combination of warnings, errors and hints can get confusing

[thaJeztah]

Related to #5240, where I made a mistake in my HEREDOC syntax. Just jotting it down here; not sure what the best output would look like, but I think the combination of errors, warnings, hints being intertwined can be confusing.

Looking back at that ticket, I also realize now that the expanded ("per line") output is not related to the linting, but to the error. I recall I initially used the wrong delimited (used EOF for both the Dockerfile and the RUN heredoc); the combination of a warning and error quickly gets confusing as they're all interleaved;

In this case

• error (RUN failed)
• X warnings found
• summary of warning(s)
• details about error
• error (again)
• hint (view build details)

docker build --progress=plain --no-cache -<<'EOF'
# syntax=docker/dockerfile:1

FROM alpine
RUN -<<'EOF'
env foo=bar
EOF
EOF

# .....
#9 [2/2] RUN -<<'EOF'
#9 0.116 /bin/sh: illegal option -<
#9 ERROR: process "/bin/sh -c -<<'EOF'" did not complete successfully: exit code: 2
------
 > [2/2] RUN -<<'EOF':
0.116 /bin/sh: illegal option -<
------

 1 warning found (use docker --debug to expand):
 - ConsistentInstructionCasing: Command 'env' should match the case of the command majority (uppercase) (line 5)
Dockerfile:4
--------------------
   2 |
   3 |     FROM alpine
   4 | >>> RUN -<<'EOF'
   5 |     env foo=bar
   6 |
--------------------
ERROR: failed to solve: process "/bin/sh -c -<<'EOF'" did not complete successfully: exit code: 2

View build details: docker-desktop://dashboard/build/desktop-linux/desktop-linux/aiqna4u2fi004x8x3qriz463i
bash: EOF: command not found

After "fixing" the EOF -> EOT mistake;

• warnings found
• summary of warnings
• error-details
• error
• hint

docker build --progress=plain --no-cache -<<'EOF'
# syntax=docker/dockerfile:1

FROM alpine
RUN -<<'EOT'
env foo=bar
EOT
EOF

# .....
#3 CACHED

 1 warning found (use docker --debug to expand):
 - ConsistentInstructionCasing: Command 'env' should match the case of the command majority (uppercase) (line 5)
Dockerfile:6
--------------------
   4 |     RUN -<<'EOT'
   5 |     env foo=bar
   6 | >>> EOT
   7 |
--------------------
ERROR: failed to solve: dockerfile parse error on line 6: unknown instruction: EOT (did you mean ENV?)

View build details: docker-desktop://dashboard/build/desktop-linux/desktop-linux/lcjyf5gzycy3bedca61xnnysz

Without heredoc (on Docker Desktop with scout plugin installed);

• hint
• warnings found
• summary of warnings
• scout hint

docker build --progress=plain --no-cache -<<'EOF'
# syntax=docker/dockerfile:1

FROM alpine
RUN echo foo
env foo=bar
EOF

#8 DONE 0.0s

View build details: docker-desktop://dashboard/build/desktop-linux/desktop-linux/pdudz3dywoxrroyc77rekkztx

 1 warning found (use docker --debug to expand):
 - ConsistentInstructionCasing: Command 'env' should match the case of the command majority (uppercase) (line 5)

What's next:
    View a summary of image vulnerabilities and recommendations → docker scout quickview

[thaJeztah]

cc @daghack (sorry the ticket is a bit random; it's mostly output from some things I was testing - hope it's still useful though 🙈)