remove common maps, add golang maps (#1885)

## Description

replaces the common/maps.go code with the
golang experimental maps package. The
maps package provides standard api
such as Keys, Values, Copy, and Clone.

https://pkg.go.dev/golang.org/x/exp/maps

## Does this PR need a docs update or release note?

- [x] ⛔ No 

## Type of change

- [x] 🐹 Trivial/Minor

## Test Plan

- [x] ⚡ Unit test

src/go.mod

@@ -25,6 +25,7 @@ require (
 	github.com/tomlazar/table v0.1.2
 	github.com/vbauerster/mpb/v8 v8.1.4
 	go.uber.org/zap v1.24.0
+	golang.org/x/exp v0.0.0-20221217163422-3c43f8badb15
 	golang.org/x/tools v0.4.0
 	gopkg.in/resty.v1 v1.12.0
 )

src/go.sum

@@ -444,6 +444,8 @@ golang.org/x/exp v0.0.0-20191227195350-da58074b4299/go.mod h1:2RIsYlXP63K8oxa1u0
 golang.org/x/exp v0.0.0-20200119233911-0405dc783f0a/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EHIKF9dgMWnmCNThgcyBT1FY9mM=
 golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6/go.mod h1:3jZMyOhIsHpP37uCMkUooju7aAi5cS1Q23tOzKc+0MU=
+golang.org/x/exp v0.0.0-20221217163422-3c43f8badb15 h1:5oN1Pz/eDhCpbMbLstvIPa0b/BEQo6g6nwV3pLjfM6w=
+golang.org/x/exp v0.0.0-20221217163422-3c43f8badb15/go.mod h1:CxIveKay+FTh1D0yPZemJVgC/95VzuuOLq5Qi4xnoYc=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=

src/internal/common/configs.go

@@ -1,5 +1,7 @@
 package common
 
+import "golang.org/x/exp/maps"
+
 type StringConfigurer interface {
 	StringConfig() (map[string]string, error)
 }
@@ -15,9 +17,7 @@ func UnionStringConfigs(cfgs ...StringConfigurer) (map[string]string, error) {
 			return nil, err
 		}
 
-		for k, v := range c {
-			union[k] = v
-		}
+		maps.Copy(union, c)
 	}
 
 	return union, nil

src/internal/common/maps.go

@@ -1,26 +0,0 @@
-package common
-
-// UnionMaps produces a new map containing all the values of the other
-// maps.  The last maps have the highes priority.  Key collisions with
-// earlier maps will favor the last map with that key.
-func UnionMaps[K comparable, V any](ms ...map[K]V) map[K]V {
-	r := map[K]V{}
-
-	for _, m := range ms {
-		for k, v := range m {
-			r[k] = v
-		}
-	}
-
-	return r
-}
-
-func CopyMap[K comparable, V any](m map[K]V) map[K]V {
-	r := map[K]V{}
-
-	for k, v := range m {
-		r[k] = v
-	}
-
-	return r
-}

src/internal/connector/exchange/service_iterators.go

@@ -11,7 +11,6 @@ import (
 	msuser "github.com/microsoftgraph/msgraph-sdk-go/users"
 	"github.com/pkg/errors"
 
-	"github.com/alcionai/corso/src/internal/common"
 	"github.com/alcionai/corso/src/internal/connector/graph"
 	"github.com/alcionai/corso/src/internal/connector/support"
 	"github.com/alcionai/corso/src/internal/data"
@@ -62,7 +61,7 @@ func filterContainersAndFillCollections(
 		currPaths = map[string]string{}
 		// copy of previousPaths.  any folder found in the resolver get
 		// deleted from this map, leaving only the deleted maps behind
-		deletedPaths = common.CopyMap(dps)
+		deletedPaths = map[string]DeltaPath{}
 	)
 
 	getJobs, err := getFetchIDFunc(qp.Category)

src/internal/connector/graph_connector.go

@@ -12,6 +12,7 @@ import (
 	msgraphgocore "github.com/microsoftgraph/msgraph-sdk-go-core"
 	"github.com/microsoftgraph/msgraph-sdk-go/models"
 	"github.com/pkg/errors"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/internal/connector/discovery"
 	"github.com/alcionai/corso/src/internal/connector/exchange"
@@ -136,12 +137,12 @@ func (gc *GraphConnector) setTenantUsers(ctx context.Context) error {
 
 // GetUsers returns the email address of users within the tenant.
 func (gc *GraphConnector) GetUsers() []string {
-	return buildFromMap(true, gc.Users)
+	return maps.Keys(gc.Users)
 }
 
 // GetUsersIds returns the M365 id for the user
 func (gc *GraphConnector) GetUsersIds() []string {
-	return buildFromMap(false, gc.Users)
+	return maps.Values(gc.Users)
 }
 
 // setTenantSites queries the M365 to identify the sites in the
@@ -202,12 +203,12 @@ func identifySite(item any) (string, string, error) {
 
 // GetSiteWebURLs returns the WebURLs of sharepoint sites within the tenant.
 func (gc *GraphConnector) GetSiteWebURLs() []string {
-	return buildFromMap(true, gc.Sites)
+	return maps.Keys(gc.Sites)
 }
 
 // GetSiteIds returns the canonical site IDs in the tenant
 func (gc *GraphConnector) GetSiteIDs() []string {
-	return buildFromMap(false, gc.Sites)
+	return maps.Values(gc.Sites)
 }
 
 // UnionSiteIDsAndWebURLs reduces the id and url slices into a single slice of site IDs.
@@ -246,24 +247,6 @@ func (gc *GraphConnector) UnionSiteIDsAndWebURLs(ctx context.Context, ids, urls
 	return idsl, nil
 }
 
-// buildFromMap helper function for returning []string from map.
-// Returns list of keys iff true; otherwise returns a list of values
-func buildFromMap(isKey bool, mapping map[string]string) []string {
-	returnString := make([]string, 0)
-
-	if isKey {
-		for k := range mapping {
-			returnString = append(returnString, k)
-		}
-	} else {
-		for _, v := range mapping {
-			returnString = append(returnString, v)
-		}
-	}
-
-	return returnString
-}
-
 // RestoreDataCollections restores data from the specified collections
 // into M365 using the GraphAPI.
 // SideEffect: gc.status is updated at the completion of operation

src/internal/connector/graph_connector_disconnected_test.go

@@ -72,22 +72,6 @@ func (suite *DisconnectedGraphConnectorSuite) TestBadConnection() {
 	}
 }
 
-func (suite *DisconnectedGraphConnectorSuite) TestBuild() {
-	names := make(map[string]string)
-	names["Al"] = "Bundy"
-	names["Ellen"] = "Ripley"
-	names["Axel"] = "Foley"
-	first := buildFromMap(true, names)
-	last := buildFromMap(false, names)
-
-	suite.Contains(first, "Al")
-	suite.Contains(first, "Ellen")
-	suite.Contains(first, "Axel")
-	suite.Contains(last, "Bundy")
-	suite.Contains(last, "Ripley")
-	suite.Contains(last, "Foley")
-}
-
 func statusTestTask(gc *GraphConnector, objects, success, folder int) {
 	ctx, flush := tester.NewContext()
 	defer flush()

src/internal/connector/graph_connector_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/internal/connector/graph"
 	"github.com/alcionai/corso/src/internal/connector/mockconnector"
@@ -336,9 +337,7 @@ func runRestoreBackupTest(
 		collections = append(collections, userCollections...)
 		totalItems += numItems
 
-		for k, v := range userExpectedData {
-			expectedData[k] = v
-		}
+		maps.Copy(expectedData, userExpectedData)
 	}
 
 	t.Logf(

src/internal/kopia/model_store.go

@@ -8,6 +8,7 @@ import (
 	"github.com/kopia/kopia/repo"
 	"github.com/kopia/kopia/repo/manifest"
 	"github.com/pkg/errors"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/internal/model"
 )
@@ -64,9 +65,7 @@ func tagsForModel(s model.Schema, tags map[string]string) (map[string]string, er
 	res := make(map[string]string, len(tags)+1)
 	res[manifest.TypeLabelKey] = s.String()
 
-	for k, v := range tags {
-		res[k] = v
-	}
+	maps.Copy(res, tags)
 
 	return res, nil
 }

src/internal/kopia/snapshot_manager.go

@@ -7,6 +7,7 @@ import (
 	"github.com/kopia/kopia/repo/manifest"
 	"github.com/kopia/kopia/snapshot"
 	"github.com/pkg/errors"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/pkg/logger"
 	"github.com/alcionai/corso/src/pkg/path"
@@ -198,9 +199,7 @@ func fetchPrevManifests(
 		resourceOwner: "",
 	})
 
-	for k, v := range tags {
-		allTags[k] = v
-	}
+	maps.Copy(allTags, tags)
 
 	reason := Reason{
 		ResourceOwner: resourceOwner,

src/internal/kopia/wrapper_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/internal/connector/mockconnector"
 	"github.com/alcionai/corso/src/internal/data"
@@ -241,9 +242,7 @@ func (suite *KopiaIntegrationSuite) TestBackupCollections() {
 		expectedTags[tk] = tv
 	}
 
-	for k, v := range normalizeTagKVs(customTags) {
-		expectedTags[k] = v
-	}
+	maps.Copy(expectedTags, normalizeTagKVs(customTags))
 
 	table := []struct {
 		name                  string

src/internal/tester/config.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/spf13/viper"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/pkg/account"
 )
@@ -48,12 +49,7 @@ func cloneTestConfig() map[string]string {
 		return map[string]string{}
 	}
 
-	clone := map[string]string{}
-	for k, v := range testConfig {
-		clone[k] = v
-	}
-
-	return clone
+	return maps.Clone(testConfig)
 }
 
 func NewTestViper() (*viper.Viper, error) {

src/internal/tester/envvars.go

@@ -3,6 +3,8 @@ package tester
 import (
 	"errors"
 	"os"
+
+	"golang.org/x/exp/maps"
 )
 
 // GetRequiredEnvVars retrieves the provided env vars from the os.
@@ -35,9 +37,7 @@ func GetRequiredEnvSls(evs ...[]string) (map[string]string, error) {
 			return nil, err
 		}
 
-		for k, v := range r {
-			vals[k] = v
-		}
+		maps.Copy(vals, r)
 	}
 
 	return vals, nil

src/pkg/selectors/scopes.go

@@ -3,6 +3,8 @@ package selectors
 import (
 	"context"
 
+	"golang.org/x/exp/maps"
+
 	D "github.com/alcionai/corso/src/internal/diagnostics"
 	"github.com/alcionai/corso/src/pkg/backup/details"
 	"github.com/alcionai/corso/src/pkg/filters"
@@ -250,11 +252,7 @@ func set[T scopeT](s T, cat categorizer, v []string, opts ...option) T {
 // discreteCopy makes a shallow clone of the scocpe, and sets the resource
 // owner filter target in the clone to the provided string.
 func discreteCopy[T scopeT](s T, resourceOwner string) T {
-	clone := T{}
-
-	for k, v := range s {
-		clone[k] = v
-	}
+	clone := maps.Clone(s)
 
 	return set(
 		clone,

src/pkg/selectors/selectors.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
+	"golang.org/x/exp/maps"
 
 	"github.com/alcionai/corso/src/pkg/backup/details"
 	"github.com/alcionai/corso/src/pkg/filters"
@@ -185,11 +186,7 @@ func discreteScopes[T scopeT, C categoryT](
 		t := T(v)
 
 		if isAnyTarget(t, rootCat) {
-			w := T{}
-			for k, v := range t {
-				w[k] = v
-			}
-
+			w := maps.Clone(t)
 			set(w, rootCat, discreteIDs)
 			t = w
 		}