diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index f3a2bccfc..b1bae1c18 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,8 +1,7 @@
-# evaluating GitHub actions for CI, disconsider failures when evaluating PRs
+# evaluating GitHub actions for CI, disregard failures when evaluating PRs
 #
 # this is still missing:
 # - deploy
-# - coverage
 # - upload github notes
 #
 name: main
@@ -17,7 +16,6 @@ on:
 
 jobs:
   build:
-
     runs-on: ${{ matrix.os }}
 
     strategy:
@@ -86,6 +84,8 @@ jobs:
             python: "3.7"
             os: ubuntu-latest
             tox_env: "py37-freeze"
+            # coverage does not apply for freeze test, skip it
+            skip_coverage: true
           - name: "ubuntu-py38"
             python: "3.8"
             os: ubuntu-latest
@@ -94,6 +94,8 @@ jobs:
             python: "pypy3"
             os: ubuntu-latest
             tox_env: "pypy3-xdist"
+            # coverage too slow with pypy3, skip it
+            skip_coverage: true
 
           - name: "macos-py37"
             python: "3.7"
@@ -118,6 +120,37 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install tox
-    - name: Test
-      run: tox -e ${{ matrix.tox_env }}
+        pip install tox coverage
+
+    - name: Test without coverage
+      if: "matrix.skip_coverage"
+      run: "tox -e ${{ matrix.tox_env }}"
+
+    - name: Test with coverage
+      if: "! matrix.skip_coverage"
+      env:
+        _PYTEST_TOX_COVERAGE_RUN: "coverage run -m"
+        COVERAGE_PROCESS_START: ".coveragerc"
+        _PYTEST_TOX_EXTRA_DEP: "coverage-enable-subprocess"
+      run: "tox -e ${{ matrix.tox_env }}"
+
+    - name: Prepare coverage token
+      if: success() && !matrix.skip_coverage && ( github.repository == 'pytest-dev/pytest' || github.event_name == 'pull_request' )
+      run: |
+        python scripts/append_codecov_token.py
+
+    - name: Combine coverage
+      if: success() && !matrix.skip_coverage
+      run: |
+        python -m coverage combine
+        python -m coverage xml
+
+    - name: Codecov upload
+      if: success() && !matrix.skip_coverage
+      uses: codecov/codecov-action@v1
+      with:
+        token: ${{ secrets.codecov }}
+        file: ./coverage.xml
+        flags: ${{ runner.os }}
+        fail_ci_if_error: false
+        name: ${{ matrix.name }}
diff --git a/.travis.yml b/.travis.yml
index 35ca8a69c..5b67f15dd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -52,8 +52,10 @@ jobs:
     - env: TOXENV=pypy3-xdist
       python: 'pypy3'
 
-    - env: TOXENV=py35-xdist
-      python: '3.5'
+    # Coverage for Python 3.5.{0,1} specific code, mostly typing related.
+    - env: TOXENV=py35 PYTEST_COVERAGE=1 PYTEST_ADDOPTS="-k test_raises_cyclic_reference"
+      python: '3.5.1'
+      dist: trusty
 
     # Specialized factors for py37.
     - env: TOXENV=py37-pluggymaster-xdist
diff --git a/scripts/append_codecov_token.py b/scripts/append_codecov_token.py
new file mode 100644
index 000000000..8eecb0fa5
--- /dev/null
+++ b/scripts/append_codecov_token.py
@@ -0,0 +1,36 @@
+"""
+Appends the codecov token to the 'codecov.yml' file at the root of the repository.
+
+This is done by CI during PRs and builds on the pytest-dev repository so we can upload coverage, at least
+until codecov grows some native integration like it has with Travis and AppVeyor.
+
+See discussion in https://github.com/pytest-dev/pytest/pull/6441 for more information.
+"""
+import os.path
+from textwrap import dedent
+
+
+def main():
+    this_dir = os.path.dirname(__file__)
+    cov_file = os.path.join(this_dir, "..", "codecov.yml")
+
+    assert os.path.isfile(cov_file), "{cov_file} does not exist".format(
+        cov_file=cov_file
+    )
+
+    with open(cov_file, "a") as f:
+        # token from: https://codecov.io/gh/pytest-dev/pytest/settings
+        # use same URL to regenerate it if needed
+        text = dedent(
+            """
+            codecov:
+              token: "1eca3b1f-31a2-4fb8-a8c3-138b441b50a7"
+        """
+        )
+        f.write(text)
+
+    print("Token updated:", cov_file)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/src/_pytest/compat.py b/src/_pytest/compat.py
index c566a39e8..9eec0aeda 100644
--- a/src/_pytest/compat.py
+++ b/src/_pytest/compat.py
@@ -382,7 +382,7 @@ class CaptureAndPassthroughIO(CaptureIO):
         return self._other.write(s)
 
 
-if sys.version_info < (3, 5, 2):  # pragma: no cover
+if sys.version_info < (3, 5, 2):
 
     def overload(f):  # noqa: F811
         return f
diff --git a/src/_pytest/config/findpaths.py b/src/_pytest/config/findpaths.py
index f06c9cfff..728246dfc 100644
--- a/src/_pytest/config/findpaths.py
+++ b/src/_pytest/config/findpaths.py
@@ -108,7 +108,7 @@ CFG_PYTEST_SECTION = "[pytest] section in {filename} files is no longer supporte
 
 
 def determine_setup(
-    inifile: str,
+    inifile: Optional[str],
     args: List[str],
     rootdir_cmd_arg: Optional[str] = None,
     config: Optional["Config"] = None,
diff --git a/testing/python/raises.py b/testing/python/raises.py
index 1c701796a..cfdbe6748 100644
--- a/testing/python/raises.py
+++ b/testing/python/raises.py
@@ -166,7 +166,7 @@ class TestRaises:
                 # Early versions of Python 3.5 have some bug causing the
                 # __call__ frame to still refer to t even after everything
                 # is done. This makes the test pass for them.
-                if sys.version_info < (3, 5, 2):  # pragma: no cover
+                if sys.version_info < (3, 5, 2):
                     del self
                 raise ValueError
 
diff --git a/testing/test_config.py b/testing/test_config.py
index 9735fc176..29bd45c6c 100644
--- a/testing/test_config.py
+++ b/testing/test_config.py
@@ -859,7 +859,7 @@ class TestRootdir:
             assert get_common_ancestor([no_path.join("a")]) == tmpdir
 
     @pytest.mark.parametrize("name", "setup.cfg tox.ini pytest.ini".split())
-    def test_with_ini(self, tmpdir, name):
+    def test_with_ini(self, tmpdir, name) -> None:
         inifile = tmpdir.join(name)
         inifile.write("[pytest]\n" if name != "setup.cfg" else "[tool:pytest]\n")
 
@@ -874,7 +874,7 @@ class TestRootdir:
         assert inifile == inifile
 
     @pytest.mark.parametrize("name", "setup.cfg tox.ini".split())
-    def test_pytestini_overrides_empty_other(self, tmpdir, name):
+    def test_pytestini_overrides_empty_other(self, tmpdir, name) -> None:
         inifile = tmpdir.ensure("pytest.ini")
         a = tmpdir.mkdir("a")
         a.ensure(name)
@@ -882,7 +882,7 @@ class TestRootdir:
         assert rootdir == tmpdir
         assert inifile == inifile
 
-    def test_setuppy_fallback(self, tmpdir):
+    def test_setuppy_fallback(self, tmpdir) -> None:
         a = tmpdir.mkdir("a")
         a.ensure("setup.cfg")
         tmpdir.ensure("setup.py")
@@ -891,14 +891,14 @@ class TestRootdir:
         assert inifile is None
         assert inicfg == {}
 
-    def test_nothing(self, tmpdir, monkeypatch):
+    def test_nothing(self, tmpdir, monkeypatch) -> None:
         monkeypatch.chdir(str(tmpdir))
         rootdir, inifile, inicfg = determine_setup(None, [tmpdir])
         assert rootdir == tmpdir
         assert inifile is None
         assert inicfg == {}
 
-    def test_with_specific_inifile(self, tmpdir):
+    def test_with_specific_inifile(self, tmpdir) -> None:
         inifile = tmpdir.ensure("pytest.ini")
         rootdir, inifile, inicfg = determine_setup(inifile, [tmpdir])
         assert rootdir == tmpdir
@@ -1039,7 +1039,7 @@ class TestOverrideIniArgs:
         result = testdir.runpytest("--override-ini", "python_files=unittest_*.py")
         result.stdout.fnmatch_lines(["*1 passed in*"])
 
-    def test_with_arg_outside_cwd_without_inifile(self, tmpdir, monkeypatch):
+    def test_with_arg_outside_cwd_without_inifile(self, tmpdir, monkeypatch) -> None:
         monkeypatch.chdir(str(tmpdir))
         a = tmpdir.mkdir("a")
         b = tmpdir.mkdir("b")
@@ -1047,7 +1047,7 @@ class TestOverrideIniArgs:
         assert rootdir == tmpdir
         assert inifile is None
 
-    def test_with_arg_outside_cwd_with_inifile(self, tmpdir):
+    def test_with_arg_outside_cwd_with_inifile(self, tmpdir) -> None:
         a = tmpdir.mkdir("a")
         b = tmpdir.mkdir("b")
         inifile = a.ensure("pytest.ini")
@@ -1056,13 +1056,13 @@ class TestOverrideIniArgs:
         assert inifile == parsed_inifile
 
     @pytest.mark.parametrize("dirs", ([], ["does-not-exist"], ["a/does-not-exist"]))
-    def test_with_non_dir_arg(self, dirs, tmpdir):
+    def test_with_non_dir_arg(self, dirs, tmpdir) -> None:
         with tmpdir.ensure(dir=True).as_cwd():
             rootdir, inifile, inicfg = determine_setup(None, dirs)
             assert rootdir == tmpdir
             assert inifile is None
 
-    def test_with_existing_file_in_subdir(self, tmpdir):
+    def test_with_existing_file_in_subdir(self, tmpdir) -> None:
         a = tmpdir.mkdir("a")
         a.ensure("exist")
         with tmpdir.as_cwd():
diff --git a/tox.ini b/tox.ini
index d33a62224..c26b7cf82 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,7 +26,7 @@ passenv = USER USERNAME COVERAGE_* TRAVIS PYTEST_ADDOPTS TERM
 setenv =
     _PYTEST_TOX_DEFAULT_POSARGS={env:_PYTEST_TOX_POSARGS_LSOF:} {env:_PYTEST_TOX_POSARGS_XDIST:}
 
-    # Configuration to run with coverage similar to Travis/Appveyor, e.g.
+    # Configuration to run with coverage similar to CI, e.g.
     # "tox -e py37-coverage".
     coverage: _PYTEST_TOX_COVERAGE_RUN=coverage run -m
     coverage: _PYTEST_TOX_EXTRA_DEP=coverage-enable-subprocess
@@ -53,7 +53,7 @@ deps =
 skip_install = True
 basepython = python3
 deps = pre-commit>=1.11.0
-commands = pre-commit run --all-files --show-diff-on-failure
+commands = pre-commit run --all-files --show-diff-on-failure {posargs:}
 
 [testenv:docs]
 basepython = python3