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Using the global ARGs with default values should produce a valid build.
PropertyValue
SeverityError
CategoryCorrectness
DefaultEnabled

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Description

An ARG used in an image reference should be valid when no build arguments are used. An image build should not require --build-arg to produce a valid build. If a global ARG has no default value and is interpolated into a FROM instruction, the resulting image reference may be invalid when the argument is not supplied at build time.

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Examples

Bad: 
ARG TAG
FROM busybox:${TAG}
Good: 
ARG TAG=latest
FROM busybox:${TAG}
Good (empty ARG is OK if image is valid with it empty): 
ARG VARIANT
FROM busybox:stable${VARIANT}
Good (default value syntax): 
ARG TAG
FROM alpine:${TAG:-3.14}

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Reference