ci(appveyor): run tests in hatch environment

.appveyor.yml

@@ -322,12 +322,7 @@ for:
           export TMPDIR=/crippledfs
         fi
       - echo TMPDIR=$TMPDIR
-      # run tests on installed module, not source tree files
-      - mkdir __testhome__
-      # run tests on installed module, not source tree files
-      - |
-        cd __testhome__
-        hatch test --durations 20 -m "not (turtle)" -k "$KEYWORDS" --cov=datalad_next --cov datalad --cov-config=../.coveragerc --pyargs ${DTS}
+      - hatch test --cover --doctest-modules --durations 20 -m "not (turtle)" -k "$KEYWORDS"  --pyargs ${DTS}
 
     after_test:
       - python -m coverage xml
@@ -390,11 +385,8 @@ for:
       - tools\appveyor\verify-ssh-access
 
     test_script:
-      # run tests on installed module, not source tree files
-      - cmd: md __testhome__
-      - cmd: cd __testhome__
-        # run test selection
-      - cmd: hatch test --durations 20 -m "not (turtle)" -k "%KEYWORDS%" --cov=datalad_next --cov-config=..\.coveragerc --pyargs %DTS%
+      # run test selection
+      - cmd: hatch test --cover --doctest-modules --durations 20 -m "not (turtle)" -k "%KEYWORDS%"  --pyargs %DTS%
 
     after_test:
       - cmd: python -m coverage xml

pyproject.toml

@@ -94,6 +94,9 @@ extra-dependencies = [
   "webdavclient3",
   "wsgidav",
 ]
+[tool.hatch.envs.hatch-test.env-vars]
+# load the extention
+DATALAD_EXTENSIONS_LOAD = "next"
 
 [tool.hatch.envs.tests]
 description = "run tests across Python versions"