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Code Inspections in Dockerfile

This topic lists all PhpStorm code inspections available in Dockerfile.

You can toggle specific inspections or change their severity level on the Editor | Inspections page of the IDE settings Ctrl+Alt+S.

InspectionDescriptionDefault Severity
Invalid destination for ''ADD''/''COPY'' commands

Reports invalid destination directories in ADD and COPY commands.

According to the Dockerfile specification, if multiple sources are specified, then the destination must be a directory, and it must end with a slash '/'. Otherwise, Docker build will fail.


# all the commands below will fail ADD textA.txt textB.txt relativeDir ADD ["binaryA.jar", "binary2.jar", "destination"] COPY text3.txt text4.txt /absolute/path

After the quick-fix is applied:
ADD textA.txt textB.txt relativeDir/ ADD ["binaryA.jar", "binary2.jar", "destination/"] COPY text3.txt text4.txt /absolute/path/

Warning Warning
Invalid spaces in ''key=value'' pair

Reports incorrect spacing for key-value pairs in ARG, ENV, and LABEL commands.

While it is not explicitly specified in the Dockerfile specification, some combinations of spacing for key-value pairs are not allowed. Docker build will fail after reaching the problem instruction.


  • The ARG command does not allow any spaces around '='

  • ENV and LABEL do not allow spaces after '='

# all the commands below will fail ARG answer = 42 ARG version= "1.0.0" LABEL ""= ENV JAVA_HOME= "/docker-java-home"

After the quick-fix is applied:
ARG answer=2 ARG version="1.0.0" LABEL "" ENV JAVA_HOME="/docker-java-home"

Error Error
Wrong number of arguments

Reports invalid number of arguments for the Dockerfile commands.

Docker build will fail after reaching the instruction with an invalid number of arguments.

Error Error
Last modified: 16 July 2021