remove redundant type check

info.itemType already looks through each service entry
to find the item type.  A service nil check is redundant.
Adds a qol func for asking if an itemInfo is a driveish item.

src/pkg/backup/details/details.go

@@ -46,11 +46,7 @@ func (d *Details) add(
 
 	// Use the item name and the path for the ShortRef. This ensures that renames
 	// within a directory generate unique ShortRefs.
-	if info.infoType() == OneDriveItem || info.infoType() == SharePointLibrary {
+	if info.isDriveItem() {
-		if info.OneDrive == nil && info.SharePoint == nil {
-			return entry, clues.New("item is not SharePoint or OneDrive type")
-		}
-
 		// clean metadata suffixes from item refs
 		entry.ItemRef = withoutMetadataSuffix(entry.ItemRef)
 	}

src/pkg/backup/details/iteminfo.go

@@ -182,3 +182,14 @@ func (i ItemInfo) updateFolder(f *FolderInfo) error {
 		return clues.New("unsupported type")
 	}
 }
+
+// true if the info represents an item backed by the drive api.
+func (i ItemInfo) isDriveItem() bool {
+	iit := i.infoType()
+
+	if !(iit == OneDriveItem || iit == SharePointLibrary) {
+		return false
+	}
+
+	return !(i.OneDrive == nil && i.SharePoint == nil && i.Groups == nil)
+}

src/pkg/backup/details/iteminfo_test.go

@@ -0,0 +1,86 @@
+package details
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/suite"
+
+	"github.com/alcionai/corso/src/internal/tester"
+)
+
+type ItemInfoUnitSuite struct {
+	tester.Suite
+}
+
+func TestItemInfoUnitSuite(t *testing.T) {
+	suite.Run(t, &ItemInfoUnitSuite{Suite: tester.NewUnitSuite(t)})
+}
+
+func (suite *ItemInfoUnitSuite) TestItemInfo_IsDriveItem() {
+	table := []struct {
+		name   string
+		ii     ItemInfo
+		expect assert.BoolAssertionFunc
+	}{
+		{
+			name: "onedrive item",
+			ii: ItemInfo{
+				OneDrive: &OneDriveInfo{
+					ItemType: OneDriveItem,
+				},
+			},
+			expect: assert.True,
+		},
+		{
+			name: "sharepoint library",
+			ii: ItemInfo{
+				SharePoint: &SharePointInfo{
+					ItemType: SharePointLibrary,
+				},
+			},
+			expect: assert.True,
+		},
+		{
+			name: "sharepoint page",
+			ii: ItemInfo{
+				SharePoint: &SharePointInfo{
+					ItemType: SharePointPage,
+				},
+			},
+			expect: assert.False,
+		},
+		{
+			name: "groups library",
+			ii: ItemInfo{
+				Groups: &GroupsInfo{
+					ItemType: SharePointLibrary,
+				},
+			},
+			expect: assert.True,
+		},
+		{
+			name: "groups channel message",
+			ii: ItemInfo{
+				Groups: &GroupsInfo{
+					ItemType: GroupsChannelMessage,
+				},
+			},
+			expect: assert.False,
+		},
+		{
+			name: "exchange anything",
+			ii: ItemInfo{
+				Groups: &GroupsInfo{
+					ItemType: ExchangeMail,
+				},
+			},
+			expect: assert.False,
+		},
+	}
+	for _, test := range table {
+		suite.Run(test.name, func() {
+			test.expect(suite.T(), test.ii.isDriveItem())
+		})
+	}
+}