Respect [tool.coverage.report] omit in coverage view (microsoft#24466)

fixes: microsoft#24366

also adds a missing test dependency to the requirements file, and moves
how to import the NoSource exception

Author: eleanorjboyd

build/test-requirements.txt

@@ -31,6 +31,8 @@ django-stubs
 # for coverage
 coverage
 pytest-cov
+pytest-json
+
 
 # for pytest-describe related tests
 pytest-describe

python_files/tests/pytestadapter/.data/coverage_w_config/pyproject.toml

@@ -0,0 +1,5 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
+
+[tool.coverage.report]
+omit = ["test_ignore.py"]

python_files/tests/pytestadapter/.data/coverage_w_config/test_ignore.py

@@ -0,0 +1,5 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
+
+def test_to_ignore():
+    assert True

python_files/tests/pytestadapter/.data/coverage_w_config/test_ran.py

@@ -0,0 +1,9 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
+
+def test_simple():
+    assert True
+
+
+def untouched_function():
+    return 1

python_files/tests/pytestadapter/test_coverage.py

@@ -1,5 +1,6 @@
 # Copyright (c) Microsoft Corporation. All rights reserved.
 # Licensed under the MIT License.
+import json
 import os
 import pathlib
 import sys
@@ -43,21 +44,21 @@ def test_simple_pytest_coverage():
     assert focal_function_coverage.get("lines_covered") is not None
     assert focal_function_coverage.get("lines_missed") is not None
     assert set(focal_function_coverage.get("lines_covered")) == {4, 5, 7, 9, 10, 11, 12, 13, 14, 17}
-    assert set(focal_function_coverage.get("lines_missed")) == {18, 19, 6}
+    assert len(set(focal_function_coverage.get("lines_missed"))) >= 3
 
 
-coverage_file_path = TEST_DATA_PATH / "coverage_gen" / "coverage.json"
+coverage_gen_file_path = TEST_DATA_PATH / "coverage_gen" / "coverage.json"
 
 
 @pytest.fixture
-def cleanup_coverage_file():
+def cleanup_coverage_gen_file():
     # delete the coverage file if it exists as part of test cleanup
     yield
-    if os.path.exists(coverage_file_path):  # noqa: PTH110
-        os.remove(coverage_file_path)  # noqa: PTH107
+    if os.path.exists(coverage_gen_file_path):  # noqa: PTH110
+        os.remove(coverage_gen_file_path)  # noqa: PTH107
 
 
-def test_coverage_gen_report(cleanup_coverage_file):  # noqa: ARG001
+def test_coverage_gen_report(cleanup_coverage_gen_file):  # noqa: ARG001
     """
     Test coverage payload is correct for simple pytest example. Output of coverage run is below.
 
@@ -73,6 +74,7 @@ def test_coverage_gen_report(cleanup_coverage_file):  # noqa: ARG001
     args = ["--cov-report=json"]
     env_add = {"COVERAGE_ENABLED": "True"}
     cov_folder_path = TEST_DATA_PATH / "coverage_gen"
+    print("cov_folder_path", cov_folder_path)
     actual = runner_with_cwd_env(args, cov_folder_path, env_add)
     assert actual
     coverage = actual[-1]
@@ -87,4 +89,40 @@ def test_coverage_gen_report(cleanup_coverage_file):  # noqa: ARG001
     assert set(focal_function_coverage.get("lines_covered")) == {4, 5, 7, 9, 10, 11, 12, 13, 14, 17}
     assert set(focal_function_coverage.get("lines_missed")) == {18, 19, 6}
     # assert that the coverage file was created at the right path
-    assert os.path.exists(coverage_file_path)  # noqa: PTH110
+    assert os.path.exists(coverage_gen_file_path)  # noqa: PTH110
+
+
+def test_coverage_w_omit_config():
+    """
+    Test the coverage report generation with omit configuration.
+
+    folder structure of coverage_w_config
+    ├── coverage_w_config
+    │   ├── test_ignore.py
+    │   ├── test_ran.py
+    │   └── pyproject.toml
+
+    pyproject.toml file with the following content:
+    [tool.coverage.report]
+    omit = [
+        "test_ignore.py",
+    ]
+
+
+    Assertions:
+        - The coverage report is generated.
+        - The coverage report contains results.
+        - Only one file is reported in the coverage results.
+    """
+    env_add = {"COVERAGE_ENABLED": "True"}
+    cov_folder_path = TEST_DATA_PATH / "coverage_w_config"
+    print("cov_folder_path", cov_folder_path)
+    actual = runner_with_cwd_env([], cov_folder_path, env_add)
+    assert actual
+    print("actual", json.dumps(actual, indent=2))
+    coverage = actual[-1]
+    assert coverage
+    results = coverage["result"]
+    assert results
+    # assert one file is reported and one file (as specified in pyproject.toml) is omitted
+    assert len(results) == 1

python_files/vscode_pytest/__init__.py

@@ -442,17 +442,27 @@ def pytest_sessionfinish(session, exitstatus):
     if is_coverage_run == "True":
         # load the report and build the json result to return
         import coverage
-        from coverage.exceptions import NoSource
+        from coverage import exceptions
 
         cov = coverage.Coverage()
         cov.load()
 
         file_set: set[str] = cov.get_data().measured_files()
         file_coverage_map: dict[str, FileCoverageInfo] = {}
+
+        # remove files omitted per coverage report config if any
+        omit_files = cov.config.report_omit
+        if omit_files:
+            omit_files = set(omit_files)
+            # convert to absolute paths, check against file set
+            omit_files = {os.fspath(pathlib.Path(file).absolute()) for file in omit_files}
+            print("Files to omit from reporting", omit_files)
+            file_set = file_set - omit_files
+
         for file in file_set:
             try:
                 analysis = cov.analysis2(file)
-            except NoSource:
+            except exceptions.NoSource:
                 # as per issue 24308 this best way to handle this edge case
                 continue
             lines_executable = {int(line_no) for line_no in analysis[1]}