Multiline instructions with embedded comments confuses Instruction's getArguments()

[rcjsuen]

Given the Dockerfile below, the extra continuation newlines and comments should be ignored.

FROM alpine
RUN echo \
# comment

# comment
"Hello"

$ docker build .
Sending build context to Docker daemon  38.15MB
[WARNING]: Empty continuation line found in:
    RUN echo "Hello"
[WARNING]: Empty continuation lines will become errors in a future release.
Step 1/2 : FROM alpine
latest: Pulling from library/alpine
c9b1b535fdd9: Pull complete 
Digest: sha256:ab00606a42621fb68f2ed6ad3c88be54397f981a7b70a79db3d1172b11c4367d
Status: Downloaded newer image for alpine:latest
 ---> e7d92cdc71fe
Step 2/2 : RUN echo "Hello"
 ---> Running in 5a49db1abc9d
Hello
Removing intermediate container 5a49db1abc9d
 ---> 60a307c69178
Successfully built 60a307c69178

However, it appears to be confusing the parser and it thinks there are four arguments when there are only two.

import { DockerfileParser } from 'dockerfile-ast';
let content =
    "FROM alpine\n" +
    "RUN echo \\\n" +
    "# comment\n" +
    "\n" +
    "# comment\n" +
    "\"Hello\"";
let dockerfile = DockerfileParser.parse(
    content
);
let instruction = dockerfile.getInstructions()[1];
for (const a of instruction.getArguments()) {
    console.log(a);
}

Argument {
  value: 'echo',
  range:
   { start: { line: 1, character: 4 },
     end: { line: 1, character: 8 } } }
Argument {
  value: '#',
  range:
   { start: { line: 4, character: 0 },
     end: { line: 4, character: 1 } } }
Argument {
  value: 'comment',
  range:
   { start: { line: 4, character: 2 },
     end: { line: 4, character: 9 } } }
Argument {
  value: '"Hello"',
  range:
   { start: { line: 5, character: 0 },
     end: { line: 5, character: 7 } } }

[rcjsuen]

From further testing, it looks like one comment is okay but multiple comments become a problem.