Implement 'repr' for 'auto' datafiles

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## 1.4 (beta)
 
 - Added support for accessing `Dict` keys as attributes.
+- Added a proper `repr()` implementation for `auto()` datafiles.
 
 ## 1.3 (2022-04-09)
 

datafiles/decorators.py

@@ -45,7 +45,13 @@ def auto(filename: str, **kwargs):
     kwargs["infer"] = True
 
     path = Path.cwd() / filename
+    name = path.stem.strip(".").capitalize()
 
-    cls = type(path.stem.strip("."), (), {})
+    def auto_repr(self):
+        items = (f"{k}={v!r}" for k, v in self.__dict__.items() if k != "datafile")
+        params = ", ".join(items)
+        return f"{name}({params})"
+
+    cls = type(name, (), {"__repr__": auto_repr})
 
     return datafile(str(path), **kwargs)(cls)()

notebooks/profile_default/startup/samples.py

@@ -0,0 +1,17 @@
+from datafiles import datafile, auto, Missing
+
+
+@datafile("./notebooks/files/items/{self.name}.yml")
+class InventoryItem:
+    """Class for keeping track of an item in inventory."""
+
+    name: str
+    unit_price: float
+    quantity_on_hand: int = 0
+
+    def total_cost(self) -> float:
+        return self.unit_price * self.quantity_on_hand
+
+
+item = InventoryItem("foobar", Missing)
+sample = auto("./notebooks/files/sample.yml")

pyproject.toml

@@ -1,7 +1,7 @@
 [tool.poetry]
 
 name = "datafiles"
-version = "1.4b1"
+version = "1.4b2"
 description = "File-based ORM for dataclasses."
 
 license = "MIT"
@@ -44,8 +44,8 @@ classifiers = [
 python = "^3.7"
 
 # Formats
-"ruamel.yaml" = "^0.17.20"
-tomlkit = "^0.7.2"
+"ruamel.yaml" = "^0.17.21"
+tomlkit = "^0.10.1"
 
 # ORM
 parse = "^1.12"

tests/test_file_inference.py

@@ -7,6 +7,22 @@
 
 
 def describe_auto():
+    def it_implements_repr(expect):
+        write(
+            "tmp/sample.yml",
+            """
+            items:
+              - 1
+              - 2
+            value: abc
+            """,
+        )
+
+        logbreak("Inferring object")
+        sample = auto("tmp/sample.yml")
+
+        expect(repr(sample)) == "Sample(items=[1, 2], value='abc')"
+
     @pytest.mark.parametrize(
         ("filename", "count"),
         [