1 files changed, 144 insertions, 0 deletions
diff --git a/tests/test_json.py b/tests/test_json.py
new file mode 100644
index 00000000..1ae5764e
--- /dev/null
+++ b/tests/test_json.py
@@ -0,0 +1,144 @@
+# coding: utf-8
+# Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0
+# For details: https://github.com/nedbat/coveragepy/blob/master/NOTICE.txt
+
+"""Test json-based summary reporting for coverage.py"""
+from datetime import datetime
+import json
+import os
+
+import coverage
+from tests.coveragetest import UsingModulesMixin, CoverageTest
+
+
+class JsonReportTest(UsingModulesMixin, CoverageTest):
+    """Tests of the JSON reports from coverage.py."""
+    def _assert_expected_json_report(self, cov, expected_result):
+        """
+        Helper for tests that handles the common ceremony so the tests can be clearly show the
+        consequences of setting various arguments.
+        """
+        self.make_file("a.py", """\
+            a = {'b': 1}
+            if a.get('a'):
+                b = 1
+            """)
+        a = self.start_import_stop(cov, "a")
+        output_path = os.path.join(self.temp_dir, "a.json")
+        cov.json_report(a, outfile=output_path)
+        with open(output_path) as result_file:
+            parsed_result = json.load(result_file)
+        self.assert_recent_datetime(
+            datetime.strptime(parsed_result['meta']['timestamp'], "%Y-%m-%dT%H:%M:%S.%f")
+        )
+        del (parsed_result['meta']['timestamp'])
+        assert parsed_result == expected_result
+
+    def test_branch_coverage(self):
+        cov = coverage.Coverage(branch=True)
+        expected_result = {
+            'meta': {
+                "version": coverage.__version__,
+                "branch_coverage": True,
+                "show_contexts": False,
+            },
+            'files': {
+                'a.py': {
+                    'executed_lines': [1, 2],
+                    'missing_lines': [3],
+                    'excluded_lines': [],
+                    'summary': {
+                        'missing_lines': 1,
+                        'covered_lines': 2,
+                        'num_statements': 3,
+                        'num_branches': 2,
+                        'excluded_lines': 0,
+                        'num_partial_branches': 1,
+                        'percent_covered': 60.0
+                    }
+                }
+            },
+            'totals': {
+                'missing_lines': 1,
+                'covered_lines': 2,
+                'num_statements': 3,
+                'num_branches': 2,
+                'excluded_lines': 0,
+                'num_partial_branches': 1,
+                'percent_covered': 60.0
+            }
+        }
+        self._assert_expected_json_report(cov, expected_result)
+
+    def test_simple_line_coverage(self):
+        cov = coverage.Coverage()
+        expected_result = {
+            'meta': {
+                "version": coverage.__version__,
+                "branch_coverage": False,
+                "show_contexts": False,
+            },
+            'files': {
+                'a.py': {
+                    'executed_lines': [1, 2],
+                    'missing_lines': [3],
+                    'excluded_lines': [],
+                    'summary': {
+                        'excluded_lines': 0,
+                        'missing_lines': 1,
+                        'covered_lines': 2,
+                        'num_statements': 3,
+                        'percent_covered': 66.66666666666667
+                    }
+                }
+            },
+            'totals': {
+                'excluded_lines': 0,
+                'missing_lines': 1,
+                'covered_lines': 2,
+                'num_statements': 3,
+                'percent_covered': 66.66666666666667
+            }
+        }
+        self._assert_expected_json_report(cov, expected_result)
+
+    def test_context(self):
+        cov = coverage.Coverage(context="cool_test")
+        cov.config.json_show_contexts = True
+        expected_result = {
+            'meta': {
+                "version": coverage.__version__,
+                "branch_coverage": False,
+                "show_contexts": True,
+            },
+            'files': {
+                'a.py': {
+                    'executed_lines': [1, 2],
+                    'missing_lines': [3],
+                    'excluded_lines': [],
+                    "contexts": {
+                        "1": [
+                            "cool_test"
+                        ],
+                        "2": [
+                            "cool_test"
+                        ]
+                    },
+                    'summary': {
+                        'excluded_lines': 0,
+                        'missing_lines': 1,
+                        'covered_lines': 2,
+                        'num_statements': 3,
+                        'percent_covered': 66.66666666666667
+                    }
+                }
+            },
+            'totals': {
+                'excluded_lines': 0,
+                'missing_lines': 1,
+                'covered_lines': 2,
+                'num_statements': 3,
+                'percent_covered': 66.66666666666667
+            }
+        }
+        self._assert_expected_json_report(cov, expected_result)