Bring test coverage of src/dags to 100% (#76)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: hmgaudecker

.github/workflows/main.yml

@@ -57,7 +57,7 @@ jobs:
       - uses: actions/checkout@v6
       - uses: prefix-dev/setup-pixi@v0.9.4
         with:
-          pixi-version: v0.64.0
+          pixi-version: v0.65.0
           cache: true
           cache-write: ${{ github.event_name == 'push' && github.ref_name == 'main' }}
           frozen: true

CHANGES.md

@@ -6,13 +6,15 @@ releases are available on [conda-forge](https://anaconda.org/conda-forge/dags).
 
 ## 0.5.0
 
+- :gh:`76` Add a couple of tests to bring coverage to 100% (:ghuser:`hmgaudecker`).
+
 - :gh:`75` Streamline public API (:ghuser:`hmgaudecker`).
 
   - Deprecate `one_function_without_tree_logic`,
     `functions_without_tree_logic`, and `fail_if_paths_are_invalid`
     in favor of `get_one_function_without_tree_logic`,
-    `get_functions_without_tree_logic`, and
-    `dags.tree.validation.fail_if_paths_are_invalid`.
+    `get_functions_without_tree_logic`
+  - Deprecate `dags.tree.fail_if_paths_are_invalid` (call from `dags.tree.validation`)
 
 - :gh:`65` Update docs and use Jupyter Book for documentation (:ghuser:`hmgaudecker`).
 

tests/test_dag.py

@@ -513,3 +513,66 @@ def f2():
 
     assert aggregated() is False
     assert "return" not in inspect.get_annotations(aggregated)
+
+
+def test_concatenate_functions_invalid_return_type_raises() -> None:
+    with pytest.raises(DagsError, match="Invalid return type"):
+        concatenate_functions(
+            functions=[_leisure, _consumption],
+            targets=["_leisure", "_consumption"],
+            return_type="set",  # type: ignore[arg-type]
+        )
+
+
+def test_get_ancestors_include_targets() -> None:
+    calculated = get_ancestors(
+        functions=[_utility, _unrelated, _leisure, _consumption],
+        targets="_utility",
+        include_targets=True,
+    )
+    expected = {
+        "_utility",
+        "_consumption",
+        "_leisure",
+        "working_hours",
+        "wage",
+        "leisure_weight",
+    }
+    assert calculated == expected
+
+
+def test_concatenate_functions_non_string_targets() -> None:
+    with pytest.raises(DagsError, match="Targets must be strings"):
+        concatenate_functions(
+            functions={"f": lambda: 1},
+            targets=[1],  # type: ignore[list-item]
+        )
+
+
+def test_aggregator_exception_in_get_annotations() -> None:
+    """Test that an aggregator whose annotations cause an exception is handled."""
+
+    def f1() -> int:
+        return 1
+
+    def f2() -> int:
+        return 2
+
+    # Create an object that is callable but raises on get_annotations
+    class BadAggregator:
+        def __call__(self, a: int, b: int) -> int:
+            return a + b
+
+        @property
+        def __annotations__(self) -> dict[str, Any]:
+            msg = "bad annotations"
+            raise TypeError(msg)
+
+    aggregator = BadAggregator()
+    result = concatenate_functions(
+        functions={"f1": f1, "f2": f2},
+        targets=["f1", "f2"],
+        aggregator=aggregator,
+        set_annotations=True,
+    )
+    assert result() == 3

tests/test_dag_tree/test_dag_tree.py

@@ -5,6 +5,7 @@
 import pytest
 
 from dags.tree import concatenate_functions_tree
+from dags.tree.dag_tree import create_dag_tree
 from dags.tree.typing import (
     NestedFunctionDict,
     NestedInputDict,
@@ -176,3 +177,16 @@ def f(a, b):
         enforce_signature=True,
     )
     assert concatenated_func({"a": 1}) == {"f": 2}
+
+
+def test_create_dag_tree(functions_simple: NestedFunctionDict) -> None:
+    inputs: NestedInputDict = {
+        "n1": {"a": 1, "b": 2},
+        "n2": {"a": 3, "b": {"g": 4}},
+    }
+    targets: NestedTargetDict = {"n1": {"f": None}}
+
+    dag = create_dag_tree(functions=functions_simple, inputs=inputs, targets=targets)
+
+    assert "n1__f" in dag.nodes
+    assert "n1__g" in dag.nodes

tests/test_process_output.py

@@ -4,6 +4,7 @@
 
 import pytest
 
+from dags.exceptions import DagsError
 from dags.output import (
     aggregated_output,
     dict_output,
@@ -88,3 +89,29 @@ def f():
         return (1, 2)
 
     assert f() == [1, 2]
+
+
+def test_dict_output_keys_none() -> None:
+    with pytest.raises(DagsError, match="'keys' parameter is required"):
+        dict_output(keys=None)  # ty: ignore[invalid-argument-type]
+
+
+def test_aggregated_output_aggregator_none() -> None:
+    with pytest.raises(DagsError, match="'aggregator' parameter is required"):
+        aggregated_output(aggregator=None)  # ty: ignore[invalid-argument-type]
+
+
+def test_aggregated_output_direct_call() -> None:
+    def f():
+        return (10, 20)
+
+    g = aggregated_output(f, aggregator=lambda x, y: x + y)
+    assert g() == 30
+
+
+def test_aggregated_output_decorator_usage() -> None:
+    @aggregated_output(aggregator=lambda x, y: x + y)
+    def f():
+        return (10, 20)
+
+    assert f() == 30

tests/test_signature.py

@@ -237,3 +237,11 @@ def test_with_signature_invalid_args_type() -> None:
         @with_signature(args="invalid")
         def f(*args, **kwargs):
             pass
+
+
+def test_with_signature_invalid_args_type_int() -> None:
+    with pytest.raises(DagsError, match="Invalid type for arg"):
+
+        @with_signature(args=42)  # type: ignore[arg-type]
+        def f(*args, **kwargs):
+            pass