allow init with empty working set (#4255)

go/libraries/doltcore/env/actions/branch.go

@@ -243,6 +243,12 @@ func createBranch(ctx context.Context, dbData env.DbData, newBranch, startingPoi
 // should be the pre-checkout head. The returned roots struct has |Head| set to |branchRoot|.
 func UpdateRootsForBranch(ctx context.Context, roots doltdb.Roots, branchRoot *doltdb.RootValue, force bool) (doltdb.Roots, error) {
 	conflicts := set.NewStrSet([]string{})
+	if roots.Head == nil {
+		roots.Working = branchRoot
+		roots.Staged = branchRoot
+		roots.Head = branchRoot
+		return roots, nil
+	}
 
 	wrkTblHashes, err := moveModifiedTables(ctx, roots.Head, branchRoot, roots.Working, conflicts, force)
 	if err != nil {
@@ -314,10 +320,10 @@ func CheckoutBranch(ctx context.Context, dEnv *env.DoltEnv, brName string, force
 	}
 
 	roots, err := dEnv.Roots(ctx)
-	if errors.Is(err, doltdb.ErrBranchNotFound) {
+	// roots will be empty/nil if the working set is not set (working set is not set if the current branch was deleted)
+	if errors.Is(err, doltdb.ErrBranchNotFound) || errors.Is(err, doltdb.ErrWorkingSetNotFound) {
 		roots, err = dEnv.RecoveryRoots(ctx)
-	}
-	if err != nil {
+	} else if err != nil {
 		return err
 	}
 

go/libraries/doltcore/env/environment.go

@@ -175,11 +175,8 @@ func loadWithFormat(ctx context.Context, hdp HomeDirProvider, fs filesys.Filesys
 	if rsErr == nil && dbLoadErr == nil && dbFormatErr == nil {
 		// If the working set isn't present in the DB, create it from the repo state. This step can be removed post 1.0.
 		_, err := dEnv.WorkingSet(ctx)
-		if err == doltdb.ErrWorkingSetNotFound {
-			err := dEnv.initWorkingSetFromRepoState(ctx)
-			if err != nil {
-				dEnv.RSLoadErr = err
-			}
+		if errors.Is(err, doltdb.ErrWorkingSetNotFound) {
+			_ = dEnv.initWorkingSetFromRepoState(ctx)
 		} else if err != nil {
 			dEnv.RSLoadErr = err
 		}

go/libraries/doltcore/sqle/dfunctions/dolt_branch.go

@@ -96,9 +96,9 @@ func DoDoltBranch(ctx *sql.Context, args []string) (int, error) {
 	case apr.Contains(cli.CopyFlag):
 		err = copyBranch(ctx, dbData, apr)
 	case apr.Contains(cli.MoveFlag):
-		err = renameBranch(ctx, dbData, apr)
+		err = renameBranch(ctx, dbData, apr, dSess, dbName)
 	case apr.Contains(cli.DeleteFlag), apr.Contains(cli.DeleteForceFlag):
-		err = deleteBranches(ctx, apr, dbData)
+		err = deleteBranches(ctx, dbData, apr, dSess, dbName)
 	default:
 		err = createNewBranch(ctx, dbData, apr)
 	}
@@ -110,7 +110,9 @@ func DoDoltBranch(ctx *sql.Context, args []string) (int, error) {
 	}
 }
 
-func renameBranch(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseResults) error {
+// renameBranch takes DoltSession and database name to try accessing file system for dolt database.
+// If the oldBranch being renamed is the current branch on CLI, then RepoState head will be updated with the newBranch ref.
+func renameBranch(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseResults, sess *dsess.DoltSession, dbName string) error {
 	if apr.NArg() != 2 {
 		return InvalidArgErr
 	}
@@ -127,14 +129,46 @@ func renameBranch(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseRe
 		}
 	}
 
-	return actions.RenameBranch(ctx, dbData, loadConfig(ctx), oldBranchName, newBranchName, force)
+	err := actions.RenameBranch(ctx, dbData, loadConfig(ctx), oldBranchName, newBranchName, force)
+	if err != nil {
+		return err
+	}
+
+	// The current branch on CLI can be deleted as user can be on different branch on SQL and delete it from SQL session.
+	// To update current head info on RepoState, we need DoltEnv to load CLI environment.
+	if fs, err := sess.Provider().FileSystemForDatabase(dbName); err == nil {
+		if repoState, err := env.LoadRepoState(fs); err == nil {
+			if repoState.Head.Ref.GetPath() == oldBranchName {
+				repoState.Head.Ref = ref.NewBranchRef(newBranchName)
+				repoState.Save(fs)
+			}
+		}
+	}
+
+	return nil
 }
 
-func deleteBranches(ctx *sql.Context, apr *argparser.ArgParseResults, dbData env.DbData) error {
+// deleteBranches takes DoltSession and database name to try accessing file system for dolt database.
+// If the database is not session state db and the branch being deleted is the current branch on CLI, it will update
+// the RepoState to set head as empty branchRef.
+func deleteBranches(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseResults, sess *dsess.DoltSession, dbName string) error {
 	if apr.NArg() == 0 {
 		return InvalidArgErr
 	}
 
+	// The current branch on CLI can be deleted as user can be on different branch on SQL and delete it from SQL session.
+	// To update current head info on RepoState, we need DoltEnv to load CLI environment.
+	var rs *env.RepoState
+	var headOnCLI string
+	fs, err := sess.Provider().FileSystemForDatabase(dbName)
+	if err == nil {
+		if repoState, err := env.LoadRepoState(fs); err == nil {
+			rs = repoState
+			headOnCLI = repoState.Head.Ref.GetPath()
+		}
+	}
+
+	var updateFS = false
 	for _, branchName := range apr.Args {
 		if len(branchName) == 0 {
 			return EmptyBranchNameErr
@@ -142,19 +176,27 @@ func deleteBranches(ctx *sql.Context, apr *argparser.ArgParseResults, dbData env
 		force := apr.Contains(cli.DeleteForceFlag) || apr.Contains(cli.ForceFlag)
 
 		if !force {
-			err := validateBranchNotActiveInAnySession(ctx, branchName)
+			err = validateBranchNotActiveInAnySession(ctx, branchName)
 			if err != nil {
 				return err
 			}
 		}
-		err := actions.DeleteBranch(ctx, dbData, loadConfig(ctx), branchName, actions.DeleteOptions{
+		err = actions.DeleteBranch(ctx, dbData, loadConfig(ctx), branchName, actions.DeleteOptions{
 			Force: force,
 		})
 		if err != nil {
 			return err
 		}
-
+		if headOnCLI == branchName {
+			updateFS = true
+		}
 	}
+
+	if fs != nil && updateFS {
+		rs.Head.Ref = ref.NewBranchRef("")
+		rs.Save(fs)
+	}
+
 	return nil
 }
 
@@ -220,16 +262,23 @@ func loadConfig(ctx *sql.Context) *env.DoltCliConfig {
 }
 
 func createNewBranch(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseResults) error {
-	if apr.NArg() != 1 {
-		return InvalidArgErr
+	var branchName string
+	var startPt = "HEAD"
+	if apr.NArg() == 1 {
+		branchName = apr.Arg(0)
+	} else if apr.NArg() == 2 {
+		branchName = apr.Arg(0)
+		startPt = apr.Arg(1)
+		if len(startPt) == 0 {
+			return InvalidArgErr
+		}
 	}
 
-	branchName := apr.Arg(0)
 	if len(branchName) == 0 {
 		return EmptyBranchNameErr
 	}
 
-	return actions.CreateBranchWithStartPt(ctx, dbData, branchName, "HEAD", apr.Contains(cli.ForceFlag))
+	return actions.CreateBranchWithStartPt(ctx, dbData, branchName, startPt, apr.Contains(cli.ForceFlag))
 }
 
 func copyBranch(ctx *sql.Context, dbData env.DbData, apr *argparser.ArgParseResults) error {

go/libraries/doltcore/sqle/dtables/branches_table.go

@@ -15,13 +15,12 @@
 package dtables
 
 import (
-	"errors"
+	"fmt"
 	"io"
 
 	"github.com/dolthub/go-mysql-server/sql"
 
 	"github.com/dolthub/dolt/go/libraries/doltcore/doltdb"
-	"github.com/dolthub/dolt/go/libraries/doltcore/ref"
 	"github.com/dolthub/dolt/go/libraries/doltcore/sqle/index"
 )
 
@@ -177,86 +176,23 @@ type branchWriter struct {
 	bt *BranchesTable
 }
 
-func branchAndHashFromRow(r sql.Row) (string, string, error) {
-	branchName, ok := r[0].(string)
-
-	if !ok {
-		return "", "", errors.New("invalid value type for branch")
-	} else if !doltdb.IsValidUserBranchName(branchName) {
-		return "", "", doltdb.ErrInvBranchName
-	}
-
-	commitHash, ok := r[1].(string)
-
-	if !ok {
-		return "", "", errors.New("invalid value type for hash")
-	}
-
-	return branchName, commitHash, nil
-}
-
 // Insert inserts the row given, returning an error if it cannot. Insert will be called once for each row to process
 // for the insert operation, which may involve many rows. After all rows in an operation have been processed, Close
 // is called.
 func (bWr branchWriter) Insert(ctx *sql.Context, r sql.Row) error {
-	branchName, commitHash, err := branchAndHashFromRow(r)
-
-	if err != nil {
-		return err
-	}
-
-	cs, err := doltdb.NewCommitSpec(commitHash)
-
-	if err != nil {
-		return err
-	}
-
-	ddb := bWr.bt.ddb
-	cm, err := ddb.Resolve(ctx, cs, nil)
-
-	if err != nil {
-		return err
-	}
-
-	branchRef := ref.NewBranchRef(branchName)
-
-	// TODO: this isn't safe in a SQL context, since we have to update the working set of the new branch and it's a
-	//  race. It needs to be able to retry the same as committing a transaction.
-	err = ddb.NewBranchAtCommit(ctx, branchRef, cm)
-	if err != nil {
-		return err
-	}
-
-	return bWr.bt.ddb.ExecuteCommitHooks(ctx, branchRef.String())
+	return fmt.Errorf("the dolt_branches table is read-only; use the dolt_branch stored procedure to edit remotes")
 }
 
 // Update the given row. Provides both the old and new rows.
 func (bWr branchWriter) Update(ctx *sql.Context, old sql.Row, new sql.Row) error {
-	return bWr.Insert(ctx, new)
+	return fmt.Errorf("the dolt_branches table is read-only; use the dolt_branch stored procedure to edit remotes")
 }
 
 // Delete deletes the given row. Returns ErrDeleteRowNotFound if the row was not found. Delete will be called once for
 // each row to process for the delete operation, which may involve many rows. After all rows have been processed,
 // Close is called.
 func (bWr branchWriter) Delete(ctx *sql.Context, r sql.Row) error {
-	branchName, _, err := branchAndHashFromRow(r)
-
-	if err != nil {
-		return err
-	}
-
-	brRef := ref.NewBranchRef(branchName)
-	exists, err := bWr.bt.ddb.HasRef(ctx, brRef)
-
-	if err != nil {
-		return err
-	}
-
-	if !exists {
-		return sql.ErrDeleteRowNotFound.New()
-	}
-
-	return bWr.bt.ddb.DeleteBranch(ctx, brRef)
+	return fmt.Errorf("the dolt_branches table is read-only; use the dolt_branch stored procedure to edit remotes")
 }
 
 // StatementBegin implements the interface sql.TableEditor. Currently a no-op.

go/libraries/doltcore/sqle/enginetest/dolt_harness.go

@@ -453,7 +453,7 @@ func (d *DoltHarness) SnapshotTable(db sql.VersionedDatabase, name string, asOf
 	// TODO: there's a bug in test setup with transactions, where the HEAD session var gets overwritten on transaction
 	//  start, so we quote it here instead
 	// query := "insert into dolt_branches (name, hash) values ('" + asOfString + "', @@" + dsess.HeadKey(ddb.Name()) + ")"
-	query := "insert into dolt_branches (name, hash) values ('" + asOfString + "', '" + headHash.(string) + "')"
+	query := "CALL dolt_branch('" + asOfString + "', '" + headHash.(string) + "')"
 
 	_, iter, err = e.Query(ctx,
 		query)

go/libraries/doltcore/sqle/enginetest/dolt_queries.go

@@ -2199,7 +2199,7 @@ var MergeScripts = []queries.ScriptTest{
 			"CREATE TRIGGER trigger1 BEFORE INSERT ON x FOR EACH ROW SET new.a = new.a + 1",
 			"CALL dolt_add('-A')",
 			"CALL dolt_commit('-m', 'added table with trigger')",
-			"INSERT INTO dolt_branches (name, hash) VALUES ('other',hashof('main'))",
+			"CALL dolt_branch('-c', 'main', 'other')",
 			// create trigger2 on main
 			"CREATE TRIGGER trigger2 BEFORE INSERT ON x FOR EACH ROW SET new.a = (new.a * 2) + 10",
 			"CALL dolt_commit('-am', 'created trigger2 on main')",

integration-tests/bats/deleted-branches.bats

@@ -21,16 +21,45 @@ make_it() {
     dolt branch -c main to_keep
 }
 
-@test "deleted-branches: can checkout existing branch after checked out branch is deleted" {
+@test "deleted-branches: can checkout existing branch after checked out branch on CLI is deleted" {
     make_it
 
-    dolt sql -q 'delete from dolt_branches where name = "main"'
+    run dolt status
+    [[ "$output" =~ "On branch main" ]] || false
+
+    run dolt sql -q 'call dolt_branch("-D", "main");'
+    [ $status -eq 1 ]
+    [[ "$output" =~ "attempted to delete checked out branch" ]] || false
+
+    dolt sql -q 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");'
 
     dolt branch -av
 
     dolt checkout to_keep
 }
 
+@test "deleted-branches: attempt to delete the last branch when currently on no branch" {
+    make_it
+
+    dolt sql -q 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");'
+
+    dolt branch -av
+
+    run dolt branch -D to_keep
+    [[ "$output" =~ "cannot delete the last branch" ]] || false
+}
+
+@test "deleted-branches: renaming current branch on CLI deletes that branch and sets the current branch to the new branch on CLI" {
+    make_it
+
+    dolt sql -q 'call dolt_checkout("to_keep"); call dolt_branch("-m", "main", "master");'
+
+    dolt branch -av
+
+    run dolt status
+    [[ "$output" =~ "On branch master" ]] || false
+}
+
 @test "deleted-branches: can SQL connect with dolt_default_branch set to existing branch when checked out branch is deleted" {
     make_it
 
@@ -38,7 +67,7 @@ make_it() {
 
     server_query "dolt_repo_$$" 1 dolt "" "SET @@GLOBAL.dolt_repo_$$_default_branch = 'to_keep'" ""
 
-    server_query "dolt_repo_$$"  1 dolt "" 'delete from dolt_branches where name = "main"' ""
+    server_query "dolt_repo_$$"  1 dolt "" 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");' ""
 
     server_query "dolt_repo_$$" 1 dolt "" "SELECT * FROM test" "id\n" ""
 }
@@ -48,7 +77,7 @@ make_it() {
 
     start_sql_server "dolt_repo_$$"
 
-    server_query "dolt_repo_$$" 1 dolt "" 'delete from dolt_branches where name = "main"' ""
+    server_query "dolt_repo_$$" 1 dolt "" 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");' ""
 
     # Against the default branch it fails
     run server_query "dolt_repo_$$" 1 "" dolt "" "SELECT * FROM test" "id\n" ""
@@ -93,7 +122,7 @@ make_it() {
 
     start_sql_server "dolt_repo_$$"
 
-    server_query "dolt_repo_$$"  1 dolt "" 'delete from dolt_branches where name = "main"' ""
+    server_query "dolt_repo_$$"  1 dolt "" 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");' ""
 
     # We are able to use a database branch revision in the connection string
     server_query "dolt_repo_$$/to_keep" 1 dolt "" "SELECT * FROM test;"
@@ -111,7 +140,7 @@ make_it() {
 
     server_query "dolt_repo_$$" 1 dolt "" "SET @@GLOBAL.dolt_repo_$$_default_branch = 'to_keep'" ""
 
-    server_query "dolt_repo_$$"  1 dolt "" 'delete from dolt_branches where name = "main"' ""
+    server_query "dolt_repo_$$"  1 dolt "" 'call dolt_checkout("to_keep"); call dolt_branch("-D", "main");' ""
 
     server_query "dolt_repo_$$" 1 dolt "" "SELECT * FROM test" ""
     

integration-tests/bats/replication.bats

@@ -160,22 +160,6 @@ teardown() {
     [[ "$output" =~ "t1" ]] || false
 }
 
-@test "replication: push on branch table update" {
-    cd repo1
-    dolt config --local --add sqlserver.global.dolt_replicate_to_remote backup1
-    dolt sql -q "create table t1 (a int primary key)"
-    dolt add -A
-    dolt sql -q "UPDATE dolt_branches SET hash = COMMIT('--author', '{user_name} <{email_address}>','-m', 'cm') WHERE name = 'main' AND hash = @@repo1_head"
-
-    cd ..
-    dolt clone file://./bac1 repo2
-    cd repo2
-    run dolt ls
-    [ "$status" -eq 0 ]
-    [ "${#lines[@]}" -eq 2 ]
-    [[ "$output" =~ "t1" ]] || false
-}
-
 @test "replication: push on call dolt_branch(..." {
     cd repo1
     dolt config --local --add sqlserver.global.dolt_replicate_to_remote backup1

integration-tests/bats/sql-batch.bats

@@ -119,7 +119,6 @@ SQL
 
    dolt sql -b <<SQL
 SELECT dolt_reset('--hard');
-REPLACE INTO dolt_branches (hash,name) VALUES (@@test_head,'main');
 SQL
 
     run dolt status
@@ -129,7 +128,6 @@ SQL
     dolt sql -b <<SQL
 INSERT INTO test VALUES (1,1);
 SELECT dolt_reset('--hard');
-REPLACE INTO dolt_branches (hash,name) VALUES (@@test_head,'main');
 SQL
 
     run dolt status

integration-tests/bats/sql-server.bats

@@ -423,9 +423,7 @@ SQL
     [ "$status" -eq 0 ]
     [[ "$output" =~ "test" ]] || false
 
-    server_query repo1 1 dolt "" "
-        SELECT DOLT_RESET('--hard');
-        REPLACE INTO dolt_branches (name,hash) VALUES ('main', @@repo1_head);"
+    server_query repo1 1 dolt "" "SELECT DOLT_RESET('--hard');"
 
     run dolt status
     [ "$status" -eq 0 ]
@@ -436,8 +434,7 @@ SQL
 
     server_query repo1 1 dolt "" "
         INSERT INTO test VALUES (8,8);
-        SELECT DOLT_RESET('--hard');
-        REPLACE INTO dolt_branches (name,hash) VALUES ('main', @@repo1_head);"
+        SELECT DOLT_RESET('--hard');"
 
     run dolt status
     [ "$status" -eq 0 ]
@@ -777,7 +774,7 @@ SQL
     INSERT INTO one_pk (pk,c1,c2) VALUES (2,2,2),(3,3,3);
     CALL DOLT_ADD('.');
     SELECT commit('-am', 'test commit message', '--author', 'John Doe <john@example.com>');
-    INSERT INTO dolt_branches (name,hash) VALUES ('main', @@repo1_head);"
+    CALL DOLT_BRANCH('main', @@repo1_head);"
 
     server_query repo1 1 dolt "" "call dolt_add('.')" "status\n0"
     run dolt ls

integration-tests/bats/system-tables.bats

@@ -528,9 +528,18 @@ SQL
     [[ "$output" =~ "1" ]] || false
 }
 
-@test "system-tables: cannot delete last branch in dolt_branches" {
+@test "system-tables: dolt_branches is read-only" {
     run dolt sql -q "DELETE FROM dolt_branches"
     [ "$status" -ne 0 ]
+    [[ "$output" =~ "read-only" ]] || false
+
+    run dolt sql -q "INSERT INTO dolt_branches (name,hash) VALUES ('branch1', 'main');"
+    [ "$status" -ne 0 ]
+    [[ "$output" =~ "read-only" ]] || false
+
+    run dolt sql -q "UPDATE dolt_branches SET name = 'branch1' WHERE name = 'main'"
+    [ "$status" -ne 0 ]
+    [[ "$output" =~ "read-only" ]] || false
 }
 
 @test "system-tables: dolt diff includes changes from initial commit" {