Add expand_coverage_report option to for #270

.gitignore

@@ -4,6 +4,7 @@
 .idea
 venv
 27venv
+.venv
 
 # C extensions
 *.so

README.rst

@@ -274,6 +274,18 @@ It can be enabled by using the ``-q``/``--quiet`` flag:
 
 If enabled, the tool will only print errors and failures but no information or warning messages.
 
+Compatibility with multi-line statements 
+----------
+``diff-cover`` relies on the comparison of diff reports and coverage reports, and does not report
+lines that appear in one and not in the other. While diff reports list all lines that changed,
+coverage reports usually list code statements. As a result, a change in a multi-line statement may not be analyzed by ``diff-cover``.
+
+As a workaround, you can use the argument ``--expand-coverage-report``: lines not appearing in the coverage reports will be added to them with the same number of hits as the previously reported line. ``diff-cover`` will then perform diff coverage analysis on all changed lines.
+
+Notes:
+- This argument is only available for XML coverage reports.
+- This workaround is designed under the assumption that the coverage tool reports untested statements with hits set to 0, and it reports statements based on the opening line. 
+
 Configuration files
 -------------------
 Both tools allow users to specify the options in a configuration file with `--config-file`/`-c`:

diff_cover/diff_cover_tool.py

@@ -41,6 +41,9 @@
 )
 QUIET_HELP = "Only print errors and failures"
 SHOW_UNCOVERED = "Show uncovered lines on the console"
+EXPAND_COVERAGE_REPORT = (
+ "Append missing lines in coverage reports based on the hits of the previous line."
+)
 INCLUDE_UNTRACKED_HELP = "Include untracked files"
 CONFIG_FILE_HELP = "The configuration file to use"
 DIFF_FILE_HELP = "The diff file to use"
@@ -93,6 +96,13 @@ def parse_coverage_args(argv):
  "--show-uncovered", action="store_true", default=None, help=SHOW_UNCOVERED
  )
 
+ parser.add_argument(
+ "--expand-coverage-report",
+ action="store_true",
+ default=None,
+ help=EXPAND_COVERAGE_REPORT,
+ )
+
  parser.add_argument(
  "--external-css-file",
  metavar="FILENAME",
@@ -183,6 +193,7 @@ def parse_coverage_args(argv):
  "ignore_whitespace": False,
  "diff_range_notation": "...",
  "quiet": False,
+ "expand_coverage_report": False,
  }
 
  return get_config(parser=parser, argv=argv, defaults=defaults, tool=Tool.DIFF_COVER)
@@ -204,6 +215,7 @@ def generate_coverage_report(
  src_roots=None,
  quiet=False,
  show_uncovered=False,
+ expand_coverage_report=False,
 ):
  """
  Generate the diff coverage report, using kwargs from `parse_args()`.
@@ -231,7 +243,7 @@ def generate_coverage_report(
  if len(xml_roots) > 0 and len(lcov_roots) > 0:
  raise ValueError(f"Mixing LCov and XML reports is not supported yet")
  elif len(xml_roots) > 0:
- coverage = XmlCoverageReporter(xml_roots, src_roots)
+ coverage = XmlCoverageReporter(xml_roots, src_roots, expand_coverage_report)
  else:
  coverage = LcovCoverageReporter(lcov_roots, src_roots)
 
@@ -308,6 +320,7 @@ def main(argv=None, directory=None):
  src_roots=arg_dict["src_roots"],
  quiet=quiet,
  show_uncovered=arg_dict["show_uncovered"],
+ expand_coverage_report=arg_dict["expand_coverage_report"],
  )
 
  if percent_covered >= fail_under:

diff_cover/violationsreporters/violations_reporter.py

@@ -24,7 +24,7 @@ class XmlCoverageReporter(BaseViolationReporter):
  Query information from a Cobertura|Clover|JaCoCo XML coverage report.
  """
 
- def __init__(self, xml_roots, src_roots=None):
+ def __init__(self, xml_roots, src_roots=None, expand_coverage_report=False):
  """
  Load the XML coverage report represented
  by the cElementTree with root element `xml_root`.
@@ -41,6 +41,7 @@ def __init__(self, xml_roots, src_roots=None):
  self._xml_cache = [{} for i in range(len(xml_roots))]
 
  self._src_roots = src_roots or [""]
+ self._expand_coverage_report = expand_coverage_report
 
  def _get_xml_classes(self, xml_document):
  """
@@ -216,6 +217,28 @@ def _cache_file(self, src_path):
  if line_nodes is None:
  continue
 
+ # Expand coverage report with not reported lines
+ if self._expand_coverage_report:
+ reported_line_hits = {}
+ for line in line_nodes:
+ reported_line_hits[int(line.get(_number))] = int(
+ line.get(_hits, 0)
+ )
+ if reported_line_hits:
+ last_hit_number = 0
+ for line_number in range(
+ min(reported_line_hits.keys()),
+ max(reported_line_hits.keys()),
+ ):
+ if line_number in reported_line_hits:
+ last_hit_number = reported_line_hits[line_number]
+ else:
+ # This is an unreported line.
+ # We add it with the previous line hit score
+ line_nodes.append(
+ {_hits: last_hit_number, _number: line_number}
+ )
+
  # First case, need to define violations initially
  if violations is None:
  violations = {

tests/fixtures/coverage_missing_lines.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" ?>
+<!DOCTYPE coverage
+ SYSTEM 'http://cobertura.sourceforge.net/xml/coverage-03.dtd'>
+<coverage branch-rate="0" line-rate="0.8792" timestamp="1371471706873" version="3.6">
+ <packages>
+ <package branch-rate="0" complexity="0" line-rate="0.9915" name="">
+ <classes>
+ <class branch-rate="0" complexity="0" filename="test_src.txt" line-rate="0.9643" name="test_src.txt">
+ <methods/>
+ <lines>
+ <line hits="1" number="1"/>
+ <line hits="0" number="2"/>
+ <line hits="0" number="4"/>
+ <line hits="1" number="5"/>
+ <line hits="1" number="7"/>
+ <line hits="0" number="8"/>
+ <line hits="1" number="9"/>
+ <line hits="0" number="10"/>
+ </lines>
+ </class>
+ </classes>
+ </package>
+ </packages>
+</coverage>

tests/fixtures/expand_console_report.txt

@@ -0,0 +1,10 @@
+-------------
+Diff Coverage
+Diff: origin/main...HEAD, staged and unstaged changes
+-------------
+test_src.txt (50.0%): Missing lines 2-4,8,10
+-------------
+Total: 10 lines
+Missing: 5 lines
+Coverage: 50%
+-------------

tests/test_integration.py

@@ -412,6 +412,20 @@ def test_show_uncovered_lines_console(self):
  ["diff-cover", "--show-uncovered", "coverage.xml"],
  )
 
+ def test_expand_coverage_report_complete_report(self):
+ self._check_console_report(
+ "git_diff_add.txt",
+ "add_console_report.txt",
+ ["diff-cover", "coverage.xml", "--expand-coverage-report"],
+ )
+
+ def test_expand_coverage_report_uncomplete_report(self):
+ self._check_console_report(
+ "git_diff_add.txt",
+ "expand_console_report.txt",
+ ["diff-cover", "coverage_missing_lines.xml", "--expand-coverage-report"],
+ )
+
 
 class TestDiffQualityIntegration(ToolsIntegrationBase):
  """

tests/test_violations_reporter.py

@@ -66,6 +66,21 @@ class TestXmlCoverageReporterTest:
  ONE_VIOLATION = {Violation(11, None)}
  VERY_MANY_MEASURED = {2, 3, 5, 7, 11, 13, 17, 23, 24, 25, 26, 26, 27}
 
+ MANY_VIOLATIONS_EXPANDED_MANY_MEASURED = {
+ Violation(3, None),
+ Violation(4, None),
+ Violation(7, None),
+ Violation(8, None),
+ Violation(9, None),
+ Violation(10, None),
+ Violation(11, None),
+ Violation(12, None),
+ Violation(13, None),
+ Violation(14, None),
+ Violation(15, None),
+ Violation(16, None),
+ }
+
  @pytest.fixture(autouse=True)
  def patch_git_patch(self, mocker):
  # Paths generated by git_path are always the given argument
@@ -266,6 +281,52 @@ def test_no_such_file(self):
  result = coverage.violations("file.py")
  assert result == set()
 
+ def test_expand_unreported_lines_when_configured(self):
+ # Construct the XML report
+ file_paths = ["file1.java"]
+ # fixture
+ violations = self.MANY_VIOLATIONS
+ measured = self.MANY_MEASURED
+ xml = self._coverage_xml(file_paths, violations, measured)
+
+ # Parse the reports
+ coverage = XmlCoverageReporter([xml], expand_coverage_report=True)
+
+ # Expect that the name is set
+ assert coverage.name() == "XML"
+
+ # By construction, each file has the same set
+ # of covered/uncovered lines
+ assert self.MANY_VIOLATIONS_EXPANDED_MANY_MEASURED == coverage.violations(
+ "file1.java"
+ )
+
+ def test_expand_unreported_lines_without_violations(self):
+ # Construct the XML report
+ file_paths = ["file1.java"]
+ # fixture
+ violations = {}
+ measured = self.MANY_MEASURED
+ xml = self._coverage_xml(file_paths, violations, measured)
+
+ # Parse the reports
+ coverage = XmlCoverageReporter([xml], expand_coverage_report=True)
+
+ assert set() == coverage.violations("file1.java")
+
+ def test_expand_unreported_lines_without_measured(self):
+ # Construct the XML report
+ file_paths = ["file1.java"]
+ # fixture
+ violations = {}
+ measured = {}
+ xml = self._coverage_xml(file_paths, violations, measured)
+
+ # Parse the reports
+ coverage = XmlCoverageReporter([xml], expand_coverage_report=True)
+
+ assert set() == coverage.violations("file1.java")
+
  def _coverage_xml(self, file_paths, violations, measured, source_paths=None):
  """
  Build an XML tree with source files specified by `file_paths`.