use crate::{
LintLevel,
ast::declaration,
context::LintContext,
rule::{DetectFix, Rule},
violation::Detection,
};
const MAX_LINES: usize = 40;
fn check(context: &LintContext) -> Vec<Detection> {
context
.custom_commands()
.iter()
.filter_map(|def| function_violation(context, def))
.collect()
}
fn function_violation(
context: &LintContext<'_>,
def: &declaration::CustomCommandDef,
) -> Option<Detection> {
let block = context.working_set.get_block(def.body);
let block_span = block.span?;
let line_count = context.span_text(block_span).lines().count();
(line_count > MAX_LINES).then(|| {
let message = format!(
"Function `{}` has {line_count} lines, which exceeds the maximum of {MAX_LINES} lines",
def.name
);
Detection::from_file_span(message, def.declaration_span(context))
.with_primary_label(format!("{line_count} lines"))
.with_extra_label("function body", block_span)
})
}
struct TooManyLines;
impl DetectFix for TooManyLines {
type FixInput<'a> = ();
fn id(&self) -> &'static str {
"max_function_body_length"
}
fn short_description(&self) -> &'static str {
"Function bodies should be short to maintain readability"
}
fn long_description(&self) -> Option<&'static str> {
Some(
"Consider refactoring into smaller, more focused functions with clear responsibilities",
)
}
fn source_link(&self) -> Option<&'static str> {
Some("https://www.nushell.sh/book/custom_commands.html")
}
fn level(&self) -> LintLevel {
LintLevel::Hint
}
fn detect<'a>(&self, context: &'a LintContext) -> Vec<(Detection, Self::FixInput<'a>)> {
Self::no_fix(check(context))
}
}
pub static RULE: &dyn Rule = &TooManyLines;
#[cfg(test)]
mod detect_bad;
#[cfg(test)]
mod ignore_good;