Rails/PostgreSQL problem: PG::ConnectionBad: fe_sendauth: no password supplied - ruby-on-rails

Question

I'm trying to run my tests for my app but I keep getting both this errors:
PG::ConnectionBad: fe_sendauth: no password supplied
PG::ConnectionBad: FATAL: sorry, too many clients already
I'be read all previous answers and it seems to be, for everybody else, either a missing password or a misconfiguration of the pg_hba.conf file.
This is how my database.yml looks like:
default: &default
adapter: postgresql
pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
timeout: 5000
encoding: utf8
reconnect: true
host: localhost
username: postgres
password: <password>
development:
<<: *default
database: <dev-db>
host: <dev-host>
username: <dev-user>
password: <dev-pass>
test:
<<: *default
database: <test-db>
I already checked the pg_hba.conf config file and its configured to md5 for all entries listed.
Any clues to what might be the problem?
I'm running PostgreSQL 10, Rails 5.2.3 on Ruby 2.5.5, on a Macbook with Mojave.
Thanks in advance.

Answer 1

Does your postgres user actually have a password set on it? Typically there is no password for the default postgres user, so this is something you would need to have gone out of your way to do; judging by the error message, it sounds like you are using the default posgres user and have not gone out of your way to set a password in the PostgreSQL CLI.
I suggest stripping it down to a very basic default, functional config like:
postgres: &postgres
adapter: postgresql
encoding: utf8
pool: 5
development:
<<: *postgres
database: project_name_development
test:
<<: *postgres
database: project_name_test
Then incrementally add back additional configuration options one at a time, confirming that each one works before adding the next. Env vars also may not be available to database.yml depending on your project configuration and installed gems.