Get error "ClassyTestCase is not defined"

My package

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meteor-base@1.3.0             # Packages every Meteor app needs to have
mobile-experience@1.0.5       # Packages for a great mobile UX
mongo@1.4.2                   # The database Meteor supports right now
blaze-html-templates@1.0.4 # Compile .html files into Meteor Blaze views
reactive-var@1.0.11            # Reactive variable for tracker
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#--- Core ---
check
accounts-base
accounts-password
ddp-rate-limiter
session
less
http
ejson
dynamic-import

#--- Community ---
# Vue
akryum:vue-component
akryum:vue-sass
#nathantreid:vue-css-modules

vuejs:blaze-integration
u2622:persistent-session

# Roles
alanning:roles
ongoworks:security

# Collection
aldeed:collection2-core
aldeed:schema-index
matb33:collection-hooks
dburles:collection-helpers
meteorhacks:aggregate
tmeasday:publish-counts

# Method
mdg:validated-method
didericis:callpromise-mixin

# Collection Extensions
lai:collection-extensions

# Path & File
ostrio:meteor-root
pfafman:filesaver

nathantreid:static-assets

I don’t use peerlibrary_computed-field package, why get it an error?

I would think that one of your other packages is using it.

Yes I have problem with lai:collection-extensions