Merge pull request #198 from DanCardin/dc/propagate-context

fix: Ensure  args supply the correct parent context to the arg's action handler.

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## 0.26
 
+### 0.26.4
+- fix: Ensure `propagate=True` args supply the correct parent context to the arg's action handler.
+
 ### 0.26.3
 - fix: Reexport Empty/EmptyType types at the root.
 

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "cappa"
-version = "0.26.3"
+version = "0.26.4"
 description = "Declarative CLI argument parser."
 
 urls = { repository = "https://github.com/dancardin/cappa" }

src/cappa/parser.py

@@ -247,23 +247,24 @@ def propagated_context(self) -> dict[str, ParseContext]:
     def next_argument(self):
         return self.arguments.popleft()
 
+    def resolve_context(self, field_name: str, option: RawOption | None = None):
+        context = self
+        if option and field_name in self.propagated_options:
+            context = self.propagated_context[field_name]
+        return context
+
     def set_result(
         self,
         field_name: str,
         value: typing.Any,
         option: RawOption | None = None,
         has_value: bool = True,
     ):
-        context = self
-        if option:
-            if field_name in self.propagated_options:
-                context = self.propagated_context[field_name]
-
-            if field_name in context.missing_options:
-                context.missing_options.remove(field_name)
+        if option and field_name in self.missing_options:
+            self.missing_options.remove(field_name)
 
         if has_value:
-            context.result[field_name] = value
+            self.result[field_name] = value
 
     def push(self, command: Command, name: str) -> ParseContext:
         nested_context = ParseContext.from_command(command, parent_context=self)
@@ -639,10 +640,13 @@ def consume_arg(
 
     action_handler = determine_action_handler(arg.action)
 
+    # Propagated arguments need to supply the correct parent context to their action handler.
+    resolved_context = context.resolve_context(field_name, option)
+
     fulfilled_deps: dict = {
         Command: parse_state.current_command,
         Output: parse_state.output,
-        ParseContext: context,
+        ParseContext: resolved_context,
         ParseState: parse_state,
         Arg: arg,
         Value: Value(result),
@@ -654,7 +658,9 @@ def consume_arg(
     kwargs = fulfill_deps(action_handler, fulfilled_deps).kwargs
     result = action_handler(**kwargs)
 
-    context.set_result(field_name, result, option, assert_type(arg.has_value, bool))
+    resolved_context.set_result(
+        field_name, result, option, assert_type(arg.has_value, bool)
+    )
 
     check_deprecated(parse_state, arg, option)
 

tests/arg/test_propagate.py

@@ -6,6 +6,7 @@
 from typing_extensions import Annotated
 
 import cappa
+from cappa.subcommand import Subcommands
 from tests.utils import CapsysOutput, parse
 
 
@@ -133,3 +134,24 @@ class Command:
     assert "foo" in output.stdout
     assert "Everywhere" in output.stdout
     assert "Nowhere" not in output.stdout
+
+
+def test_count():
+    """Test that actions requiring accumulated prior state (e.g. count) **get** values from the correct context."""
+
+    @dataclass
+    class Command:
+        foo: Annotated[int, cappa.Arg(short=True, propagate=True, count=True)] = 1
+        subcommand: Subcommands[One | None] = None
+
+    result = parse(Command, "-f")
+    assert result == Command(1, None)
+
+    result = parse(Command, "-fff")
+    assert result == Command(3, None)
+
+    result = parse(Command, "one", "-f")
+    assert result == Command(1, One())
+
+    result = parse(Command, "one", "-fff")
+    assert result == Command(3, One())