NoEmptyContinuation#

Output#

Empty continuation line found in: RUN apk add     gnupg     curl

Description#

Support for empty continuation (/) lines have been deprecated and will generate errors in future versions of the Dockerfile syntax.

Empty continuation lines are empty lines following a newline escape:

FROM alpine
RUN apk add \

    gnupg \

    curl

Support for such empty lines is deprecated, and a future BuildKit release will remove support for this syntax entirely, causing builds to break. To avoid future errors, remove the empty lines, or add comments, since lines with comments aren't considered empty.

Examples#

❌ Bad: empty continuation line between EXPOSE and 80.

FROM alpine
EXPOSE \

80

✅ Good: comments do not count as empty lines.

FROM alpine
EXPOSE \
# Port
80