Add custom encoding for documents

internal/database/encoding_test.go

@@ -0,0 +1,90 @@
+package database_test
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/genjidb/genji/document"
+	"github.com/genjidb/genji/internal/database"
+	"github.com/genjidb/genji/internal/expr"
+	"github.com/genjidb/genji/internal/testutil"
+	"github.com/genjidb/genji/types"
+	"github.com/stretchr/testify/require"
+)
+
+func TestEncoding(t *testing.T) {
+	var ti database.TableInfo
+
+	err := ti.AddFieldConstraint(&database.FieldConstraint{
+		Position: 0,
+		Field:    "a",
+		Type:     types.IntegerValue,
+	})
+	require.NoError(t, err)
+
+	err = ti.AddFieldConstraint(&database.FieldConstraint{
+		Position: 1,
+		Field:    "b",
+		Type:     types.TextValue,
+	})
+	require.NoError(t, err)
+
+	err = ti.AddFieldConstraint(&database.FieldConstraint{
+		Position:  2,
+		Field:     "c",
+		Type:      types.DoubleValue,
+		IsNotNull: true,
+	})
+	require.NoError(t, err)
+
+	err = ti.AddFieldConstraint(&database.FieldConstraint{
+		Position:     3,
+		Field:        "d",
+		Type:         types.DoubleValue,
+		DefaultValue: expr.Constraint(testutil.ParseExpr(t, `10`)),
+	})
+	require.NoError(t, err)
+
+	err = ti.AddFieldConstraint(&database.FieldConstraint{
+		Position: 4,
+		Field:    "e",
+		Type:     types.DoubleValue,
+	})
+	require.NoError(t, err)
+
+	ti.FieldConstraints.AllowExtraFields = true
+
+	codec := database.NewCodec(nil, &ti)
+
+	doc := document.NewFromMap(map[string]any{
+		"a":     int64(1),
+		"b":     "hello",
+		"c":     float64(3.14),
+		"e":     int64(100),
+		"f":     int64(1000),
+		"g":     float64(2000),
+		"array": []int{1, 2, 3},
+		"doc":   document.NewFromMap(map[string]int64{"a": 10}),
+	})
+
+	var buf bytes.Buffer
+	err = codec.Encode(&buf, doc)
+	require.NoError(t, err)
+
+	d, err := codec.Decode(buf.Bytes())
+	require.NoError(t, err)
+
+	want := document.NewFromMap(map[string]any{
+		"a":     int64(1),
+		"b":     "hello",
+		"c":     float64(3.14),
+		"d":     float64(10),
+		"e":     float64(100),
+		"f":     float64(1000),
+		"g":     float64(2000),
+		"array": []float64{1, 2, 3},
+		"doc":   document.NewFromMap(map[string]float64{"a": 10}),
+	})
+
+	testutil.RequireDocEqual(t, want, d)
+}