try codecov action

.github/workflows/codecov.yml

@@ -0,0 +1,22 @@
+name: Run tests
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 2
+      - name: Install dependencies
+        run: yarn install
+      - name: Run tests
+        run: yarn run test --coverage # generates coverage
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v2
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          fail_ci_if_error: true
+          verbose: true

README.md

@@ -8,6 +8,7 @@ AlgoPlus is a C++ library that includes ready to use complex Data Structures.
 [![CodeQL CI](https://github.com/TheAlgorithms/C-Plus-Plus/actions/workflows/codeql.yml/badge.svg)](https://github.com/CSRT-NTUA/AlgoPlus/actions/workflows/codeql.yml)
 [![Awesome CI](https://github.com/CSRT-NTUA/AlgoPlus/workflows/Awesome%20CI%20Workflow/badge.svg)](https://github.com/CSRT-NTUA/AlgoPlus/actions?query=workflow%3A%22Awesome+CI+Workflow%22)
 ![GitHub repo size](https://img.shields.io/github/repo-size/CSRT-NTUA/AlgoPlus)
+[![codecov](https://codecov.io/gh/CSRT-NTUA/AlgoPlus/graph/badge.svg?token=3SBDRHUQR5)](https://codecov.io/gh/CSRT-NTUA/AlgoPlus)
 
 ### **See the full documentation [here](https://csrt-ntua.github.io/AlgoPlus/)**