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#![allow(
clippy::enum_glob_use,
clippy::too_many_lines,
clippy::wildcard_imports
)]
#![allow(
clippy::cast_precision_loss,
clippy::cast_possible_truncation,
clippy::cast_sign_loss
)]
use super::{Abc, Stats};
use crate::*;
impl Abc for BashCode {
fn compute<'a>(
node: &Node<'a>,
code: &'a [u8],
ancestors: Ancestors<'a, '_>,
stats: &mut Stats,
) {
match node.kind_id().into() {
// Each `variable_assignment` is one assignment regardless of
// operator (`=`, `+=`, `-=`, …) — counting the parent node
// avoids double-counting `Bash::EQ`, which is also produced
// for the `=` inside `[ a = b ]` test expressions.
Bash::VariableAssignment | Bash::VariableAssignment2 => {
stats.assignments += 1.;
}
// Every command invocation is a branch in the ABC sense
// (function-call / message-pass). `return` and `exit` builtins
// are also `Bash::Command` nodes and count here too.
Bash::Command => {
stats.branches += 1.;
}
// Three condition signals share this arm:
//
// - Comparison operators inside `[[ … ]]` and `(( … ))`, plus
// the prefix test operators `-z`, `-n`, `-eq`, `-lt`, … which
// the grammar emits as `Bash::TestOperator`.
// - Control-flow branches (`if`/`elif`/`while`). A Bash predicate
// is a command, so the branch keyword itself is the only
// condition signal. These branch keywords mirror the matching
// Bash cyclomatic decisions (`if`/`elif`/`while`; not `for`/
// `&&`/`||`), lifting ABC off 0 for `if cmd; then … elif … fi`.
// - The arithmetic ternary, Bash's only ternary form, matching
// the C-family `ConditionalExpression` and the Bash
// cyclomatic / cognitive arms that count it (#1268).
// `TernaryExpression2` is listed defensively per
// grammar-dispatch §1, as it is in those two siblings.
Bash::EQEQ
| Bash::BANGEQ
| Bash::LTEQ
| Bash::GTEQ
| Bash::EQTILDE
| Bash::TestOperator
| Bash::IfStatement
| Bash::ElifClause
| Bash::WhileStatement
| Bash::TernaryExpression
| Bash::TernaryExpression2 => {
stats.conditions += 1.;
}
// `<` and `>` are comparisons only inside a `binary_expression`.
// The same two tokens spell an I/O redirection (`cmd > out`,
// `read x < in`), which the grammar parents under
// `file_redirect` — so ungated they scored every redirect in a
// script as a condition. This is the Bash instance of the
// positive-parent gate #1280 applied to Ruby, and the polarity
// Rust / Go / C / C++ already use. At tree-sitter-bash 0.25.1
// only `BinaryExpression3` wraps a comparison; the four
// siblings are listed defensively per grammar-dispatch §1.
Bash::LT | Bash::GT
if ancestors.parent(node).is_some_and(|p| {
matches!(
p.kind_id().into(),
Bash::BinaryExpression
| Bash::BinaryExpression2
| Bash::BinaryExpression3
| Bash::BinaryExpression4
| Bash::BinaryExpression5
)
}) =>
{
stats.conditions += 1.;
}
// Case arms are conditions too, but counted per-arm like
// cyclomatic, excluding the bare-`*)` wildcard (the Bash analogue
// of `default:`) (#696).
Bash::CaseItem | Bash::CaseItem2
if !crate::metrics::cyclomatic::bash_case_item_is_bare_wildcard(node, code) =>
{
stats.conditions += 1.;
}
_ => {}
}
}
}