html total must account for files 100% covered #549issue-549

The --skip-covered implementation for html must not just skip the
files that are 100% covered. It must remember them and not fail with a
"no coverage data" when all files are 100% covered.

The statistics about the files that are 100% covered must also be
summed in the total for the index.html page.

close #549

2 files changed, 14 insertions, 3 deletions

diff --git a/coverage/html.py b/coverage/html.py
index 22783ef..4a8c5a5 100644
--- a/coverage/html.py
+++ b/coverage/html.py
@@ -105,6 +105,7 @@ class HtmlReporter(Reporter):
         self.coverage = cov
 
         self.files = []
+        self.files_skip_covered = []
         self.has_arcs = self.coverage.data.has_arcs()
         self.status = HtmlStatus()
         self.extra_css = None
@@ -137,7 +138,7 @@ class HtmlReporter(Reporter):
         # Process all the files.
         self.report_files(self.html_file, morfs, self.config.html_dir)
 
-        if not self.files:
+        if not self.files and not self.files_skip_covered:
             raise CoverageException("No data to report.")
 
         # Write the index file.
@@ -178,6 +179,7 @@ class HtmlReporter(Reporter):
             no_missing_lines = (nums.n_missing == 0)
             no_missing_branches = (nums.n_partial_branches == 0)
             if no_missing_lines and no_missing_branches:
+                self.files_skip_covered.append(nums)
                 return
 
         source = fr.source()
@@ -292,7 +294,7 @@ class HtmlReporter(Reporter):
         """Write the index.html file for this report."""
         index_tmpl = Templite(read_data("index.html"), self.template_globals)
 
-        self.totals = sum(f['nums'] for f in self.files)
+        self.totals = sum([f['nums'] for f in self.files] + self.files_skip_covered)
 
         html = index_tmpl.render({
             'has_arcs': self.has_arcs,
diff --git a/tests/test_html.py b/tests/test_html.py
index 1c9fa43..06d5946 100644
--- a/tests/test_html.py
+++ b/tests/test_html.py
@@ -47,7 +47,7 @@ class HtmlTestHelpers(CoverageTest):
         self.clean_local_file_imports()
         cov = coverage.Coverage(**(covargs or {}))
         self.start_import_stop(cov, "main_file")
-        cov.html_report(**(htmlargs or {}))
+        return cov.html_report(**(htmlargs or {}))
 
     def remove_html_files(self):
         """Remove the HTML files created as part of the HTML report."""
@@ -464,6 +464,15 @@ class HtmlTest(HtmlTestHelpers, CoverageTest):
         self.assert_doesnt_exist("htmlcov/main_file_py.html")
         self.assert_exists("htmlcov/not_covered_py.html")
 
+    def test_report_skip_covered_100(self):
+        self.make_file("main_file.py", """
+            def normal():
+                print("z")
+            normal()
+        """)
+        assert self.run_coverage(covargs=dict(source="."), htmlargs=dict(skip_covered=True)) == 100.0
+        self.assert_doesnt_exist("htmlcov/main_file_py.html")
+
     def test_report_skip_covered_branches(self):
         self.make_file("main_file.py", """
             import not_covered