Merge pull request #6346 from dolthub/macneale4/empty-db-panic

Allow empty databases in the shell prompt

go/cmd/dolt/commands/sql.go

@@ -811,7 +811,6 @@ func execShell(sqlCtx *sql.Context, qryist cli.Queryist, format engine.PrintResu
 // getDBFromSession returns the current database name for the session, handling all the errors along the way by printing
 // red error messages to the CLI. If there was an issue getting the db name, the second return value is false.
 func getDBFromSession(sqlCtx *sql.Context, qryist cli.Queryist) (db string, ok bool) {
-	db = "unknown"
 	_, resp, err := qryist.Query(sqlCtx, "select database()")
 	if err != nil {
 		cli.Println(color.RedString("Failure to get DB Name for session" + err.Error()))
@@ -827,11 +826,11 @@ func getDBFromSession(sqlCtx *sql.Context, qryist cli.Queryist) (db string, ok b
 		cli.Println(color.RedString("Failure to get DB Name for session" + err.Error()))
 		return db, false
 	}
-	if row[0] == nil || row[0].(string) == "" {
-		cli.Println(color.RedString("Empty Database name obtained" + err.Error()))
-		return db, false
+	if row[0] == nil {
+		db = ""
+	} else {
+		db = row[0].(string)
 	}
-	db = row[0].(string)
 	return db, true
 }
 

integration-tests/bats/sql-shell-empty-prompt.expect

@@ -0,0 +1,32 @@
+#!/usr/bin/expect -f
+
+set timeout 5
+spawn dolt sql
+
+expect {
+    "> " { send "select 23;\r"; }
+    timeout { exit 1; }
+}
+
+expect {
+    "| 23 |" { }
+    timeout { exit 1; }
+}
+expect {
+    "| 23 |" { }
+    timeout { exit 1; }
+}
+
+expect {
+    "> " { send "exit;\r"; }
+    timeout { exit 1; }
+}
+
+expect {
+   eof { }
+   timeout { exit 1; }
+}
+
+set waitval [wait -i $spawn_id]
+set exval [lindex $waitval 3]
+exit $exval

integration-tests/bats/sql-shell.bats

@@ -71,6 +71,18 @@ teardown() {
     $BATS_TEST_DIRNAME/sql-works-after-failing-query.expect
 }
 
+@test "sql-shell: empty DB in prompt is OK" {
+    skiponwindows "Need to install expect and make this script work on windows."
+    if [ "$SQL_ENGINE" = "remote-engine" ]; then
+      skip "Presently sql command will not connect to remote server due to lack of lock file where there are not DBs."
+    fi
+    # ignore common setup. Use an empty db with no server.
+    rm -rf .dolt
+    mkdir emptyDb
+    cd emptyDb
+    $BATS_TEST_DIRNAME/sql-shell-empty-prompt.expect
+}
+
 @test "sql-shell: delimiter" {
     skiponwindows "Need to install expect and make this script work on windows."
     mkdir doltsql

integration-tests/bats/sql-works-after-failing-query.expect

@@ -1,4 +1,4 @@
-#!/usr/bin/expect
+#!/usr/bin/expect -f
 
 set timeout 1
 spawn dolt sql
@@ -15,3 +15,4 @@ expect {
   "pid 0 is already in use" { exit 1 }
   " 1 " { exit 0 }
 }
+