docker images --filter=reference giving seemingly unpredictable results

Description

Having read https://github.com/docker/cli/issues/625, I've tried using docker images --filter=reference= with various permutations of repository name, tag and wildcards … and the results seem to be a bit unpredictable. I'm not sure if it is me, the documentation or the software.

Steps to reproduce the issue:

1. Run docker images first of all to get a list of all of the images on the system.
2. Try docker images --filter reference="*:latest" as suggested by issue 625.
3. Try docker images --filter reference='linaroits*:CON*' as a wildcard filter.
4. Try docker images --filter reference='*:*18*' as a wildcard filter.
5. Try docker images --filter reference='*:*18' as a wildcard filter.
6. Try docker images --filter reference='*:CON*' as a wildcard filter.
7. Try docker images --filter reference='*:*CON*' as a wildcard filter.

Describe the results you received:

$ docker images
REPOSITORY                  TAG                 IMAGE ID            CREATED             SIZE
linaroits/jekyllsitebuild   CON-JBC-JOB1-22     44360d759a69        4 days ago          633 MB
linaroits/jekyllsitebuild   latest              44360d759a69        4 days ago          633 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-21     e01c7c71e91b        4 days ago          633 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-19     2b0eca716029        2 weeks ago         633 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-20     2b0eca716029        2 weeks ago         633 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-18     7d8401025378        3 weeks ago         632 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-17     9ea9abcb0b95        3 weeks ago         632 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-16     1e6a32a8b36d        3 weeks ago         632 MB
linaroits/jekyllsitebuild   CON-JBC-JOB1-15     42602caf4124        3 weeks ago         632 MB
linaroits/odpdocsbuild      latest              9264947a316c        3 weeks ago         1.14 GB

$ docker images --filter=reference="*:latest"
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

$ docker images --filter=reference='linaroits*:CON*'
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

$ docker images --filter=reference="*:*18*"
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu              18.04               735f80812f90        5 weeks ago         83.5 MB

$ docker images --filter=reference="*:*18"
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

$ docker images --filter=reference="*:CON*"
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

$ docker images --filter=reference="*:*CON*"
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

Describe the results you expected:

2. I would have expected the two images with a tag of latest to be listed.

3. I would have expected the 8 images with a repository starting linaroits and a tag starting CON to be listed.

4. I would have expected linaroits/jekyllsitebuild:CON-JBC-JOB1-18 to be included in the output.

5. I would have expected linaroits/jekyllsitebuild:CON-JBC-JOB1-18 to be included in the output.

6. I would have expected all images with a tag starting CON to be listed.

7. I would have expected all images with CON somewhere in the tag to be listed which, in my case, would be the same output as test 6 would have produced.

Output of docker version:

Client:
 Version:      17.03.2-ce
 API version:  1.27
 Go version:   go1.6.2
 Git commit:   f5ec1e2
 Built:        Thu Jul  5 23:07:48 2018
 OS/Arch:      linux/amd64

Server:
 Version:      17.03.2-ce
 API version:  1.27 (minimum version 1.12)
 Go version:   go1.6.2
 Git commit:   f5ec1e2
 Built:        Thu Jul  5 23:07:48 2018
 OS/Arch:      linux/amd64
 Experimental: false

Output of docker info:

Containers: 0
 Running: 0
 Paused: 0
 Stopped: 0
Images: 72
Server Version: 17.03.2-ce
Storage Driver: aufs
 Root Dir: /srv/docker/aufs
 Backing Filesystem: extfs
 Dirs: 60
 Dirperm1 Supported: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
 Volume: local
 Network: bridge host macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 4ab9917febca54791c5f071a9d1f404867857fcc
runc version: 54296cf40ad8143b62dbcaa1d90e520a2136ddfe
init version: N/A (expected: 949e6facb77383876aeff8a6944dde66b3089574)
Security Options:
 apparmor
 seccomp
  Profile: default
Kernel Version: 4.4.0-1063-aws
Operating System: Ubuntu 16.04.5 LTS
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 7.795 GiB
Name: ip-10-0-0-18
ID: 54YX:6QXI:5QDF:P5FV:M5JS:Y75Z:VNUD:SVEI:MO7N:UVFL:5RRM:G3LZ
Docker Root Dir: /srv/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Experimental: false
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

WARNING: No swap limit support

Additional environment details (AWS, VirtualBox, physical, etc.):
Docker is running on Ubuntu 16.04 AWS EC2 instance.

Start with the docker images command entry point and reproduce the listed --filter=reference commands against images with matching repository and tag patterns. Compare the observed matches with the expected results in the issue; done means wildcard reference filters consistently return the expected images or their documented semantics are clarified.