From 29d788bb94d7f954e6a328f3ba4a84e04ca8aea0 Mon Sep 17 00:00:00 2001
From: Robsdedude <rouven.bauer@neo4j.com>
Date: Thu, 24 Jul 2025 16:24:30 +0200
Subject: [PATCH] Vector types: optimize error path

The pure-python implementations of `Vector.from_native` perform type checks.
This patch makes the driver fail fast when passing incompatible types instead
of scanning the whole Iterable parameter.
---
 src/neo4j/vector.py | 30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/src/neo4j/vector.py b/src/neo4j/vector.py
index ca01ad76..6a20d5cf 100644
--- a/src/neo4j/vector.py
+++ b/src/neo4j/vector.py
@@ -753,10 +753,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_float = tuple(item for item in data if not isinstance(item, float))
+        non_float_gen = (item for item in data if not isinstance(item, float))
+        non_float = next(non_float_gen, None)
         if non_float:
             raise TypeError(
-                f"Cannot build f64 vector from {type(non_float[0]).__name__}, "
+                f"Cannot build f64 vector from {type(non_float).__name__}, "
                 "expected float."
             )
         return cls(_np.fromiter(data, dtype=_np.dtype(">f8")).tobytes())
@@ -826,10 +827,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_float = tuple(item for item in data if not isinstance(item, float))
+        non_float_gen = (item for item in data if not isinstance(item, float))
+        non_float = next(non_float_gen, None)
         if non_float:
             raise TypeError(
-                f"Cannot build f32 vector from {type(non_float[0]).__name__}, "
+                f"Cannot build f32 vector from {type(non_float).__name__}, "
                 "expected float."
             )
         return cls(_np.fromiter(data, dtype=_np.dtype(">f4")).tobytes())
@@ -903,10 +905,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_int = tuple(item for item in data if not isinstance(item, int))
+        non_int_gen = (item for item in data if not isinstance(item, int))
+        non_int = next(non_int_gen, None)
         if non_int:
             raise TypeError(
-                f"Cannot build i64 vector from {type(non_int[0]).__name__}, "
+                f"Cannot build i64 vector from {type(non_int).__name__}, "
                 "expected int."
             )
         data = _t.cast(tuple[int, ...], data)
@@ -994,10 +997,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_int = tuple(item for item in data if not isinstance(item, int))
+        non_int_gen = (item for item in data if not isinstance(item, int))
+        non_int = next(non_int_gen, None)
         if non_int:
             raise TypeError(
-                f"Cannot build i32 vector from {type(non_int[0]).__name__}, "
+                f"Cannot build i32 vector from {type(non_int).__name__}, "
                 "expected int."
             )
         data = _t.cast(tuple[int, ...], data)
@@ -1085,10 +1089,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_int = tuple(item for item in data if not isinstance(item, int))
+        non_int_gen = (item for item in data if not isinstance(item, int))
+        non_int = next(non_int_gen, None)
         if non_int:
             raise TypeError(
-                f"Cannot build i16 vector from {type(non_int[0]).__name__}, "
+                f"Cannot build i16 vector from {type(non_int).__name__}, "
                 "expected int."
             )
         data = _t.cast(tuple[int, ...], data)
@@ -1176,10 +1181,11 @@ def _from_native_rust(cls, data: _t.Iterable[object], /) -> _t.Self:
     @classmethod
     def _from_native_np(cls, data: _t.Iterable[object], /) -> _t.Self:
         data = tuple(data)
-        non_int = tuple(item for item in data if not isinstance(item, int))
+        non_int_gen = (item for item in data if not isinstance(item, int))
+        non_int = next(non_int_gen, None)
         if non_int:
             raise TypeError(
-                f"Cannot build i8 vector from {type(non_int[0]).__name__}, "
+                f"Cannot build i8 vector from {type(non_int).__name__}, "
                 "expected int."
             )
         data = _t.cast(tuple[int, ...], data)