository
runs-on: ubuntu-latest
@@ -63,9 +56,11 @@ jobs:
steps:
- uses: actions/checkout@v4.1.7
- - uses: actions/download-artifact@v4.1.8
- with:
- name: coverage
+ - uses: ./.github/actions/prepare-build
+
+ - name: Run tests with coverage
+ run: |
+ py.test -v --cov=simplecpreprocessor --cov-config .coveragerc --cov-report=xml --cov-report=term-missing
- name: Upload to Codecov via OIDC
uses: codecov/codecov-action@v5.5.0
@@ -74,4 +69,3 @@ jobs:
use_oidc: true
fail_ci_if_error: true
verbose: true
- root_dir: ${{ github.workspace }}