feat: handle logical assignment in no-self-assign (#14152)

* Fix: handle logical assignment in no-self-assign * ignore `&=` and `|=`
eslint · Dec 30, 2021 · 6802a54 · 6802a54
1 parent 3b38018
commit 6802a54
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diff --git a/docs/rules/no-self-assign.md b/docs/rules/no-self-assign.md
@@ -24,6 +24,10 @@ foo = foo;
 [a, ...b] = [x, ...b];
 
 ({a, b} = {a, x});
+
+foo &&= foo;
+foo ||= foo;
+foo ??= foo;
 ```
 
 Examples of **correct** code for this rule:
@@ -50,6 +54,10 @@ obj[a] = obj["a"];
 obj.a().b = obj.a().b;
 a().b = a().b;
 
+// `&=` and `|=` have an effect on non-integers.
+foo &= foo;
+foo |= foo;
+
 // Known limitation: this does not support computed properties except single literal or single identifier.
 obj[a + b] = obj[a + b];
 obj["a" + "b"] = obj["a" + "b"];

diff --git a/lib/rules/no-self-assign.js b/lib/rules/no-self-assign.js
@@ -174,7 +174,7 @@ module.exports = {
 
         return {
             AssignmentExpression(node) {
-                if (node.operator === "=") {
+                if (["=", "&&=", "||=", "??="].includes(node.operator)) {
                     eachSelfAssignment(node.left, node.right, props, report);
                 }
             }

diff --git a/tests/lib/rules/no-self-assign.js b/tests/lib/rules/no-self-assign.js
@@ -25,6 +25,8 @@ ruleTester.run("no-self-assign", rule, {
         "a += a",
         "a = +a",
         "a = [a]",
+        "a &= a",
+        "a |= a",
         { code: "let a = a", parserOptions: { ecmaVersion: 6 } },
         { code: "const a = a", parserOptions: { ecmaVersion: 6 } },
         { code: "[a] = a", parserOptions: { ecmaVersion: 6 } },
@@ -167,6 +169,23 @@ ruleTester.run("no-self-assign", rule, {
             code: "class C { #field; foo() { [this.#field] = [this.#field]; } }",
             parserOptions: { ecmaVersion: 2022 },
             errors: [{ messageId: "selfAssignment", data: { name: "this.#field" } }]
+        },
+
+        // logical assignment
+        {
+            code: "a &&= a",
+            parserOptions: { ecmaVersion: 2021 },
+            errors: [{ messageId: "selfAssignment", data: { name: "a" } }]
+        },
+        {
+            code: "a ||= a",
+            parserOptions: { ecmaVersion: 2021 },
+            errors: [{ messageId: "selfAssignment", data: { name: "a" } }]
+        },
+        {
+            code: "a ??= a",
+            parserOptions: { ecmaVersion: 2021 },
+            errors: [{ messageId: "selfAssignment", data: { name: "a" } }]
         }
     ]
 });