From b757bd8d6910dc1b75f014eaec1f2d36fa38cf4d Mon Sep 17 00:00:00 2001
From: Anix <anik220798@gmail.com>
Date: Fri, 24 Apr 2020 08:45:16 +0000
Subject: [PATCH] Fix: clone config data before validation (fixes #12592)

---
 lib/cli-engine/config-array-factory.js |  4 +++-
 tests/lib/rules/camelcase.js           | 23 +++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/cli-engine/config-array-factory.js b/lib/cli-engine/config-array-factory.js
index 997a7e15318..74a8319217a 100644
--- a/lib/cli-engine/config-array-factory.js
+++ b/lib/cli-engine/config-array-factory.js
@@ -43,6 +43,7 @@ const fs = require("fs");
 const path = require("path");
 const importFresh = require("import-fresh");
 const stripComments = require("strip-json-comments");
+const lodash = require("lodash");
 const { validateConfigSchema } = require("../shared/config-validator");
 const naming = require("../shared/naming");
 const ModuleResolver = require("../shared/relative-module-resolver");
@@ -593,8 +594,9 @@ class ConfigArrayFactory {
             ? path.resolve(cwd, providedFilePath)
             : "";
         const name = providedName || (filePath && path.relative(cwd, filePath));
+        const clonedConfig = lodash.cloneDeep(configData);
 
-        validateConfigSchema(configData, name || filePath);
+        validateConfigSchema(clonedConfig, name || filePath);
 
         return this._normalizeObjectConfigData(configData, filePath, name);
     }
diff --git a/tests/lib/rules/camelcase.js b/tests/lib/rules/camelcase.js
index 21f280adb35..80dbe183c9d 100644
--- a/tests/lib/rules/camelcase.js
+++ b/tests/lib/rules/camelcase.js
@@ -225,6 +225,10 @@ ruleTester.run("camelcase", rule, {
             code: "foo = { [computedBar]: 0 };",
             options: [{ ignoreDestructuring: true }],
             parserOptions: { ecmaVersion: 6 }
+        },
+        {
+            code: "var obj = { mem_var: 1 };",
+            options: [{ properties: "never" }]
         }
     ],
     invalid: [
@@ -736,6 +740,25 @@ ruleTester.run("camelcase", rule, {
                     type: "Identifier"
                 }
             ]
+        },
+        {
+            code: "const {mem_var = 1} = obh",
+            options: [{ ignoreDestructuring: false }],
+            parserOptions: { ecmaVersion: 6 },
+            errors: [{
+                messageId: "notCamelCase",
+                data: { name: "mem_var" },
+                type: "Identifier"
+            }]
+        },
+        {
+            code: "var obj = { mem_var: 1 };",
+            options: [{}],
+            errors: [{
+                messageId: "notCamelCase",
+                data: { name: "mem_var" },
+                type: "Identifier"
+            }]
         }
     ]
 });