```
FROM alpine
RUN echo "Hey $name"
```
When building the above Dockerfile, the RUN command used to show: `echo Hey `
With this patch it now shows `echo "Hey $name"`.
However, because it is very useful for debugging to see the values variables can take,
they are expanded if set.
```
FROM alpine
ENV name=Jude
RUN echo "Hey $name"
```
Building the above Dockerfile makes the RUN command show: `echo "Hey Jude"`.
Signed-off-by: Tibor Vass <tibor@docker.com>
Detect Special parameters as defined in
http://pubs.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_05_02
Treat these as parameters that are not set, instead of
producing an error that a modifier is missing.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
rewritten from github.com/moby/moby 9654e9b6f80e1b931763c04400a19596e256c99a
`${}`, `${:}` and so on are invalid because there's
no parameter within the brackets; fix detection for
this situation and add/update tests.
There were some existing test-cases that were testing
for the wrong behavior, which are now updated.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
rewritten from github.com/moby/moby 334bf3ea76004d0abe02dd1698989f9eaf87a86a
The builder did not detect syntax errors in substitusions in the
Dockerfile, causing those values to be processed incorrectly instead of
producing an error.
Example 1: missing `}`
docker build --no-cache -<<'EOF'
FROM busybox
ARG var=${aaa:-bbb
RUN echo $var
EOF
Before:
Step 3/3 : RUN echo $var
---> Running in f06571e77146
bbb
After:
Step 2/3 : ARG var=${aaa:-bbb
failed to process "${aaa:-bbb": syntax error: missing '}'
Example 2: missing closing `}`, no default value
docker build --no-cache -<<'EOF'
FROM busybox
ARG var=${aaa
RUN echo $var
EOF
Before:
Step 2/3 : ARG var=${aaa
failed to process "${aaa": missing ':' in substitution
After:
Step 2/3 : ARG var=${aaa
failed to process "${aaa": syntax error: missing '}'
Example 3: double opening bracket (`{`)
docker build --no-cache -<<'EOF'
FROM busybox
ARG var=${{aaa:-bbb}
RUN echo $var
EOF
Before:
Step 2/3 : ARG var=${{aaa:-bbb}
failed to process "${{aaa:-bbb}": missing ':' in substitution
After:
Step 2/3 : ARG var=${{aaa:-bbb}
failed to process "${{aaa:-bbb}": syntax error: bad substitution
Example 4: double opening bracket (`{`), no default value
docker build --no-cache -<<'EOF'
FROM busybox
ARG var=${{aaa}
RUN echo $var
EOF
Before:
Step 2/3 : ARG var=${{aaa}
failed to process "${{aaa}": missing ':' in substitution
After:
Step 2/3 : ARG var=${{aaa}
failed to process "${{aaa}": syntax error: bad substitution
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
rewritten from github.com/moby/moby 955a6ad95f7891a45692d975793abf1eeb07cdd5
Moves builder/shell_parser and into its own subpackage at builder/shell since it
has no dependencies other than the standard library. This will make it
much easier to vendor for downstream libraries, without pulling all the
dependencies of builder/.
Fixes#36154
Signed-off-by: Matt Rickard <mrick@google.com>
rewritten from github.com/moby/moby a634526d14639c6b98c509a069ef29e2b69c0ef0
Oliver Bristow
Tibor Vass
Yuichiro Kaneko
Tonis Tiigi
Sebastiaan van Stijn
Daniel Nephin
Matt Rickard