From b962775b8cb7c90985a5ab63e56744bb2ba79644 Mon Sep 17 00:00:00 2001
From: Tibor Blenessy <tibor.blenessy@sonarsource.com>
Date: Tue, 15 Oct 2019 23:55:02 +0200
Subject: [PATCH] Update: no-self-assign should detect member expression with
 this (#12279)

* Update: no-self-assign should detect member expression with this

* Remove redundant condition
---
 lib/rules/no-self-assign.js       |  3 +++
 tests/lib/rules/no-self-assign.js | 15 ++++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/rules/no-self-assign.js b/lib/rules/no-self-assign.js
index 9a06ebba6bc..705d0f409c4 100644
--- a/lib/rules/no-self-assign.js
+++ b/lib/rules/no-self-assign.js
@@ -61,6 +61,9 @@ function isSameMember(left, right) {
     if (lobj.type === "MemberExpression") {
         return isSameMember(lobj, robj);
     }
+    if (lobj.type === "ThisExpression") {
+        return true;
+    }
     return lobj.type === "Identifier" && lobj.name === robj.name;
 }
 
diff --git a/tests/lib/rules/no-self-assign.js b/tests/lib/rules/no-self-assign.js
index 4e168a89789..eaa0d02d12d 100644
--- a/tests/lib/rules/no-self-assign.js
+++ b/tests/lib/rules/no-self-assign.js
@@ -70,6 +70,14 @@ ruleTester.run("no-self-assign", rule, {
         {
             code: "a[\n    'b'\n] = a[\n    'b'\n]",
             options: [{ props: false }]
+        },
+        {
+            code: "this.x = this.y",
+            options: [{ props: true }]
+        },
+        {
+            code: "this.x = this.x",
+            options: [{ props: false }]
         }
     ],
     invalid: [
@@ -120,6 +128,11 @@ ruleTester.run("no-self-assign", rule, {
         { code: "a.b.c = a.b.c", options: [{ props: true }], errors: ["'a.b.c' is assigned to itself."] },
         { code: "a[b] = a[b]", options: [{ props: true }], errors: ["'a[b]' is assigned to itself."] },
         { code: "a['b'] = a['b']", options: [{ props: true }], errors: ["'a['b']' is assigned to itself."] },
-        { code: "a[\n    'b'\n] = a[\n    'b'\n]", options: [{ props: true }], errors: ["'a['b']' is assigned to itself."] }
+        { code: "a[\n    'b'\n] = a[\n    'b'\n]", options: [{ props: true }], errors: ["'a['b']' is assigned to itself."] },
+        {
+            code: "this.x = this.x",
+            options: [{ props: true }],
+            errors: ["'this.x' is assigned to itself."]
+        }
     ]
 });