refactor(rome_js_analyze): relax noConfusingArrow (#4593)

CHANGELOG.md

@@ -75,6 +75,21 @@ parameter decorators:
 
   The code action now removes any whitespace between the parameter name and its initialization.
 
+- Relax [noConfusingArrow](https://docs.rome.tools/lint/rules/noconfusingarrow/)
+
+  All arrow functions that enclose its parameter with parenthesis are allowed.
+  Thus, the following snippet no longer trigger the rule:
+
+  ```js
+  var x = (a) => 1 ? 2 : 3;
+  ```
+
+  The following snippet still triggers the rule:
+
+  ```js
+  var x = a => 1 ? 2 : 3;
+  ```
+
 - The rules [`useExhaustiveDependencies`](https://docs.rome.tools/lint/rules/useexhaustivedependencies/) and [`useHookAtTopLevel`](https://docs.rome.tools/lint/rules/usehookattoplevel/) accept a different shape of options
 
   Old configuration

crates/rome_js_analyze/src/analyzers/nursery/no_confusing_arrow.rs

@@ -17,19 +17,19 @@ declare_rule! {
     /// ```js,expect_diagnostic
     /// var x = a => 1 ? 2 : 3;
     /// ```
-    /// ```js,expect_diagnostic
-    /// var x = (a) => 1 ? 2 : 3;
-    /// ```
     ///
     /// ## Valid
     ///
     /// ```js
+    /// var x = (a) => 1 ? 2 : 3;
+    ///
     /// var x = a => (1 ? 2 : 3);
+    ///
     /// var x = (a) => (1 ? 2 : 3);
-    /// var x = (a) => {
-    ///     return 1 ? 2 : 3;
-    /// };
+    ///
     /// var x = a => { return 1 ? 2 : 3; };
+    ///
+    /// var x = (a) => { return 1 ? 2 : 3; };
     /// ```
     ///
     pub(crate) NoConfusingArrow {
@@ -47,7 +47,10 @@ impl Rule for NoConfusingArrow {
 
     fn run(ctx: &RuleContext<Self>) -> Self::Signals {
         let arrow_fn = ctx.query();
-
+        if arrow_fn.parameters().ok()?.as_js_parameters().is_some() {
+            // Don't report arrow functions that enclose its parameters with parenthesis.
+            return None;
+        }
         arrow_fn
             .body()
             .ok()?

crates/rome_js_analyze/tests/specs/nursery/noConfusingArrow/invalid.js

@@ -1,2 +1 @@
 var x = a => 1 ? 2 : 3;
-var x = (a) => 1 ? 2 : 3;

crates/rome_js_analyze/tests/specs/nursery/noConfusingArrow/invalid.js.snap

@@ -1,11 +1,11 @@
 ---
 source: crates/rome_js_analyze/tests/spec_tests.rs
+assertion_line: 100
 expression: invalid.js
 ---
 # Input
 ```js
 var x = a => 1 ? 2 : 3;
-var x = (a) => 1 ? 2 : 3;
 
 ```
 
@@ -17,21 +17,7 @@ invalid.js:1:11 lint/nursery/noConfusingArrow ━━━━━━━━━━━
   
   > 1 │ var x = a => 1 ? 2 : 3;
       │           ^^
-    2 │ var x = (a) => 1 ? 2 : 3;
-    3 │ 
-  
-
-```
-
-```
-invalid.js:2:13 lint/nursery/noConfusingArrow ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
-
-  ! Fat arrows can be confused with some comparison operators (<, >, <=, >=).
-  
-    1 │ var x = a => 1 ? 2 : 3;
-  > 2 │ var x = (a) => 1 ? 2 : 3;
-      │             ^^
-    3 │ 
+    2 │ 
   
 
 ```

crates/rome_js_analyze/tests/specs/nursery/noConfusingArrow/valid.js

@@ -1,8 +1,11 @@
 /* should not generate diagnostics */
 
 var x = a => (1 ? 2 : 3);
+
+var x = (a) => 1 ? 2 : 3;
+
 var x = (a) => (1 ? 2 : 3);
-var x = (a) => {
-    return 1 ? 2 : 3;
-};
+
+var x = (a) => { return 1 ? 2 : 3; };
+
 var x = a => { return 1 ? 2 : 3; };

crates/rome_js_analyze/tests/specs/nursery/noConfusingArrow/valid.js.snap

@@ -1,16 +1,20 @@
 ---
 source: crates/rome_js_analyze/tests/spec_tests.rs
+assertion_line: 100
 expression: valid.js
 ---
 # Input
 ```js
 /* should not generate diagnostics */
 
 var x = a => (1 ? 2 : 3);
+
+var x = (a) => 1 ? 2 : 3;
+
 var x = (a) => (1 ? 2 : 3);
-var x = (a) => {
-    return 1 ? 2 : 3;
-};
+
+var x = (a) => { return 1 ? 2 : 3; };
+
 var x = a => { return 1 ? 2 : 3; };
 
 ```