ci: codecov: use gcovr and upload cobertura style file

Use gcovr to generate reports and upload cobertura style file instead of
previously lcov info file.

We have been seeing issues with lcov format and code being reporting as
not covered although by inspecting the generate output files, they
should be.

The XML format we generate is otherwise easier to parse and deal with.

Also reduce frequency to twice a day.

Fixes #66656

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

.github/workflows/codecov.yaml

@@ -2,7 +2,7 @@ name: Code Coverage with codecov
 
 on:
   schedule:
-    - cron: '25 */3 * * 1-5'
+    - cron: '25 06,18 * * 1-5'
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event_name }}-${{ github.head_ref || github.ref }}
@@ -88,27 +88,25 @@ jobs:
           export ZEPHYR_BASE=${PWD}
           export ZEPHYR_TOOLCHAIN_VARIANT=zephyr
           mkdir -p coverage/reports
-          ./scripts/twister --force-color -N -v --filter runnable -p ${{ matrix.platform }} --coverage -T tests
-
-      - name: Generate Coverage Report
-        run: |
-          mv twister-out/coverage.info lcov.pre.info
-          lcov -q --remove lcov.pre.info mylib.c --remove lcov.pre.info tests/\* \
-            --remove lcov.pre.info samples/\* --remove lcov.pre.info ext/\* \
-            --remove lcov.pre.info *generated*  \
-            -o coverage/reports/${{ matrix.platform }}.info --rc lcov_branch_coverage=1
+          pip3 install gcovr
+          ./scripts/twister -i --force-color -N -v --filter runnable -p ${{ matrix.platform }} --coverage -T tests --coverage-tool gcovr
 
       - name: ccache stats post
         run: |
           ccache -s
           ccache -p
 
+      - name: Rename coverage files
+        if: always()
+        run: |
+          cp twister-out/coverage.json coverage/reports/${{ matrix.platform }}.json
+
       - name: Upload Coverage Results
         if: always()
         uses: actions/upload-artifact@v3
         with:
           name: Coverage Data (Subset ${{ matrix.platform }})
-          path: coverage/reports/${{ matrix.platform }}.info
+          path: coverage/reports/${{ matrix.platform }}.json
 
   codecov-results:
     name: "Publish Coverage Results"
@@ -129,14 +127,14 @@ jobs:
 
       - name: Move coverage files
         run: |
-          mv ./coverage/reports/*/*.info ./coverage/reports
+          mv ./coverage/reports/*/*.json ./coverage/reports
           ls -la ./coverage/reports
 
       - name: Generate list of coverage files
         id: get-coverage-files
         shell: cmake -P {0}
         run: |
-          file(GLOB INPUT_FILES_LIST  "coverage/reports/*.info")
+          file(GLOB INPUT_FILES_LIST  "coverage/reports/*.json")
           set(MERGELIST "")
           set(FILELIST "")
           foreach(ITEM ${INPUT_FILES_LIST})
@@ -150,7 +148,7 @@ jobs:
           foreach(ITEM ${INPUT_FILES_LIST})
             get_filename_component(f ${ITEM} NAME)
             if(MERGELIST STREQUAL "")
-              set(MERGELIST "-a ${f}")
+              set(MERGELIST "--add-tracefile ${f}")
             else()
               set(MERGELIST "${MERGELIST} -a ${f}")
             endif()
@@ -160,17 +158,19 @@ jobs:
 
       - name: Merge coverage files
         run: |
-          sudo apt-get update
-          sudo apt-get install -y lcov
           cd ./coverage/reports
-          lcov ${{ steps.get-coverage-files.outputs.mergefiles }} -o merged.info --rc lcov_branch_coverage=1
+          pip3 install gcovr
+          gcovr ${{ steps.get-coverage-files.outputs.mergefiles }}  --merge-mode-functions=separate --json merged.json
+          gcovr ${{ steps.get-coverage-files.outputs.mergefiles }} --merge-mode-functions=separate --cobertura merged.xml
 
       - name: Upload Merged Coverage Results
         if: always()
         uses: actions/upload-artifact@v3
         with:
           name: Merged Coverage Data
-          path: merged.info
+          path: |
+            coverage/reports/merged.json
+            coverage/reports/merged.xml
 
       - name: Upload coverage to Codecov
         if: always()
@@ -180,4 +180,4 @@ jobs:
           env_vars: OS,PYTHON
           fail_ci_if_error: false
           verbose: true
-          files: merged.info
+          files: merged.xml