(arrow-go) branch main updated: fix(array): avoid allocating for ReserveData(0) (#895)

[zeroshade]

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zeroshade pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/arrow-go.git


The following commit(s) were added to refs/heads/main by this push:
     new 8a09b917 fix(array): avoid allocating for ReserveData(0) (#895)
8a09b917 is described below

commit 8a09b917bcb4f76153259c1ce0ef39a947f4aaf3
Author: Minh Vu <vuhoangmin...@gmail.com>
AuthorDate: Sat Jul 18 18:54:56 2026 +0200

    fix(array): avoid allocating for ReserveData(0) (#895)
    
    BinaryViewBuilder.ReserveData always delegated to the block builder, so 
ReserveData(0) created a full default data block even when every value remained 
inline. Return early on zero-length reservations so no unused variadic data 
buffer is allocated; positive reservations and the public API are unchanged. 
Integration JSON expectations are updated accordingly.
---
 arrow/array/binary_test.go             |  7 +++++++
 arrow/array/binarybuilder.go           |  3 +++
 arrow/internal/arrjson/arrjson_test.go | 12 ++++--------
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/arrow/array/binary_test.go b/arrow/array/binary_test.go
index 0e27b9bb..8e91860d 100644
--- a/arrow/array/binary_test.go
+++ b/arrow/array/binary_test.go
@@ -732,6 +732,13 @@ func TestBinaryViewBuilderRejectsOversizedValues(t 
*testing.T) {
        })
 }
 
+func TestBinaryViewBuilderReserveData0DoesNotAllocate(t *testing.T) {
+       b := NewBinaryViewBuilder(binaryViewNoAllocAllocator{})
+       defer b.Release()
+
+       b.ReserveData(0)
+}
+
 func TestBinaryViewStringRoundTrip(t *testing.T) {
        mem := memory.NewCheckedAllocator(memory.DefaultAllocator)
        defer mem.AssertSize(t, 0)
diff --git a/arrow/array/binarybuilder.go b/arrow/array/binarybuilder.go
index 698e7c53..07114df9 100644
--- a/arrow/array/binarybuilder.go
+++ b/arrow/array/binarybuilder.go
@@ -476,6 +476,9 @@ func checkBinaryViewValueSize(length int64) {
 
 func (b *BinaryViewBuilder) ReserveData(length int) {
        checkBinaryViewValueSize(int64(length))
+       if length == 0 {
+               return
+       }
        b.blockBuilder.Reserve(int(length))
 }
 
diff --git a/arrow/internal/arrjson/arrjson_test.go 
b/arrow/internal/arrjson/arrjson_test.go
index 7e2f386f..232270b9 100644
--- a/arrow/internal/arrjson/arrjson_test.go
+++ b/arrow/internal/arrjson/arrjson_test.go
@@ -6186,8 +6186,7 @@ func makeViewTypesWantJSONs() string {
               "SIZE": 1,
               "INLINED": "35"
             }
-          ],
-          "VARIADIC_DATA_BUFFERS": [""]
+          ]
         },
         {
           "name": "string_view",
@@ -6220,8 +6219,7 @@ func makeViewTypesWantJSONs() string {
               "SIZE": 1,
               "INLINED": "5"
             }
-          ],
-          "VARIADIC_DATA_BUFFERS": [""]
+          ]
         }
       ]
     },
@@ -6259,8 +6257,7 @@ func makeViewTypesWantJSONs() string {
               "SIZE": 4,
               "INLINED": "35353535"
             }
-          ],
-          "VARIADIC_DATA_BUFFERS": [""]
+          ]
         },
         {
           "name": "string_view",
@@ -6378,8 +6375,7 @@ func makeViewTypesWantJSONs() string {
               "SIZE": 2,
               "INLINED": "55"
             }
-          ],
-          "VARIADIC_DATA_BUFFERS": [""]
+          ]
         }
       ]
     }