Bitbucket pipelines not using cache for bundle install - ruby

Question

I have tried every variation of naming my cache and nothing seems to work
My cache is being downloaded properly as I can see in the build setup.
Cache "bundler": Downloading
Cache "bundler": Downloaded 25.2 MiB in 1 seconds
Cache "bundler": Extracting
Cache "bundler": Extracted in 0 seconds
however when I go to bundle install I always get
Fetching gem metadata from https://rubygems.org/.......
Installing rake 12.3.3
Installing concurrent-ruby 1.1.5
Installing i18n 0.9.5
Installing minitest 5.11.3
Installing thread_safe 0.3.6
Installing tzinfo 1.2.5
Installing activesupport 5.2.3
Installing builder 3.2.3
..........
Here is my bitbucket-pipelines.yml
pipelines:
default:
- step:
name: Run Tests
image: ruby:2.6.4
caches:
- bundler
script:
- apt-get update && apt-get install -y build-essential libpq-dev nodejs python-dev
- bundle install --path ./vendor
- cp config/database.yml.example config/database.yml
- RAILS_ENV=test bundle exec rake db:setup
- RAILS_ENV=test bundle exec rake db:schema:load
- RAILS_ENV=test bundle exec rspec
services:
- postgres
- redis
definitions:
caches:
bundler: ./vendor
services:
redis:
image: redis
postgres:
image: postgres
environment:
POSTGRES_DB: 'xxxxx'
POSTGRES_USER: 'xxxxx'
POSTGRES_PASSWORD: 'xxxxx'

Answer 1

I hope you are solved you problem, the BitBucket Caches docs are out of date. So a solved my problem with this commands:
- gem install bundler -v 2.1.4
- bundle config set path 'vendor/bundle'
- bundle install
- bundle binstubs --all
My be, is needed remove tzinfo-data for linux deploy.
You can understand more reading the bundle binstubs docs.