Stabilize and handle releases

Dockerfile

@@ -1,4 +1,4 @@
-FROM docker
+FROM docker as runtime
 LABEL "com.github.actions.name"="Publish Docker"
 LABEL "com.github.actions.description"="Uses the git branch as the docker tag and pushes the container"
 LABEL "com.github.actions.icon"="anchor"
@@ -13,3 +13,12 @@ RUN apk update \
 
 ADD entrypoint.sh /entrypoint.sh
 ENTRYPOINT ["/entrypoint.sh"]
+
+FROM runtime as test
+ADD test.sh /test.sh
+ADD mock.sh /fake_bin/docker
+# Use mock instead of real docker
+ENV PATH="/bin:/fake_bin"
+RUN /test.sh
+
+FROM runtime

entrypoint.sh

@@ -1,10 +1,15 @@
-#!/bin/sh -l
+#!/bin/sh
 
 DOCKER_REPOSITORY=$*
-
 BRANCH=$(echo ${GITHUB_REF} | sed -e "s/refs\/heads\///g")
+
 if [ "${BRANCH}" = "master" ]; then
-    BRANCH="latest"
+  BRANCH="latest"
+fi;
+
+# if contains /refs/tags/
+if [ $(echo ${GITHUB_REF} | sed -e "s/refs\/tags\///g") != ${GITHUB_REF} ]; then
+  BRANCH="latest"
 fi;
 
 DOCKERNAME="${DOCKER_REPOSITORY}:${BRANCH}"

mock.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+echo "Called mock with: $@"
+exit 0

test.sh

@@ -0,0 +1,41 @@
+#!/bin/sh -e
+
+function itPushesMasterBranchToLatest() {
+  export GITHUB_REF='refs/heads/master'
+  result=$(exec /entrypoint.sh 'my/repository')
+  expected="Called mock with: build -t my/repository:latest .
+Called mock with: push my/repository:latest"
+  if [ "$result" != "$expected" ]; then
+    echo "Expected: $expected
+    Got: $result"
+    exit 1
+  fi
+}
+
+function itPushesBranchAsNameOfTheBranch() {
+  export GITHUB_REF='refs/heads/myBranch'
+  result=$(exec /entrypoint.sh 'my/repository')
+  expected="Called mock with: build -t my/repository:myBranch .
+Called mock with: push my/repository:myBranch"
+  if [ "$result" != "$expected" ]; then
+    echo "Expected: $expected
+    Got: $result"
+    exit 1
+  fi
+}
+
+function itPushesReleasesToLatest() {
+  export GITHUB_REF='refs/tags/myRelease'
+  result=$(exec /entrypoint.sh 'my/repository')
+  expected="Called mock with: build -t my/repository:latest .
+Called mock with: push my/repository:latest"
+  if [ "$result" != "$expected" ]; then
+    echo "Expected: $expected
+    Got: $result"
+    exit 1
+  fi
+}
+
+itPushesMasterBranchToLatest
+itPushesBranchAsNameOfTheBranch
+itPushesReleasesToLatest