allow dolt init on dolt repo with just config.json (#8838)

go/libraries/doltcore/env/config.go

@@ -145,8 +145,11 @@ func (dcc *DoltCliConfig) createLocalConfigAt(dir string, vals map[string]string
 	}
 
 	path := filepath.Join(dir, getLocalConfigPath())
-	cfg, err := config.NewFileConfig(path, dcc.fs, vals)
+	if exists, _ := dcc.fs.Exists(path); exists {
+		return nil
+	}
 
+	cfg, err := config.NewFileConfig(path, dcc.fs, vals)
 	if err != nil {
 		return err
 	}

go/libraries/doltcore/env/environment.go

@@ -499,7 +499,8 @@ func (dEnv *DoltEnv) createDirectories(dir string) (string, error) {
 		}
 
 		if len(entries) == 1 {
-			if !entries[0].IsDir() || entries[0].Name() != TmpDirName {
+			entry := entries[0]
+			if (entry.IsDir() && entry.Name() != TmpDirName) || (!entry.IsDir() && entry.Name() != configFile) {
 				return "", fmt.Errorf(".dolt directory already exists at '%s'", dir)
 			}
 		} else if len(entries) != 0 {

integration-tests/bats/init.bats

@@ -59,6 +59,28 @@ teardown() {
   assert_valid_repository
 }
 
+@test "init: explicit local configuration for config file" {
+  set_dolt_user "baz", "baz@bash.com"
+
+  mkdir .dolt
+
+  dolt config --add user.name foo
+  dolt config --add user.email foo@bar.com
+
+  run dolt config --local --get user.name
+  [ "$status" -eq 0 ]
+  [[ "$output" =~ "foo" ]] || false
+
+  run dolt config --local --get user.email
+  [ "$status" -eq 0 ]
+  [[ "$output" =~ "foo@bar.com" ]] || false
+
+  run dolt init
+  [ "$status" -eq 0 ]
+
+  assert_valid_repository
+}
+
 @test "init: explicit local configuration for name and email" {
   set_dolt_user "baz", "baz@bash.com"
 
@@ -263,7 +285,7 @@ teardown() {
 
     mkdir -p dbdir/.dolt
     cd dbdir
-    touch .dolt/config.json
+    touch .dolt/not_config.json
     run dolt init
     [ "$status" -eq 1 ]
     [[ "$output" =~ ".dolt directory already exists" ]] || false