From 393e0b4339ca843b0bf2c77d77104b23f19efbc1 Mon Sep 17 00:00:00 2001
From: Danijar Hafner <mail@danijar.com>
Date: Sun, 11 Aug 2019 11:27:32 -0400
Subject: [PATCH] Add no new logging handlers when reloading the module.

User @epogrebnyak found the bug. Fixes #11. Closes #27.
---
 handout/__init__.py           | 7 ++++---
 handout/handout.py            | 3 +++
 handout/tests/__init__.py     | 0
 handout/tests/test_handout.py | 6 ++++--
 4 files changed, 11 insertions(+), 5 deletions(-)
 delete mode 100644 handout/tests/__init__.py

diff --git a/handout/__init__.py b/handout/__init__.py
index de017c7..3b1aa59 100644
--- a/handout/__init__.py
+++ b/handout/__init__.py
@@ -8,6 +8,7 @@
 logger = logging.getLogger('handout')
 logger.setLevel(logging.INFO)
 logger.propagate = False  # Global logger should not print messages again.
-handler = logging.StreamHandler(sys.stdout)
-handler.setFormatter(logging.Formatter('%(message)s'))
-logger.addHandler(handler)
+if not logger.handlers:  # Reloading the module should not add another handler.
+  handler = logging.StreamHandler(sys.stdout)
+  handler.setFormatter(logging.Formatter('%(message)s'))
+  logger.addHandler(handler)
diff --git a/handout/handout.py b/handout/handout.py
index 4f9b087..b27dad0 100644
--- a/handout/handout.py
+++ b/handout/handout.py
@@ -16,6 +16,9 @@ def __init__(self, directory, title='Handout'):
     self._title = title
     self._blocks = collections.defaultdict(list)
     self._pending = []
+    # The logger is configured in handout/__init__.py to make it available
+    # right after importing the handout package. This allows the user to change
+    # the logging level, message format, etc.
     self._logger = logging.getLogger('handout')
     for info in inspect.stack():
       if info.filename == __file__:
diff --git a/handout/tests/__init__.py b/handout/tests/__init__.py
deleted file mode 100644
index e69de29..0000000
diff --git a/handout/tests/test_handout.py b/handout/tests/test_handout.py
index 95f143f..2fc6a2e 100644
--- a/handout/tests/test_handout.py
+++ b/handout/tests/test_handout.py
@@ -1,5 +1,7 @@
 import handout
 
+
 def test_handout_on_title_arg_inserts_title(tmp_path):
-    output = handout.Handout(directory=tmp_path, title='This string')._generate(source='')   
-    assert '<title>This string</title>' in output
\ No newline at end of file
+    doc = handout.Handout(directory=tmp_path, title='This string')
+    output = doc._generate(source='')
+    assert '<title>This string</title>' in output