fix: raise chained errors with "from" #998

This makes exceptions report their causes correctly, as "The above exception was
the direct cause of the following exception" instead of "During handling of the
above exception, another exception occurred."

1 files changed, 2 insertions, 2 deletions

diff --git a/coverage/templite.py b/coverage/templite.py
index 2ceeb6e2..ab3cf1cf 100644
--- a/coverage/templite.py
+++ b/coverage/templite.py
@@ -288,10 +288,10 @@ class Templite:
             except AttributeError:
                 try:
                     value = value[dot]
-                except (TypeError, KeyError):
+                except (TypeError, KeyError) as exc:
                     raise TempliteValueError(
                         f"Couldn't evaluate {value!r}.{dot}"
-                    )
+                    ) from exc
             if callable(value):
                 value = value()
         return value