From 0d2c977c11de85de07591f524a1d84ec15fac26b Mon Sep 17 00:00:00 2001
From: Wang Wenzhe <mysteryven@gmail.com>
Date: Tue, 28 May 2024 22:50:54 +0800
Subject: [PATCH] feat(linter): add `oxc/no-const-enum` rule (#3435)

---
 crates/oxc_ast/src/ast/ts.rs                  |  7 ++
 crates/oxc_linter/src/rules.rs                |  2 +
 .../oxc_linter/src/rules/oxc/no_const_enum.rs | 84 +++++++++++++++++++
 .../src/snapshots/no_const_enum.snap          | 10 +++
 4 files changed, 103 insertions(+)
 create mode 100644 crates/oxc_linter/src/rules/oxc/no_const_enum.rs
 create mode 100644 crates/oxc_linter/src/snapshots/no_const_enum.snap

diff --git a/crates/oxc_ast/src/ast/ts.rs b/crates/oxc_ast/src/ast/ts.rs
index e0b7b5cf4..7cbbdb32c 100644
--- a/crates/oxc_ast/src/ast/ts.rs
+++ b/crates/oxc_ast/src/ast/ts.rs
@@ -1288,6 +1288,13 @@ impl<'a> Modifiers<'a> {
             .map_or(false, |modifiers| modifiers.iter().any(|modifier| modifier.kind == target))
     }
 
+    pub fn find<F>(&self, f: F) -> Option<&Modifier>
+    where
+        F: Fn(&Modifier) -> bool,
+    {
+        self.0.as_ref().and_then(|modifiers| modifiers.iter().find(|modifier| f(modifier)))
+    }
+
     pub fn is_contains_declare(&self) -> bool {
         self.contains(ModifierKind::Declare)
     }
diff --git a/crates/oxc_linter/src/rules.rs b/crates/oxc_linter/src/rules.rs
index d1400ca8a..cc0a1e80e 100644
--- a/crates/oxc_linter/src/rules.rs
+++ b/crates/oxc_linter/src/rules.rs
@@ -350,6 +350,7 @@ mod oxc {
     pub mod no_accumulating_spread;
     pub mod no_async_await;
     pub mod no_barrel_file;
+    pub mod no_const_enum;
     pub mod number_arg_out_of_range;
     pub mod only_used_in_recursion;
     pub mod uninvoked_array_callback;
@@ -718,6 +719,7 @@ oxc_macros::declare_all_lint_rules! {
     oxc::missing_throw,
     oxc::no_accumulating_spread,
     oxc::no_barrel_file,
+    oxc::no_const_enum,
     oxc::number_arg_out_of_range,
     oxc::only_used_in_recursion,
     oxc::no_async_await,
diff --git a/crates/oxc_linter/src/rules/oxc/no_const_enum.rs b/crates/oxc_linter/src/rules/oxc/no_const_enum.rs
new file mode 100644
index 000000000..f3156b0fd
--- /dev/null
+++ b/crates/oxc_linter/src/rules/oxc/no_const_enum.rs
@@ -0,0 +1,84 @@
+use oxc_ast::{ast::ModifierKind, AstKind};
+use oxc_diagnostics::OxcDiagnostic;
+use oxc_macros::declare_oxc_lint;
+use oxc_span::Span;
+
+use crate::{context::LintContext, fixer::Fix, rule::Rule, AstNode};
+
+fn no_const_enum_diagnostic(span0: Span) -> OxcDiagnostic {
+    OxcDiagnostic::warn("oxc(no-const-enum): Unexpected const enum")
+        .with_help("Const enums are not supported by bundlers and are incompatible with the isolatedModules mode. Their use can lead to import nonexistent values (because const enums are erased).")
+        .with_labels([span0.into()])
+}
+
+#[derive(Debug, Default, Clone)]
+pub struct NoConstEnum;
+
+// Ported from <https://biomejs.dev/linter/rules/no-const-enum/>
+declare_oxc_lint!(
+    /// ### What it does
+    ///
+    /// Disallow TypeScript `const enum`
+    ///
+    /// ### Why is this bad?
+    ///
+    /// Const enums are enums that should be inlined at use sites.
+    /// Const enums are not supported by bundlers and are incompatible with the isolatedModules mode.
+    /// Their use can lead to import nonexistent values (because const enums are erased).
+    ///
+    /// ### Example
+    /// ```javascript
+    /// const enum Color {
+    ///    Red,
+    ///    Green,
+    ///    Blue
+    /// }
+    /// ```
+    NoConstEnum,
+    restriction,
+);
+
+impl Rule for NoConstEnum {
+    fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {
+        if let AstKind::TSEnumDeclaration(enum_decl) = node.kind() {
+            let Some(const_enum) =
+                enum_decl.modifiers.find(|modifier| matches!(modifier.kind, ModifierKind::Const))
+            else {
+                return;
+            };
+
+            ctx.diagnostic_with_fix(no_const_enum_diagnostic(const_enum.span), || {
+                // const enum Color { Red, Green, Blue }
+                // ^
+                let start = const_enum.span.start;
+
+                // const enum Color { Red, Green, Blue }
+                // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+                let text = Span::new(start, enum_decl.span.end).source_text(ctx.source_text());
+
+                // const  enum Color { Red, Green, Blue }
+                //  ^^^^^^
+                let offset = u32::try_from(text.find("enum").unwrap_or(1)).unwrap_or(1); // 1 is the default offset
+
+                let end = start + offset;
+                Fix::delete(Span::new(start, end))
+            });
+        }
+    }
+}
+
+#[test]
+fn test() {
+    use crate::tester::Tester;
+
+    let pass = vec!["enum Color { Red, Green, Blue }"];
+
+    let fail = vec!["const enum Color { Red, Green, Blue }"];
+
+    let fix = vec![
+        ("const enum Color { Red, Green, Blue }", "enum Color { Red, Green, Blue }", None),
+        ("const   enum Color { Red, Green, Blue }", "enum Color { Red, Green, Blue }", None),
+    ];
+
+    Tester::new(NoConstEnum::NAME, pass, fail).expect_fix(fix).test_and_snapshot();
+}
diff --git a/crates/oxc_linter/src/snapshots/no_const_enum.snap b/crates/oxc_linter/src/snapshots/no_const_enum.snap
new file mode 100644
index 000000000..abf712fee
--- /dev/null
+++ b/crates/oxc_linter/src/snapshots/no_const_enum.snap
@@ -0,0 +1,10 @@
+---
+source: crates/oxc_linter/src/tester.rs
+expression: no_const_enum
+---
+  ⚠ oxc(no-const-enum): Unexpected const enum
+   ╭─[no_const_enum.tsx:1:1]
+ 1 │ const enum Color { Red, Green, Blue }
+   · ─────
+   ╰────
+  help: Const enums are not supported by bundlers and are incompatible with the isolatedModules mode. Their use can lead to import nonexistent values (because const enums are erased).