Prevent paste in within ancestor folder

apps/remix-ide/src/app/files/fileManager.ts

@@ -272,7 +272,13 @@ class FileManager extends Plugin {
       await this._handleIsDir(src, `Cannot copy from ${src}. Path is not a directory.`)
       await this._handleExists(dest, `Cannot paste content into ${dest}. Path does not exist.`)
       await this._handleIsDir(dest, `Cannot paste content into ${dest}. Path is not directory.`)
+
+      const provider = this.fileProviderOf(src)
+      if (provider.isSubDirectory(src, dest)) {
+        this.call('notification', 'toast', 'File(s) to paste is an ancestor of the destination folder')
+      } else {
         await this.inDepthCopy(src, dest)
+      }
     } catch (e) {
       throw new Error(e)
     }

apps/remix-ide/src/app/files/remixDProvider.js

@@ -1,5 +1,6 @@
 'use strict'
 const FileProvider = require('./fileProvider')
+const pathModule = require('path')
 
 module.exports = class RemixDProvider extends FileProvider {
   constructor (appManager) {
@@ -207,4 +208,12 @@ module.exports = class RemixDProvider extends FileProvider {
     if (!this._isReady) throw new Error('provider not ready')
     return await this._appManager.call('remixd', 'isFile', { path: unprefixedpath })
   }
+
+  isSubDirectory (parent, child) {
+    if (!parent) return false
+    if (parent === child) return true
+    const relative = pathModule.relative(parent, child)
+
+    return !!relative && relative.split(pathModule.sep)[0] !== '..'
+  }
 }