Revert build-esp32-idf (removed by mistake)

.github/workflows/tests.yml

@@ -210,3 +210,32 @@ jobs:
       run: |
         cd platforms/arduino
         pio run -e tinyBLE
+
+  build-esp32-idf:
+    runs-on: ubuntu-latest
+    container: igrr/idf-qemu:release-v4.0-esp-develop-20191228
+    timeout-minutes: 5
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: Build for ESP32 (IDF v4.0)
+      run: |
+        . $IDF_PATH/export.sh
+        cd platforms/esp32-idf
+        export EXTRA_CFLAGS="-Werror"
+        idf.py build
+      shell: bash
+    - name: Test for ESP32 in QEMU
+      run: |
+        cd platforms/esp32-idf
+        make-flash-img.sh wasm3 flash_img.bin
+        qemu-system-xtensa -machine esp32 -nographic -drive file=flash_img.bin,if=mtd,format=raw -no-reboot | tee out.txt
+        grep "wasm3 on ESP32, build " out.txt
+        grep "Result: 46368" out.txt
+        grep "Elapsed: " out.txt
+        grep "Restarting..." out.txt
+        test $(($(grep "ets Jun  8 2016" out.txt | wc -l))) -eq 1
+    - name: Check that IDF and PIO examples are in sync
+      run: |
+        diff -q platforms/esp32-idf/main/main.cpp platforms/esp32-pio/src/main.cpp
+      # TODO: also check that the build flags are in sync