Merge branch 'master' into always_compare

Author: Cadair

MANIFEST.in

@@ -3,5 +3,5 @@ include README.rst
 include CHANGES.md
 include tox.ini
 
-recursive-include tests *.py *.png
+recursive-include tests *.py *.json *.png
 recursive-include images *.png

pytest_mpl/plugin.py

@@ -481,12 +481,13 @@ def compare_image_to_hash_library(self, item, fig, result_dir):
 
         hash_library = self.load_hash_library(hash_library_filename)
         hash_name = self.generate_test_name(item)
+        
+        test_hash = self.generate_image_hash(item, fig)
 
         if hash_name not in hash_library:
             new_test = True
-            error_message = f"Hash for test '{hash_name}' not found in {hash_library_filename}."
-
-        test_hash = self.generate_image_hash(item, fig)
+            error_message = (f"Hash for test '{hash_name}' not found in {hash_library_filename}. "
+                             f"Generated hash is {test_hash}.")
 
         # Save the figure for later summary (will be removed later if not needed)
         test_image = (result_dir / "result.png").absolute()