Test helper functions for selector creation (#1163)

## Description

Mostly path manipulations here to allow creating selectors for a backup and paths for the output of a backup given some information about the input. Capable of working for OneDrive and Exchange.

## Type of change

<!--- Please check the type of change your PR introduces: --->
- [x] 🌻 Feature
- [ ] 🐛 Bugfix
- [ ] 🗺️ Documentation
- [ ] 🤖 Test
- [ ] 💻 CI/Deployment
- [ ] 🐹 Trivial/Minor

## Issue(s)

* #913 

## Test Plan

<!-- How will this be tested prior to merging.-->
- [ ] 💪 Manual
- [x] ⚡ Unit test
- [ ] 💚 E2E

src/internal/connector/graph_connector_helper_test.go

@@ -660,6 +660,151 @@ func checkCollections(
 	assert.Equal(t, expectedItems, gotItems, "expected items")
 }
 
+func mustParsePath(t *testing.T, p string, isItem bool) path.Path {
+	res, err := path.FromDataLayerPath(p, isItem)
+	require.NoError(t, err)
+
+	return res
+}
+
+func makeExchangeBackupSel(
+	t *testing.T,
+	expected map[string]map[string][]byte,
+) selectors.Selector {
+	sel := selectors.NewExchangeBackup()
+	toInclude := [][]selectors.ExchangeScope{}
+
+	for p := range expected {
+		pth := mustParsePath(t, p, false)
+		require.Equal(t, path.ExchangeService.String(), pth.Service().String())
+
+		switch pth.Category() {
+		case path.EmailCategory:
+			toInclude = append(toInclude, sel.MailFolders(
+				[]string{pth.ResourceOwner()},
+				[]string{backupInputFromPath(pth).String()},
+			))
+		case path.ContactsCategory:
+			toInclude = append(toInclude, sel.ContactFolders(
+				[]string{pth.ResourceOwner()},
+				[]string{backupInputFromPath(pth).String()},
+			))
+		case path.EventsCategory:
+			toInclude = append(toInclude, sel.EventCalendars(
+				[]string{pth.ResourceOwner()},
+				[]string{backupInputFromPath(pth).String()},
+			))
+		}
+	}
+
+	sel.Include(toInclude...)
+
+	return sel.Selector
+}
+
+func makeOneDriveBackupSel(
+	t *testing.T,
+	expected map[string]map[string][]byte,
+) selectors.Selector {
+	sel := selectors.NewOneDriveBackup()
+	toInclude := [][]selectors.OneDriveScope{}
+
+	for p := range expected {
+		pth := mustParsePath(t, p, false)
+		require.Equal(t, path.OneDriveService.String(), pth.Service().String())
+
+		toInclude = append(toInclude, sel.Folders(
+			[]string{pth.ResourceOwner()},
+			[]string{backupInputFromPath(pth).String()},
+		))
+	}
+
+	sel.Include(toInclude...)
+
+	return sel.Selector
+}
+
+// backupSelectorForExpected creates a selector that can be used to backup the
+// given items in expected based on the item paths. Fails the test if items from
+// multiple services are in expected.
+func backupSelectorForExpected(
+	t *testing.T,
+	expected map[string]map[string][]byte,
+) selectors.Selector {
+	require.NotEmpty(t, expected)
+
+	// Sadly need to get the first item to figure out what sort of selector we
+	// need.
+	for p := range expected {
+		pth := mustParsePath(t, p, false)
+
+		switch pth.Service() {
+		case path.ExchangeService:
+			return makeExchangeBackupSel(t, expected)
+		case path.OneDriveService:
+			return makeOneDriveBackupSel(t, expected)
+		default:
+			assert.FailNowf(t, "bad serivce type %s", pth.Service().String())
+		}
+	}
+
+	// Fix compile error about no return. Should not reach here.
+	return selectors.Selector{}
+}
+
+// backupInputFromPath returns a path.Builder with the path that a call to Backup
+// can use to backup the given items.
+func backupInputFromPath(
+	inputPath path.Path,
+) *path.Builder {
+	startIdx := 0
+
+	if inputPath.Service() == path.OneDriveService {
+		// OneDrive has folders that are trimmed off in the app that are present in
+		// Corso.
+		startIdx = 3
+	}
+
+	return path.Builder{}.Append(inputPath.Folders()[startIdx:]...)
+}
+
+// backupOutputPathFromRestore returns a path.Path denoting the location in
+// kopia the data will be placed at. The location is a data-type specific
+// combination of the location the data was recently restored to and where the
+// data was originally in the hierarchy.
+func backupOutputPathFromRestore(
+	t *testing.T,
+	restoreDest control.RestoreDestination,
+	inputPath path.Path,
+) path.Path {
+	base := []string{restoreDest.ContainerName}
+
+	// OneDrive has leading information like the drive ID.
+	if inputPath.Service() == path.OneDriveService {
+		folders := inputPath.Folders()
+		base = append(append([]string{}, folders[:3]...), restoreDest.ContainerName)
+
+		if len(folders) > 3 {
+			base = append(base, folders[3:]...)
+		}
+	}
+
+	// TODO(ashmrtn): Uncomment when exchange mail supports restoring to subfolders.
+	// if inputPath.Service == path.ExchangeService && inputPath.Category() == path.EmailCategory {
+	//   base = append(base, inputPath.Folders()...)
+	// }
+
+	return mustToDataLayerPath(
+		t,
+		inputPath.Service(),
+		inputPath.Tenant(),
+		inputPath.ResourceOwner(),
+		inputPath.Category(),
+		base,
+		false,
+	)
+}
+
 func collectionsForInfo(
 	t *testing.T,
 	service path.ServiceType,
@@ -682,19 +827,7 @@ func collectionsForInfo(
 			false,
 		)
 		c := mockconnector.NewMockExchangeCollection(pth, len(info.items))
-
-		// TODO(ashmrtn): This will need expanded/broken up by service/category
-		// depending on how restore for that service/category places data back in
-		// M365.
-		baseDestPath := mustToDataLayerPath(
-			t,
-			service,
-			tenant,
-			user,
-			info.category,
-			[]string{dest.ContainerName},
-			false,
-		)
+		baseDestPath := backupOutputPathFromRestore(t, dest, pth)
 
 		baseExpected := expectedData[baseDestPath.String()]
 		if baseExpected == nil {

src/internal/connector/graph_connector_test.go

@@ -457,7 +457,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 		name                   string
 		service                path.ServiceType
 		collections            []colInfo
-		backupSelFunc          func(dest control.RestoreDestination, backupUser string) selectors.Selector
 		expectedRestoreFolders int
 	}{
 		{
@@ -486,17 +485,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.MailFolders(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 		{
 			name:                   "MultipleEmailsSingleFolder",
@@ -534,17 +522,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.MailFolders(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 		{
 			name:                   "MultipleContactsSingleFolder",
@@ -573,17 +550,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.ContactFolders(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 		{
 			name:                   "MultipleContactsMutlipleFolders",
@@ -628,17 +594,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.ContactFolders(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 		{
 			name:                   "MultipleEventsSingleCalendar",
@@ -667,17 +622,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.EventCalendars(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 		{
 			name:                   "MultipleEventsMultipleCalendars",
@@ -722,17 +666,6 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 					},
 				},
 			},
-			// TODO(ashmrtn): Generalize this once we know the path transforms that
-			// occur during restore.
-			backupSelFunc: func(dest control.RestoreDestination, backupUser string) selectors.Selector {
-				backupSel := selectors.NewExchangeBackup()
-				backupSel.Include(backupSel.EventCalendars(
-					[]string{backupUser},
-					[]string{dest.ContainerName},
-				))
-
-				return backupSel.Selector
-			},
 		},
 	}
 
@@ -774,7 +707,7 @@ func (suite *GraphConnectorIntegrationSuite) TestRestoreAndBackup() {
 			// Run a backup and compare its output with what we put in.
 
 			backupGC := loadConnector(ctx, t)
-			backupSel := test.backupSelFunc(dest, suite.user)
+			backupSel := backupSelectorForExpected(t, expectedData)
 			t.Logf("Selective backup of %s\n", backupSel)
 
 			dcs, err := backupGC.DataCollections(ctx, backupSel)
@@ -800,41 +733,6 @@ func (suite *GraphConnectorIntegrationSuite) TestMultiFolderBackupDifferentNames
 	bodyText := "This email has some text. However, all the text is on the same line."
 	subjectText := "Test message for restore"
 
-	// TODO(ashmrtn): Update if we start mixing categories during backup/restore.
-	backupSelFunc := func(
-		dests []control.RestoreDestination,
-		category path.CategoryType,
-		backupUser string,
-	) selectors.Selector {
-		destNames := make([]string, 0, len(dests))
-
-		for _, d := range dests {
-			destNames = append(destNames, d.ContainerName)
-		}
-
-		backupSel := selectors.NewExchangeBackup()
-
-		switch category {
-		case path.EmailCategory:
-			backupSel.Include(backupSel.MailFolders(
-				[]string{backupUser},
-				destNames,
-			))
-		case path.ContactsCategory:
-			backupSel.Include(backupSel.ContactFolders(
-				[]string{backupUser},
-				destNames,
-			))
-		case path.EventsCategory:
-			backupSel.Include(backupSel.EventCalendars(
-				[]string{backupUser},
-				destNames,
-			))
-		}
-
-		return backupSel.Selector
-	}
-
 	table := []struct {
 		name     string
 		service  path.ServiceType
@@ -994,7 +892,7 @@ func (suite *GraphConnectorIntegrationSuite) TestMultiFolderBackupDifferentNames
 			// Run a backup and compare its output with what we put in.
 
 			backupGC := loadConnector(ctx, t)
-			backupSel := backupSelFunc(dests, test.category, suite.user)
+			backupSel := backupSelectorForExpected(t, allExpectedData)
 			t.Logf("Selective backup of %s\n", backupSel)
 
 			dcs, err := backupGC.DataCollections(ctx, backupSel)