Merge remote-tracking branch 'origin/main' into reproduce-441

bibtexparser/middlewares/__init__.py

@@ -7,6 +7,7 @@
     LatexDecodingMiddleware,
     LatexEncodingMiddleware,
 )
+from bibtexparser.middlewares.middleware import BlockMiddleware, LibraryMiddleware
 from bibtexparser.middlewares.month import (
     MonthAbbreviationMiddleware,
     MonthIntMiddleware,

bibtexparser/model.py

@@ -304,6 +304,16 @@ def set_field(self, field: Field):
         else:
             self._fields.append(field)
 
+    def pop_field(self, key: str) -> Optional[Field]:
+        """Removes and returns the field with the given key, if present."""
+        try:
+            field = self.fields_dict.pop(key)
+        except KeyError:
+            return None
+
+        self._fields = [f for f in self._fields if f.key != key]
+        return field
+
     def __getitem__(self, key: str) -> Any:
         """Dict-mimicking index.
 
@@ -326,6 +336,14 @@ def __setitem__(self, key: str, value: Any):
         """
         self.set_field(Field(key, value))
 
+    def __delitem__(self, key):
+        """Dict-mimicking index.
+
+        This serves for partial v1.x backwards compatibility,
+        as well as for a shorthand for `pop_field`.
+        """
+        self.pop_field(key)
+
     def items(self):
         """Dict-mimicking, for partial v1.x backwards compatibility.
 

docs/source/customize.rst

@@ -113,7 +113,7 @@ and share them with the community.
 We will be happy to provide a list of community-provided middleware layers here, so please let us know if you have written one!
 
 .. note::
-    To write your own middleware, simply extend the :class:`bibtexparser.middlewares.Blockmiddleware`
+    To write your own middleware, simply extend the :class:`bibtexparser.middlewares.BlockMiddleware`
     (for functions working on blocks individually, such as encoding) or :class:`bibtexparser.middlewares.LibraryMiddleware`
     (for library-wide transformations, such as sorting blocks) and implement the superclass methods
     according to the python docstrings. Make sure to check out some core middleware layers for examples.

tests/middleware_tests/test_custom_middleware_smoke.py

@@ -0,0 +1,33 @@
+"""Smoke test for custom middleware, based on the #440 by @tdegeus"""
+
+import bibtexparser
+from bibtexparser.middlewares.middleware import BlockMiddleware
+
+bibtex_str = """
+@ARTICLE{Cesar2013,
+  author = {Jean César and T. W. J. de Geus},
+  title = {An amazing title},
+  year = {2013},
+  pages = {12--23},
+  volume = {12},
+  journal = {Nice Journal}
+}
+"""
+
+
+abbreviations = {"Nice Journal": "NJ", "Another Nice Journal": "ANJ"}
+
+
+class JournalAbbreviate(BlockMiddleware):
+    def transform_entry(self, entry, *args, **kwargs):
+        if entry["journal"] in abbreviations:
+            entry["journal"] = abbreviations[entry["journal"]]
+        return entry
+
+
+def test_custom_middleware_smoke():
+    """Test that the very simple custom middleware above works."""
+    library = bibtexparser.parse_string(
+        bibtex_str, append_middleware=[JournalAbbreviate(True)]
+    )
+    assert library.entries[0]["journal"] == "NJ"

tests/test_model.py

@@ -1,6 +1,8 @@
 from copy import copy, deepcopy
 from textwrap import dedent
 
+import pytest
+
 from bibtexparser.model import (
     Entry,
     ExplicitComment,
@@ -311,3 +313,9 @@ def test_entry_fields_shorthand():
     assert entry.fields_dict["myNewField"].key == "myNewField"
     assert entry.fields_dict["myNewField"].value == "new_value"
     assert entry.fields_dict["myNewField"].start_line is None
+
+    del entry["myNewField"]
+    assert "myNewField" not in entry.fields_dict
+    assert len([f for f in entry.fields if f.key == "myNewField"]) == 0
+    with pytest.raises(KeyError):
+        entry["myNewField"]