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use syn::spanned::Spanned;
use syn::visit::Visit;
use syn::{Expr, ExprCall, ExprMethodCall};
use super::{is_delegation_only_body, is_match_dispatch, is_trivial_match_arm, BodyVisitor};
use crate::analyzer::types::CallOccurrence;
impl<'a, 'ast> Visit<'ast> for BodyVisitor<'a> {
fn visit_expr(&mut self, expr: &'ast Expr) {
// Reset boolean alternation tracking for non-boolean expressions
if !matches!(expr, Expr::Binary(b) if matches!(b.op, syn::BinOp::And(_) | syn::BinOp::Or(_)))
{
self.last_boolean_op = None;
}
match expr {
// --- Logic detection ---
Expr::If(expr_if) => {
// Complexity: always tracked (regardless of closure leniency)
self.cognitive_complexity += 1 + self.nesting_depth;
self.cyclomatic_complexity += 1;
self.record_hotspot("if", expr_if.if_token.span);
// IOSP: respects closure leniency
self.record_logic("if", expr_if.if_token.span);
self.enter_nesting();
syn::visit::visit_expr(self, expr);
self.exit_nesting();
return;
}
Expr::Match(expr_match) => {
self.cognitive_complexity += 1 + self.nesting_depth;
// Cyclomatic: only non-trivial arms count (trivial lookup arms excluded)
let non_trivial = expr_match
.arms
.iter()
.filter(|arm| !is_trivial_match_arm(arm))
.count();
self.cyclomatic_complexity += non_trivial.saturating_sub(1);
self.record_hotspot("match", expr_match.match_token.span);
if !is_match_dispatch(&expr_match.arms) {
self.record_logic("match", expr_match.match_token.span);
}
self.enter_nesting();
syn::visit::visit_expr(self, expr);
self.exit_nesting();
return;
}
Expr::ForLoop(expr_for) => {
self.cognitive_complexity += 1 + self.nesting_depth;
self.cyclomatic_complexity += 1;
self.record_hotspot("for", expr_for.for_token.span);
if !is_delegation_only_body(&expr_for.body.stmts) {
self.record_logic("for", expr_for.for_token.span);
}
// Skip logic detection in the iterator expression (range, .len(), etc.)
self.in_for_iter = true;
self.visit_expr(&expr_for.expr);
self.in_for_iter = false;
self.visit_pat(&expr_for.pat);
self.enter_nesting();
self.visit_block(&expr_for.body);
self.exit_nesting();
return;
}
Expr::While(expr_while) => {
self.cognitive_complexity += 1 + self.nesting_depth;
self.cyclomatic_complexity += 1;
self.record_hotspot("while", expr_while.while_token.span);
self.record_logic("while", expr_while.while_token.span);
self.enter_nesting();
syn::visit::visit_expr(self, expr);
self.exit_nesting();
return;
}
Expr::Loop(expr_loop) => {
self.cognitive_complexity += 1 + self.nesting_depth;
self.cyclomatic_complexity += 1;
self.record_hotspot("loop", expr_loop.loop_token.span);
self.record_logic("loop", expr_loop.loop_token.span);
self.enter_nesting();
syn::visit::visit_expr(self, expr);
self.exit_nesting();
return;
}
// --- ? operator as logic (when strict_error_propagation enabled) ---
Expr::Try(expr_try) => {
if self.config.strict_error_propagation {
self.record_logic("?", expr_try.question_token.span());
}
syn::visit::visit_expr(self, expr);
return;
}
// --- Arithmetic / boolean operators as logic ---
Expr::Binary(expr_bin) => {
use syn::BinOp;
let kind = match &expr_bin.op {
BinOp::Add(_)
| BinOp::Sub(_)
| BinOp::Mul(_)
| BinOp::Div(_)
| BinOp::Rem(_) => Some("arithmetic"),
BinOp::And(_) | BinOp::Or(_) => Some("boolean_op"),
BinOp::Eq(_)
| BinOp::Ne(_)
| BinOp::Lt(_)
| BinOp::Le(_)
| BinOp::Gt(_)
| BinOp::Ge(_) => Some("comparison"),
BinOp::BitAnd(_)
| BinOp::BitOr(_)
| BinOp::BitXor(_)
| BinOp::Shl(_)
| BinOp::Shr(_) => Some("bitwise"),
_ => None,
};
if let Some(kind) = kind {
self.record_logic(kind, expr_bin.op.span());
}
// Complexity: boolean operators add to cyclomatic and track alternation
match &expr_bin.op {
BinOp::And(_) => {
self.cyclomatic_complexity += 1;
let is_and = true;
if let Some(last) = self.last_boolean_op {
if last != is_and {
self.cognitive_complexity += 1;
}
}
self.last_boolean_op = Some(is_and);
}
BinOp::Or(_) => {
self.cyclomatic_complexity += 1;
let is_and = false;
if let Some(last) = self.last_boolean_op {
if last != is_and {
self.cognitive_complexity += 1;
}
}
self.last_boolean_op = Some(is_and);
}
_ => {}
}
syn::visit::visit_expr(self, expr);
return;
}
// --- Unsafe blocks: count occurrences ---
Expr::Unsafe(_) => {
self.unsafe_block_count += 1;
syn::visit::visit_expr(self, expr);
return;
}
// --- Closures: track depth ---
Expr::Closure(_) => {
self.closure_depth += 1;
syn::visit::visit_expr(self, expr);
self.closure_depth -= 1;
return;
}
// --- Async blocks: track depth (treated like closures) ---
Expr::Async(_) => {
self.async_block_depth += 1;
syn::visit::visit_expr(self, expr);
self.async_block_depth -= 1;
return;
}
// --- .await is not logic ---
Expr::Await(_) => {
syn::visit::visit_expr(self, expr);
return;
}
// --- Array index: skip magic number detection for index expression ---
Expr::Index(expr_index) => {
self.visit_expr(&expr_index.expr);
self.in_index_context += 1;
self.visit_expr(&expr_index.index);
self.in_index_context -= 1;
return;
}
// --- Numeric literals: magic number detection ---
Expr::Lit(expr_lit) => {
match &expr_lit.lit {
syn::Lit::Int(lit_int) => {
self.record_magic_number(
lit_int.base10_digits().to_string(),
lit_int.span(),
);
}
syn::Lit::Float(lit_float) => {
self.record_magic_number(
lit_float.base10_digits().to_string(),
lit_float.span(),
);
}
_ => {}
}
syn::visit::visit_expr(self, expr);
return;
}
// --- Unary negation: detect negative magic numbers like -1 ---
// Handle as a unit to avoid double-counting the inner positive literal.
Expr::Unary(expr_unary) if matches!(expr_unary.op, syn::UnOp::Neg(_)) => {
if let Expr::Lit(expr_lit) = &*expr_unary.expr {
match &expr_lit.lit {
syn::Lit::Int(lit_int) => {
self.record_magic_number(
format!("-{}", lit_int.base10_digits()),
lit_int.span(),
);
// Skip default recursion — we already handled the inner literal
return;
}
syn::Lit::Float(lit_float) => {
self.record_magic_number(
format!("-{}", lit_float.base10_digits()),
lit_float.span(),
);
return;
}
_ => {}
}
}
syn::visit::visit_expr(self, expr);
return;
}
// --- Macro detection for error handling: panic!/todo!/unreachable! ---
Expr::Macro(expr_macro) => {
let macro_name = expr_macro
.mac
.path
.segments
.last()
.map(|s| s.ident.to_string());
match macro_name.as_deref() {
Some("panic") => self.panic_count += 1,
Some("unreachable") => self.panic_count += 1,
Some("todo") => self.todo_count += 1,
_ => {}
}
syn::visit::visit_expr(self, expr);
return;
}
// --- Function call detection ---
Expr::Call(ExprCall { func, .. }) => {
if self.in_lenient_nested_context() {
// skip in lenient closure/async mode
} else if let Some(name) = Self::extract_call_name(func) {
if self.config.allow_recursion && self.is_recursive_call(&name) {
// Recursive call — skip when allow_recursion is enabled
} else if self.scope.is_own_function(&name) {
self.own_calls.push(CallOccurrence {
name,
line: func.span().start().line,
});
}
}
syn::visit::visit_expr(self, expr);
return;
}
Expr::MethodCall(ExprMethodCall {
method, receiver, ..
}) => {
let method_name = method.to_string();
// Error handling: count in ALL contexts (including closures)
match method_name.as_str() {
"unwrap" => self.unwrap_count += 1,
"expect" => self.expect_count += 1,
_ => {}
}
if self.in_lenient_nested_context() {
// skip in lenient closure/async mode
} else {
let is_iterator = Self::is_iterator_method(&method_name);
if is_iterator && !self.config.strict_iterator_chains {
// skip — iterator adaptor, not an "own call"
} else if self.config.allow_recursion && self.is_recursive_call(&method_name) {
// Recursive call — skip
} else if self.is_type_resolved_own_method(&method_name, receiver) {
self.own_calls.push(CallOccurrence {
name: format!(".{method_name}()"),
line: method.span().start().line,
});
}
}
syn::visit::visit_expr(self, expr);
return;
}
_ => {}
}
// Default: recurse into children
syn::visit::visit_expr(self, expr);
}
/// Track const item context to suppress magic number detection.
fn visit_item_const(&mut self, i: &'ast syn::ItemConst) {
self.in_const_context += 1;
syn::visit::visit_item_const(self, i);
self.in_const_context -= 1;
}
/// Track static item context to suppress magic number detection.
fn visit_item_static(&mut self, i: &'ast syn::ItemStatic) {
self.in_const_context += 1;
syn::visit::visit_item_static(self, i);
self.in_const_context -= 1;
}
}