.gitattributes: define macro attribute binaryd for binary diff

.gitattributes

@@ -13,6 +13,13 @@
 #   - Avoid merge-conflict when merging from .gitattributeless branch to
 #     .gitattributed branch
 
+# This is the default "binary" macro attribute, but with diffing allowed.
+# Use when file contains diffable text, but isn't actually plaintext and thus
+# shouldn't have EOL conversion done.
+[attr]binaryd diff -merge -text
+# Example:
+#*.db	binaryd
+
 # Built-in diff patterns (disabled by default). The attribute `diff` implies
 # `text` and the above attributes are inherited.
 # https://www.git-scm.com/docs/gitattributes#_defining_a_custom_hunk_header

.pre-commit-config.yaml

@@ -13,6 +13,7 @@ default_language_version:
   python: pypy3
 
 repos:
+  # The repo from `pre-commit sample-config`
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v4.5.0
     hooks:
@@ -27,10 +28,15 @@ repos:
         exclude: .*\.nginx$
       - id: fix-byte-order-marker
       - id: trailing-whitespace
+        # Markdown allows double trailing space for forced line change. The
+        # hook appears to remove single ones.
+        args: ["--markdown-linebreak-ext", "md,markdown"]
         # Let's not touch LICENSE files or reuse.software directory
         exclude: ^LICENSES\/.*|LICENSE$
-        # File types depending on trailing whitespace. Use identify-cli
+        # Other file extensions where trailing whitespace may be intentional
-        exclude_types: [svg, markdown, tsv]
+        # and lack of it break things. Use identify-cli for figuring out more
+        # types to add.
+        exclude_types: [svg, tsv]
       #- id: check-docstring-first
       #- id: check-json
       - id: check-merge-conflict
@@ -44,6 +50,8 @@ repos:
           [--fix=auto]
           #- id: pretty-format-json
           #- id: requirements-txt-fixer
+
+  # Checks the ci: section on top of the file
   - repo: https://github.com/pre-commit-ci/pre-commit-ci-config
     rev: v1.6.1
     hooks:
@@ -62,18 +70,22 @@ repos:
   #   rev: "v1.3.0"
   #   hooks:
   #     - id: mypy
+
   # - repo: https://github.com/asottile/pyupgrade
   #   rev: v3.15.0
   #   hooks:
   #     - id: pyupgrade
+
   # - repo: https://github.com/asottile/reorder-python-imports
   #   rev: v3.12.0
   #   hooks:
   #     - id: reorder-python-imports
+
   # - repo: https://github.com/asottile/add-trailing-comma
   #   rev: v3.1.0
   #   hooks:
   #     - id: add-trailing-comma
+
   # GitHub Actions etc. configuration validity checking
   - repo: https://github.com/python-jsonschema/check-jsonschema
     rev: 0.27.0
@@ -103,6 +115,7 @@ repos:
     rev: "v3.0.3"
     hooks:
       - id: prettier
+        # These are handled by Black below
         exclude_types:
           [python, pyi, jupyter]
           #additional_dependencies: