feat(eslint-plugin): [prefer-optional-chain] support suggesting `!foo…

… || !foo.bar` as a valid match for the rule (#5266)
typescript-eslint · Aug 21, 2022 · aca935c · aca935c
1 parent c950051
commit aca935c
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diff --git a/packages/eslint-plugin/docs/rules/prefer-optional-chain.md b/packages/eslint-plugin/docs/rules/prefer-optional-chain.md
@@ -1,5 +1,5 @@
 ---
-description: 'Enforce using concise optional chain expressions instead of chained logical ands.'
+description: 'Enforce using concise optional chain expressions instead of chained logical ands, negated logical ors, or empty objects.'
 ---
 
 > 🛑 This file is source code, not the primary documentation location! 🛑
@@ -65,9 +65,15 @@ foo && foo.a && foo.a.b && foo.a.b.c;
 foo && foo['a'] && foo['a'].b && foo['a'].b.c;
 foo && foo.a && foo.a.b && foo.a.b.method && foo.a.b.method();
 
+// With empty objects
 (((foo || {}).a || {}).b || {}).c;
 (((foo || {})['a'] || {}).b || {}).c;
 
+// With negated `or`s
+!foo || !foo.bar;
+!foo || !foo[bar];
+!foo || !foo.bar || !foo.bar.baz || !foo.bar.baz();
+
 // this rule also supports converting chained strict nullish checks:
 foo &&
   foo.a != null &&
@@ -85,6 +91,10 @@ foo?.['a']?.b?.c;
 foo?.a?.b?.method?.();
 
 foo?.a?.b?.c?.d?.e;
+
+!foo?.bar;
+!foo?.[bar];
+!foo?.bar?.baz?.();
 ```
 
 **Note:** there are a few edge cases where this rule will false positive. Use your best judgement when evaluating reported errors.

diff --git a/packages/eslint-plugin/src/rules/explicit-function-return-type.ts b/packages/eslint-plugin/src/rules/explicit-function-return-type.ts
@@ -90,7 +90,7 @@ export default util.createRule<Options, MessageIds>({
         | TSESTree.FunctionExpression
         | TSESTree.FunctionDeclaration,
     ): boolean {
-      if (!options.allowedNames || !options.allowedNames.length) {
+      if (!options.allowedNames?.length) {
         return false;
       }
 

diff --git a/packages/eslint-plugin/src/rules/no-useless-constructor.ts b/packages/eslint-plugin/src/rules/no-useless-constructor.ts
@@ -34,13 +34,10 @@ function checkAccessibility(node: TSESTree.MethodDefinition): boolean {
  * Check if method is not useless due to typescript parameter properties and decorators
  */
 function checkParams(node: TSESTree.MethodDefinition): boolean {
-  return (
-    !node.value.params ||
-    !node.value.params.some(
-      param =>
-        param.type === AST_NODE_TYPES.TSParameterProperty ||
-        param.decorators?.length,
-    )
+  return !node.value.params.some(
+    param =>
+      param.type === AST_NODE_TYPES.TSParameterProperty ||
+      param.decorators?.length,
   );
 }