Docker will checkout PR if being run during PR CI

.github/workflows/ci_test_docker.yml

@@ -4,6 +4,8 @@ on: [pull_request,workflow_dispatch]
 
 env:
   TEST_TAG: dtcenter/ccpp-scm:test
+  PR_NUMBER: ${{ github.event.number }}
+
 
 jobs:
   docker:
@@ -26,4 +28,7 @@ jobs:
         run: |
           mkdir $HOME/output
           chmod a+rw $HOME/output
-          docker run --rm -v $HOME/output:/home ${{ env.TEST_TAG }} ./run_scm.py -f ../../test/rt_test_cases.py --runtime_mult 0.1 -d -a
+          docker run \
+                   -e PR_NUMBER="${PR_NUMBER}" \
+                   --rm -v $HOME/output:/home ${{ env.TEST_TAG }} \
+                   ./run_scm.py -f ../../test/rt_test_cases.py --runtime_mult 0.1 -d -a

docker/Dockerfile

@@ -70,11 +70,20 @@ ENV sp_ROOT=/comsoftware/nceplibs
 ENV w3emc_ROOT=/comsoftware/nceplibs
 
 # Obtain CCPP SCM source code, build code, and download static data
-RUN cd /comsoftware \
-  && git clone --recursive -b main https://github.com/NCAR/ccpp-scm \
-  && mkdir /comsoftware/ccpp-scm/scm/bin
-
-RUN cd /comsoftware/ccpp-scm/scm/bin \
+RUN if [ -z "$PR_NUMBER" ]; then \
+        cd /comsoftware \
+        && git clone --recursive -b main https://github.com/NCAR/ccpp-scm; \
+    else \
+        cd /comsoftware \
+        && git clone https://github.com/NCAR/ccpp-scm \
+        && cd ccpp-scm \
+        && git checkout origin pull/${PR_NUMBER}/head:test_pr \
+        && git checkout test_pr \
+        && git submodule update --init --recursive; \
+    fi
+
+RUN mkdir /comsoftware/ccpp-scm/scm/bin \
+  && cd /comsoftware/ccpp-scm/scm/bin \
   && cmake ../src \
   && make -j