fix: Allow 'this' to be used in overridden commands (#18899)

packages/driver/cypress/integration/cypress/cy_spec.js

@@ -476,5 +476,20 @@ describe('driver/src/cypress/cy', () => {
         expect(cy.state('current').get('prev').get('args')[0].foo).to.equal('foo')
       })
     })
+
+    // https://github.com/cypress-io/cypress/issues/18892
+    it('passes this through to overwritten command', () => {
+      Cypress.Commands.add('bar', function () {
+        expect(this.test.title).to.exist
+      })
+
+      cy.bar()
+
+      Cypress.Commands.overwrite('bar', function (originalFn) {
+        return originalFn.call(this)
+      })
+
+      cy.bar()
+    })
   })
 })

packages/driver/src/cypress/commands.ts

@@ -58,7 +58,7 @@ export default {
       // store the backup again now
       commandBackups[name] = original
 
-      const originalFn = (...args) => {
+      function originalFn (...args) {
         const current = state('current')
         let storedArgs = args
 
@@ -68,7 +68,7 @@ export default {
 
         current.set('args', storedArgs)
 
-        return original.fn(...args)
+        return original.fn.apply(this, args)
       }
 
       const overridden = _.clone(original)