Gha test only modified charts (#16)

* feat: test only modified charts with unit tests on pull requests

* run only on charts/** changes

* small improvements replicated from jenkins-infra#598

.github/workflows/test.yml

@@ -16,6 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     outputs:
       charts_matrix: ${{ steps.list_modified_charts_with_unit_tests.outputs.modified_charts_with_unit_tests }}
+    name: Find modified charts with unit tests
     steps:
       - uses: actions/checkout@v3
       - id: list_modified_charts_with_unit_tests
@@ -25,38 +26,39 @@ jobs:
         run: |
           if [ "$GITHUB_EVENT_NAME" == "pull_request" ]; then
             # Retrieve the list of modified chart names in the pull request
-            modifiedChartPaths=$(gh pr view ${{ github.event.pull_request.number }} --json files -q '.files[].path' | xargs dirname | cut -d "/" -f1-2 | grep "^charts/" | sort --unique)
+            modifiedChartPaths=$(gh pr view ${{ github.event.pull_request.number }} --json files -q '.files[].path' | xargs dirname | grep "^charts/" | cut -d "/" -f1-2 | sort --unique)
           else
             # Retrieve all charts
-            modifiedChartPaths=$(find . -maxdepth 2 -type d | cut -d "/" -f2-3 | grep "^charts/" | sort --unique)
+            modifiedChartPaths=$(find . -maxdepth 2 -type d | grep "^charts/" | cut -d "/" -f2-3 | sort --unique)
             # TODO: Retrieve only the list of modified chart names in the last commit since the push
           fi
 
           # Keep only modified charts with unit tests
-          modifiedChartsWithUnitTests=()
+          modifiedChartsWithUnitTestsArray=()
           while IFS= read -r chartName; do
               if [ -d "${chartName}/tests" ]; then
-                  modifiedChartsWithUnitTests+=("$(echo $chartName | cut -d '/' -f 2)")
+                  modifiedChartsWithUnitTestsArray+=("$(echo $chartName | cut -d '/' -f 2)")
               fi
           done <<< "$modifiedChartPaths"
+          modifiedChartsWithUnitTests=$(printf "%s\n" "${modifiedChartsWithUnitTestsArray[@]}")
 
+          jsonArray=""
           if [ -n "$modifiedChartsWithUnitTests" ]; then
+            echo "= List of modified charts with unit tests:"
+            echo "$modifiedChartsWithUnitTests"
             # Transform the array into a JSON
-            jsonArray=$(printf "%s\n" "${modifiedChartsWithUnitTests[@]}" | jq --raw-input --slurp 'split("\n") | map(select(length > 0))' | tr -d '\n')
-            jsonContent="{\"chart\": ${jsonArray}}"
-
-            # Store the JSON as step output
-            echo "modified_charts_with_unit_tests=$jsonContent" >> "$GITHUB_OUTPUT"
+            jsonArray=$(echo "$modifiedChartsWithUnitTests" | jq --raw-input --slurp 'split("\n") | map(select(length > 0))' | tr -d '\n')
           else
             echo "= no modified chart with unit tests found."
-            # Store the JSON as step output
-            echo "modified_charts_with_unit_tests=''" >> "$GITHUB_OUTPUT"
           fi
 
+          # Store the JSON as step output
+          echo "modified_charts_with_unit_tests={\"chart\": ${jsonArray}}" >> "$GITHUB_OUTPUT"
   run-unit-tests:
     runs-on: ubuntu-latest
     needs: find-modified-charts-with-unit-tests
     if: ${{ needs.find-modified-charts-with-unit-tests.outputs.charts_matrix != '' }}  # Without it, the strategy parser will fail if the changed_directories is empty.
+    name: Run unit tests
     strategy:
       matrix: ${{fromJson(needs.find-modified-charts-with-unit-tests.outputs.charts_matrix)}}
       fail-fast: false