refactor: specialize exceptionsnedbat/exceptions

CoverageException is fine as a base class, but not good to use for
raising (and catching sometimes).  Introduce specialized exceptions that
allow third-party tools to integrate better.

1 files changed, 2 insertions, 2 deletions

diff --git a/coverage/html.py b/coverage/html.py
index 2acc8aba..ae1d041f 100644
--- a/coverage/html.py
+++ b/coverage/html.py
@@ -12,7 +12,7 @@ import types
 
 import coverage
 from coverage.data import add_data_to_hash
-from coverage.exceptions import CoverageException
+from coverage.exceptions import NoDataError
 from coverage.files import flat_rootname
 from coverage.misc import ensure_dir, file_be_gone, Hasher, isolate_module, format_local_datetime
 from coverage.misc import human_sorted, plural
@@ -208,7 +208,7 @@ class HtmlReporter:
             self.html_file(fr, analysis)
 
         if not self.all_files_nums:
-            raise CoverageException("No data to report.")
+            raise NoDataError("No data to report.")
 
         self.totals = sum(self.all_files_nums)