Drop is_leaf property

Author: kpwtxt

README.md

@@ -171,8 +171,7 @@ mode (RFC 6902 JSON Patch over NDJSON).
 
 Each event carries the raw op (`event.op`) and an independent deep copy of the
 document so far (`event.snapshot`). For the common case of reacting to one
-field at a time, use the demux properties: `event.is_leaf` skips structural
-ops (root seed, empty-container init), `event.field` is the JSON Pointer with
+field at a time, use the demux properties: `event.field` is the JSON Pointer with
 the leading `/` stripped (`"intent"`, `"steps/0"`, `"address/city"`), and
 `event.value` is the op's value.
 
@@ -200,8 +199,6 @@ async def main() -> None:
         input="I was charged twice this month, please refund the duplicate.",
     )
     async for event in stream:
-        if not event.is_leaf:
-            continue
         match event.field:
             case "intent":
                 print(f"dispatching to {event.value} queue")

docs/client.md

@@ -232,11 +232,9 @@ Each `PatchEvent` carries:
   folds one into a object in place, returning the (possibly new) root.
 - `event.snapshot` — an independent deep copy of the JSON object built up to
   and including this op
-- `event.is_leaf` / `event.field` / `event.value` convenience demux for
-  the common case of reacting to one field at a time. `is_leaf` is `True`
-  for non-structural adds (skipping the root seed and empty-container init
-  ops); `field` is the JSON Pointer with the leading `/` stripped
-  (`"intent"`, `"steps/0"`, `"address/city"`).
+- `event.field` / `event.value` — `field` is the JSON Pointer with the leading `/` stripped
+  (`"intent"`, `"steps/0"`, `"address/city"`). `value` contains the current field content,
+  including empty lists `[]` or dictionary `{}` values.
 
 ```python
 import asyncio
@@ -258,8 +256,6 @@ async def main():
         input="I was charged twice this month, please refund the duplicate.",
     )
     async for event in stream:
-        if not event.is_leaf:
-            continue
         match event.field:
             case "intent":
                 asyncio.create_task(dispatch_to_queue(event.value))

examples/stream_fanout.py

@@ -76,7 +76,7 @@ async def main() -> None:
             max_tokens=400,
         )
         async for event in stream:
-            if not event.is_leaf:
+            if not event.value:
                 continue
             elapsed_ms = int((time.monotonic() - started) * 1000)
             if event.field.startswith("steps/"):

examples/stream_field_printer.py

@@ -34,7 +34,7 @@ async def main() -> None:
             input="Generate a profile for a senior backend engineer.",
         )
         async for event in stream:
-            if not event.is_leaf:
+            if not event.value:
                 continue
             print(f"{event.field:>24} = {event.value!r}")
     finally:

examples/stream_hitl_approval.py

@@ -74,8 +74,6 @@ async def main() -> None:
             max_tokens=300,
         )
         async for event in stream:
-            if not event.is_leaf:
-                continue
             match event.field:
                 case "action":
                     proposed_action = event.value

src/dottxt/streaming.py

@@ -37,27 +37,13 @@ class PatchEvent:
     is an independent deep copy, so callers may stash events without later
     ops mutating earlier snapshots.
 
-    The ``is_leaf`` / ``field`` / ``value`` properties demux the op for the
+    The ``field`` / ``value`` properties demux the op for the
     common pattern of reacting to one structured-output field at a time.
     """
 
     op: dict[str, Any]
     snapshot: dict[str, Any] | list[Any]
 
-    @property
-    def is_leaf(self) -> bool:
-        """True iff this op contributes a single leaf value.
-
-        False for the root seed (``path == ""``), for empty-container init
-        ops (``value`` is ``{}`` or ``[]``), and for any op that is not an
-        ``add``.
-        """
-        return (
-            self.op.get("op") == "add"
-            and self.op.get("path", "") != ""
-            and self.op.get("value") not in ({}, [])
-        )
-
     @property
     def field(self) -> str:
         """JSON Pointer for this op with the leading ``/`` stripped.

tests/test_streaming.py

@@ -11,36 +11,6 @@
 from dottxt.streaming import PatchEvent, PatchStreamError, apply_add, stream
 
 
-def test_patch_event_is_leaf_for_top_level_leaf() -> None:
-    """A non-empty add at a non-root path is a leaf."""
-    event = PatchEvent(
-        op={"op": "add", "path": "/intent", "value": "billing"},
-        snapshot={"intent": "billing"},
-    )
-    assert event.is_leaf is True
-    assert event.field == "intent"
-    assert event.value == "billing"
-
-
-def test_patch_event_is_leaf_false_for_root_seed() -> None:
-    """The root seed op is structural, not a leaf."""
-    event = PatchEvent(op={"op": "add", "path": "", "value": {}}, snapshot={})
-    assert event.is_leaf is False
-    assert event.field == ""
-
-
-def test_patch_event_is_leaf_false_for_empty_container() -> None:
-    """Empty-object and empty-array seed ops are structural."""
-    obj_seed = PatchEvent(
-        op={"op": "add", "path": "/address", "value": {}}, snapshot={"address": {}}
-    )
-    arr_seed = PatchEvent(
-        op={"op": "add", "path": "/steps", "value": []}, snapshot={"steps": []}
-    )
-    assert obj_seed.is_leaf is False
-    assert arr_seed.is_leaf is False
-
-
 def test_patch_event_field_for_array_index_and_nested_path() -> None:
     """Array indices and nested object paths keep their joined segments."""
     arr = PatchEvent(
@@ -55,15 +25,6 @@ def test_patch_event_field_for_array_index_and_nested_path() -> None:
     assert nested.field == "address/city"
 
 
-def test_patch_event_is_leaf_handles_falsy_primitives() -> None:
-    """Falsy primitives (0, "", False) are still leaves, only {} / [] are structural."""
-    for value in (0, "", False, None):
-        event = PatchEvent(
-            op={"op": "add", "path": "/x", "value": value}, snapshot={"x": value}
-        )
-        assert event.is_leaf is True, value
-
-
 def test_apply_add_replaces_root_for_empty_path() -> None:
     """An op with ``path == ""`` replaces the document root."""
     assert apply_add(None, "", {}) == {}