Docker special-cases build-contexts starting with `github.com`, and
treats them as remote URLs.
Because of this special treatment, local build contexts in a directory
named "github.com" are ignored by `docker build`.
This patch changes the way the build-context is detected and first
checks if a local path with the given name exists before considering
it to be a remote URL.
Before this change;
$ mkdir -p github.com/foo/bar && echo -e "FROM scratch\nLABEL iam=local" > github.com/foo/bar/Dockerfile
$ docker build -t dont-ignore-me github.com/foo/bar
Username for 'https://github.com':
After this change;
$ mkdir -p github.com/foo/bar && echo -e "FROM scratch\nLABEL iam=local" > github.com/foo/bar/Dockerfile
$ docker build -t dont-ignore-me github.com/foo/bar
Sending build context to Docker daemon 2.048 kB
Step 1/2 : FROM scratch
--->
Step 2/2 : LABEL iam local
---> Using cache
---> ae2c603fe970
Successfully built ae2c603fe970
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
bfd9613e5f