Ignoring subfolders not working - docker

Question

I'm using a .dockerignore file that looks like this:
*
*/node_modules
*/bower_components
!www
!app
!inc
so here what I'm saying is: ignore all files in the current directory (this post is related to: How to include local libraries in build?) except for www, app and inc and ignore all directories named node_modules and bower_components in those subdirectories
when I run a build:
build --no-cache -t test -f app/Dockerfile .
(here's my Dockerfile):
FROM node:latest
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
ADD . /usr/src/app/
and then run a container:
run -i --entrypoint=/bin/bash test
if I look in the directory I see node_modules folders!
# ls -alF
total 20
drwxr-xr-x 5 root root 4096 Mar 19 03:39 ./
drwxr-xr-x 4 root root 4096 Mar 19 03:39 ../
drwxr-xr-x 4 root root 4096 Mar 18 03:26 inc/
drwxr-xr-x 3 root root 4096 Mar 19 00:57 app/
drwxr-xr-x 12 root root 4096 Mar 18 08:55 www/
# ls -alF app
total 36
drwxr-xr-x 3 root root 4096 Mar 19 00:57 ./
drwxr-xr-x 5 root root 4096 Mar 19 03:39 ../
-rw-r--r-- 1 root root 38 Mar 19 00:57 .dockerignore
-rw-r--r-- 1 root root 359 Mar 19 03:37 Dockerfile
-rw-r--r-- 1 root root 700 Mar 18 04:50 config.json
-rw-r--r-- 1 root root 3786 Mar 18 03:43 index.js
drwxr-xr-x 119 root root 4096 Mar 17 18:57 node_modules/
-rw-r--r-- 1 root root 2910 Mar 17 20:51 npm-debug.log
-rw-r--r-- 1 root root 348 Mar 19 03:24 package.json
so the first line of the .dockerignore worked fine, as did the 4th, 5th and 6th lines, but the subdirectories failed. for the sake of completeness I originally used **/node_modules but that failed too.
what is the correct way of expressing this?

Answer 1

ok, apparently the problem is that when I create exceptions to the ignore rules, I have to reapply the exceptions, so if I do this instead:
*
!www
!app
!inc
*/node_modules
*/bower_components
it works because */node_modules applies to "all of the above", which includes app. in my original declaration I was excluding the directories I do want to include from the rules