feat(linter) eslint plugin unicorn prefer string trim start end (#1148)

crates/oxc_linter/src/rules.rs

@@ -150,6 +150,7 @@ mod unicorn {
     pub mod prefer_array_flat_map;
     pub mod prefer_logical_operator_over_ternary;
     pub mod prefer_query_selector;
+    pub mod prefer_string_trim_start_end;
     pub mod require_number_to_fixed_digits_argument;
     pub mod switch_case_braces;
     pub mod text_encoding_identifier_case;
@@ -275,6 +276,7 @@ oxc_macros::declare_all_lint_rules! {
     unicorn::switch_case_braces,
     unicorn::text_encoding_identifier_case,
     unicorn::throw_new_error,
+    unicorn::prefer_string_trim_start_end,
     unicorn::prefer_query_selector,
     react::jsx_key,
     react::jsx_no_comment_text_nodes,

crates/oxc_linter/src/rules/unicorn/prefer_string_trim_start_end.rs

@@ -0,0 +1,115 @@
+use oxc_ast::{ast::MemberExpression, AstKind};
+use oxc_diagnostics::{
+    miette::{self, Diagnostic},
+    thiserror::{self, Error},
+};
+use oxc_macros::declare_oxc_lint;
+use oxc_span::{Atom, Span};
+
+use crate::{context::LintContext, rule::Rule, AstNode};
+
+#[derive(Debug, Error, Diagnostic)]
+#[error("eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `{1}` over `{2}`")]
+#[diagnostic(severity(warning), help("Replace with `{1}`"))]
+struct PreferStringTrimStartEndDiagnostic(#[label] pub Span, Atom, &'static str);
+
+#[derive(Debug, Default, Clone)]
+pub struct PreferStringTrimStartEnd;
+
+declare_oxc_lint!(
+    /// ### What it does
+    ///
+    /// [`String#trimLeft()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/trimLeft) and [`String#trimRight()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/trimRight) are aliases of [`String#trimStart()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/trimStart) and [`String#trimEnd()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/trimEnd). This is to ensure consistency and use [direction](https://developer.mozilla.org/en-US/docs/Learn/CSS/Building_blocks/Handling_different_text_directions)-independent wording.
+    ///
+    /// ### Why is this bad?
+    ///
+    /// The `trimLeft` and `trimRight` names are confusing and inconsistent with the rest of the language.
+    ///
+    /// ### Example
+    /// ```javascript
+    /// // Bad
+    /// str.trimLeft();
+    /// str.trimRight();
+    ///
+    /// // Good
+    /// str.trimStart();
+    /// str.trimEnd();
+    /// ```
+    PreferStringTrimStartEnd,
+    style
+);
+
+impl Rule for PreferStringTrimStartEnd {
+    fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {
+        let AstKind::CallExpression(call_expr) = node.kind() else {
+            return;
+        };
+
+        if call_expr.optional {
+            return;
+        }
+
+        let Some(member_expr) = call_expr.callee.get_member_expr() else { return };
+
+        let (span, name) = match member_expr {
+            MemberExpression::StaticMemberExpression(v) => {
+                if !matches!(v.property.name.as_str(), "trimLeft" | "trimRight") {
+                    return;
+                }
+                (v.property.span, &v.property.name)
+            }
+            _ => return,
+        };
+
+        if !call_expr.arguments.is_empty() {
+            return;
+        }
+
+        ctx.diagnostic(PreferStringTrimStartEndDiagnostic(
+            span,
+            name.clone(),
+            get_replacement(name.as_str()),
+        ));
+    }
+}
+
+fn get_replacement(name: &str) -> &'static str {
+    match name {
+        "trimLeft" => "trimStart",
+        "trimRight" => "trimEnd",
+        _ => unreachable!(),
+    }
+}
+
+#[test]
+fn test() {
+    use crate::tester::Tester;
+
+    let pass = vec![
+        r#"foo.trimStart()"#,
+        r#"foo.trimStart?.()"#,
+        r#"foo.trimEnd()"#,
+        r#"new foo.trimLeft();"#,
+        r#"trimLeft();"#,
+        r#"foo['trimLeft']();"#,
+        r#"foo[trimLeft]();"#,
+        r#"foo.bar();"#,
+        r#"foo.trimLeft(extra);"#,
+        r#"foo.trimLeft(...argumentsArray)"#,
+        r#"foo.bar(trimLeft)"#,
+        r#"foo.bar(foo.trimLeft)"#,
+        r#"trimLeft.foo()"#,
+        r#"foo.trimLeft.bar()"#,
+    ];
+
+    let fail = vec![
+        r#"foo.trimLeft()"#,
+        r#"foo.trimRight()"#,
+        r#"trimLeft.trimRight()"#,
+        r#"foo.trimLeft.trimRight()"#,
+        r#""foo".trimLeft()"#,
+        r#"foo?.trimLeft()"#,
+    ];
+
+    Tester::new_without_config(PreferStringTrimStartEnd::NAME, pass, fail).test_and_snapshot();
+}

crates/oxc_linter/src/snapshots/prefer_string_trim_start_end.snap

@@ -0,0 +1,47 @@
+---
+source: crates/oxc_linter/src/tester.rs
+expression: prefer_string_trim_start_end
+---
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimLeft` over `trimStart`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ foo.trimLeft()
+   ·     ────────
+   ╰────
+  help: Replace with `trimLeft`
+
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimRight` over `trimEnd`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ foo.trimRight()
+   ·     ─────────
+   ╰────
+  help: Replace with `trimRight`
+
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimRight` over `trimEnd`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ trimLeft.trimRight()
+   ·          ─────────
+   ╰────
+  help: Replace with `trimRight`
+
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimRight` over `trimEnd`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ foo.trimLeft.trimRight()
+   ·              ─────────
+   ╰────
+  help: Replace with `trimRight`
+
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimLeft` over `trimStart`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ "foo".trimLeft()
+   ·       ────────
+   ╰────
+  help: Replace with `trimLeft`
+
+  ⚠ eslint-plugin-unicorn(prefer-string-trim-start-end): Prefer `trimLeft` over `trimStart`
+   ╭─[prefer_string_trim_start_end.tsx:1:1]
+ 1 │ foo?.trimLeft()
+   ·      ────────
+   ╰────
+  help: Replace with `trimLeft`
+
+