Added RS first (#2)

Added the `First` field on the result set proxy
Upgraded UCL to 0.1.0

Co-authored-by: Leon Mika <lmika@lmika.com>
Reviewed-on: #2
Co-authored-by: Leon Mika <lmika@lmika.org>
Co-committed-by: Leon Mika <lmika@lmika.org>

internal/common/ui/commandctrl/cmdpacks/modpb_test.go

@@ -1,8 +1,9 @@
 package cmdpacks_test
 
 import (
-	"github.com/stretchr/testify/assert"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestModPB_Copy(t *testing.T) {
@@ -10,8 +11,8 @@ func TestModPB_Copy(t *testing.T) {
 		svc := newService(t)
 
 		_, err := svc.CommandController.ExecuteAndWait(t.Context(), `
-			$items = @resultset.Items
-			$skItems = $items | map { |i| $i.sk } | lists:uniq
+			items = @resultset.Items
+			skItems = $items | map { |i| $i.sk } | lists:uniq
 			pb:copy ($skItems | strs:join "\n")
 		`)
 		assert.NoError(t, err)
@@ -23,8 +24,8 @@ func TestModPB_Copy(t *testing.T) {
 		svc := newService(t)
 
 		_, err := svc.CommandController.ExecuteAndWait(t.Context(), `
-			$items = @resultset.Items
-			$skItems = $items | map { |i| $i.alpha } | filter !nil | lists:uniq
+			items = @resultset.Items
+			skItems = $items | map { |i| $i.alpha } | filter !nil | lists:uniq
 			pb:copy ($skItems | strs:join "\n")
 		`)
 		assert.NoError(t, err)

internal/common/ui/commandctrl/cmdpacks/modrs_test.go

@@ -2,10 +2,11 @@ package cmdpacks_test
 
 import (
 	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
 	"lmika.dev/cmd/dynamo-browse/internal/common/ui/commandctrl/cmdpacks"
 	"lmika.dev/cmd/dynamo-browse/internal/dynamo-browse/models"
-	"github.com/stretchr/testify/assert"
-	"testing"
 )
 
 func TestModRS_New(t *testing.T) {
@@ -70,7 +71,7 @@ func TestModRS_Union(t *testing.T) {
 	svc := newService(t, withDefaultLimit(2))
 
 	rsProxy, err := svc.CommandController.ExecuteAndWait(t.Context(), `
-		$mr = rs:union @resultset (rs:next-page @resultset)
+		mr = rs:union @resultset (rs:next-page @resultset)
 		
 		assert (eq (len $mr.Items) 3) "expected len == 3"
 		assert (eq $mr.Items.(0).pk "abc") "expected 0.pk"
@@ -152,3 +153,41 @@ func TestModRS_Query(t *testing.T) {
 		})
 	}
 }
+
+func TestModRS_First(t *testing.T) {
+	tests := []struct {
+		descr string
+		cmd   string
+	}{
+		{
+			descr: "returns the first item in sorted order",
+			cmd: `
+				rs = rs:query 'pk="abc"' -table service-test-data
+				assert (eq $rs.First.pk "abc") "expected First.pk == abc"
+				assert (eq $rs.First.sk "111") "expected First.sk == 111"
+			`,
+		}, {
+			descr: "returns the first item in single item",
+			cmd: `
+				rs = rs:query 'pk="abc" and sk="222"' -table service-test-data
+				assert (eq $rs.First.pk "abc") "expected First.pk == abc"
+				assert (eq $rs.First.sk "222") "expected First.sk == 222"
+				assert (eq $rs.First.beta 1231) "expected First.beta == 1231"
+			`,
+		}, {
+			descr: "returns the first item in empty result",
+			cmd: `
+				rs = rs:query 'pk="zzz"' -table service-test-data
+				assert (eq $rs.First ()) "expected First to be nil"
+			`,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.descr, func(t *testing.T) {
+			svc := newService(t)
+
+			_, err := svc.CommandController.ExecuteAndWait(t.Context(), tt.cmd)
+			assert.NoError(t, err)
+		})
+	}
+}

internal/common/ui/commandctrl/cmdpacks/proxy.go

@@ -2,11 +2,12 @@ package cmdpacks
 
 import (
 	"fmt"
+	"maps"
+	"strconv"
+
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb/types"
 	"github.com/pkg/errors"
 	"lmika.dev/cmd/dynamo-browse/internal/dynamo-browse/models"
-	"maps"
-	"strconv"
 	"ucl.lmika.dev/ucl"
 )
 
@@ -99,6 +100,13 @@ var resultSetProxyFields = &proxyInfo[*models.ResultSet]{
 		"Table":       func(t *models.ResultSet) ucl.Object { return newTableProxy(t.TableInfo) },
 		"Items":       func(t *models.ResultSet) ucl.Object { return resultSetItemsProxy{t} },
 		"HasNextPage": func(t *models.ResultSet) ucl.Object { return ucl.BoolObject(t.HasNextPage()) },
+		"First": func(t *models.ResultSet) ucl.Object {
+			items := t.Items()
+			if len(items) == 0 {
+				return nil
+			}
+			return itemProxy{resultSet: t, idx: 0, item: items[0]}
+		},
 	},
 }