apacheGH-35296: [Go] Add arrow.Table.String() (apache#35580)

This PR fixes apache#35296 * Closes: apache#35296 Authored-by: vibhatha <vibhatha@gmail.com> Signed-off-by: Matt Topol <zotthewizard@gmail.com>
kou · Aug 29, 2023 · f36855a · f36855a
1 parent 439d066
commit f36855a
Show file tree

Hide file tree

Showing 2 changed files with 65 additions and 0 deletions.
diff --git a/go/arrow/array/table.go b/go/arrow/array/table.go
@@ -20,6 +20,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"strings"
 	"sync/atomic"
 
 	"github.com/apache/arrow/go/v14/arrow"
@@ -257,6 +258,25 @@ func (tbl *simpleTable) Release() {
 	}
 }
 
+func (tbl *simpleTable) String() string {
+	o := new(strings.Builder)
+	o.WriteString(tbl.Schema().String())
+	o.WriteString("\n")
+
+	for i := 0; i < int(tbl.NumCols()); i++ {
+		col := tbl.Column(i)
+		o.WriteString(col.Field().Name + ": [")
+		for j, chunk := range col.Data().Chunks() {
+			if j != 0 {
+				o.WriteString(", ")
+			}
+			o.WriteString(chunk.String())
+		}
+		o.WriteString("]\n")
+	}
+	return o.String()
+}
+
 // TableReader is a Record iterator over a (possibly chunked) Table
 type TableReader struct {
 	refCount int64

diff --git a/go/arrow/array/table_test.go b/go/arrow/array/table_test.go
@@ -786,3 +786,48 @@ func TestTableReader(t *testing.T) {
 		})
 	}
 }
+
+func TestTableToString(t *testing.T) {
+	mem := memory.NewCheckedAllocator(memory.NewGoAllocator())
+	defer mem.AssertSize(t, 0)
+
+	schema := arrow.NewSchema(
+		[]arrow.Field{
+			{Name: "f1-i32", Type: arrow.PrimitiveTypes.Int32},
+			{Name: "f2-f64", Type: arrow.PrimitiveTypes.Float64},
+		},
+		nil,
+	)
+
+	b := array.NewRecordBuilder(mem, schema)
+	defer b.Release()
+
+	b.Field(0).(*array.Int32Builder).AppendValues([]int32{1, 2, 3, 4, 5, 6}, nil)
+	b.Field(0).(*array.Int32Builder).AppendValues([]int32{7, 8, 9, 10}, []bool{true, true, false, true})
+	b.Field(1).(*array.Float64Builder).AppendValues([]float64{11, 12, 13, 14, 15, 16, 17, 18, 19, 20}, nil)
+
+	rec1 := b.NewRecord()
+	defer rec1.Release()
+
+	b.Field(0).(*array.Int32Builder).AppendValues([]int32{111, 112, 113, 114, 115, 116, 117, 118, 119, 120}, nil)
+	b.Field(1).(*array.Float64Builder).AppendValues([]float64{211, 212, 213, 214, 215, 216, 217, 218, 219, 220}, nil)
+
+	rec2 := b.NewRecord()
+	defer rec2.Release()
+
+	tbl := array.NewTableFromRecords(schema, []arrow.Record{rec1, rec2})
+	defer tbl.Release()
+
+	table_str := tbl.String()
+	expected_str :=
+		`schema:
+  fields: 2
+    - f1-i32: type=int32
+    - f2-f64: type=float64
+f1-i32: [[1 2 3 4 5 6 7 8 (null) 10], [111 112 113 114 115 116 117 118 119 120]]
+f2-f64: [[11 12 13 14 15 16 17 18 19 20], [211 212 213 214 215 216 217 218 219 220]]
+`
+	if got, want := table_str, expected_str; table_str != expected_str {
+		t.Fatalf("invalid String: got=%#v, want=%#v", got, want)
+	}
+}