diff --git a/internal/formatter/formatter.go b/internal/formatter/formatter.go
index f7df66c..15cbf96 100644
--- a/internal/formatter/formatter.go
+++ b/internal/formatter/formatter.go
@@ -64,6 +64,9 @@ func (e *formatEnvironment) indentLevelUp() {
 
 func (e *formatEnvironment) indentLevelDown() {
 	e.indentLevel--
+	if e.indentLevel < 0 {
+		e.indentLevel = 0
+	}
 }
 
 func (e *formatEnvironment) genIndent() []ast.Node {
@@ -242,6 +245,7 @@ func formatItem(node ast.Node, env *formatEnvironment) ast.Node {
 	}
 	if commentAfterMatcher.IsMatch(node) {
 		results = append(results, linebreakNode)
+		env.indentLevelDown()
 	}
 
 	breakStatementAfterMatcher := astutil.NodeMatcher{
@@ -251,7 +255,7 @@ func formatItem(node ast.Node, env *formatEnvironment) ast.Node {
 	}
 	if breakStatementAfterMatcher.IsMatch(node) {
 		results = append(results, linebreakNode)
-		env.indentLevelDown()
+		env.indentLevelReset()
 	}
 
 	return &ast.ItemWith{Toks: results}
diff --git a/internal/formatter/formatter_test.go b/internal/formatter/formatter_test.go
index 38ff936..997eb55 100644
--- a/internal/formatter/formatter_test.go
+++ b/internal/formatter/formatter_test.go
@@ -1,6 +1,11 @@
 package formatter
 
 import (
+	"os"
+	"path/filepath"
+	"runtime"
+	"slices"
+	"strings"
 	"testing"
 
 	"github.com/sqls-server/sqls/ast"
@@ -20,7 +25,7 @@ func TestEval(t *testing.T) {
 		{
 			name:     "InsertIntoFormat",
 			input:    "INSERT INTO users (NAME, email) VALUES ('john doe', 'example@host.com')",
-			expected: "INSERT INTO users(\n\tNAME,\n\temail\n)\nVALUES(\n'john doe',\n'example@host.com'\n)",
+			expected: "INSERT INTO users(\n\tNAME,\n\temail\n)\nVALUES(\n\t'john doe',\n\t'example@host.com'\n)",
 			params:   lsp.DocumentFormattingParams{},
 			config: &config.Config{
 				LowercaseKeywords: false,
@@ -117,3 +122,51 @@ func parseInit(t *testing.T, input string) []*ast.Statement {
 	}
 	return stmts
 }
+
+func TestFormat(t *testing.T) {
+	_, filename, _, _ := runtime.Caller(0)
+	dir := filepath.Dir(filename)
+
+	files, err := filepath.Glob(filepath.Join(dir, "testdata", "*.sql"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	slices.Sort(files)
+
+	opts := &ast.RenderOptions{
+		LowerCase:        false,
+		IdentifierQuoted: false,
+	}
+	env := &formatEnvironment{}
+	for _, fname := range files {
+		b, err := os.ReadFile(fname)
+		if err != nil {
+			t.Fatal(err)
+		}
+		parsed, err := parser.Parse(string(b))
+		if err != nil {
+			t.Fatal(err)
+		}
+		formatted := Eval(parsed, env)
+		got := strings.TrimRight(formatted.Render(opts), "\n") + "\n"
+
+		b, err = os.ReadFile(fname[:len(fname)-4] + ".golden")
+		if err != nil {
+			t.Fatal(err)
+		}
+		want := string(b)
+		if got != want {
+			if _, err := os.Stat(fname[:len(fname)-4] + ".ignore"); err != nil {
+				t.Logf("%s:\n"+
+					"    want: %q\n"+
+					"     got: %q\n",
+					fname, want, got)
+			} else {
+				t.Errorf("%s:\n"+
+					"    want: %q\n"+
+					"     got: %q\n",
+					fname, want, got)
+			}
+		}
+	}
+}
diff --git a/internal/formatter/testdata/001.golden b/internal/formatter/testdata/001.golden
new file mode 100644
index 0000000..bac5b43
--- /dev/null
+++ b/internal/formatter/testdata/001.golden
@@ -0,0 +1,4 @@
+SELECT
+	*
+FROM
+	TABLE
diff --git a/internal/formatter/testdata/001.sql b/internal/formatter/testdata/001.sql
new file mode 100644
index 0000000..84b380f
--- /dev/null
+++ b/internal/formatter/testdata/001.sql
@@ -0,0 +1 @@
+select * From table
diff --git a/internal/formatter/testdata/002.golden b/internal/formatter/testdata/002.golden
new file mode 100644
index 0000000..5a60070
--- /dev/null
+++ b/internal/formatter/testdata/002.golden
@@ -0,0 +1,13 @@
+-- hoge --
+SELECT
+	x/*x*/,
+	/*x*/y
+FROM
+	zzz;
+-- zzzz
+SELECT
+	*
+FROM
+	yyy;
+-- yyyy
+-- hage --
diff --git a/internal/formatter/testdata/002.sql b/internal/formatter/testdata/002.sql
new file mode 100644
index 0000000..2106699
--- /dev/null
+++ b/internal/formatter/testdata/002.sql
@@ -0,0 +1,4 @@
+ -- hoge --
+SELECT x/*x*/, /*x*/y FROM zzz; -- zzzz
+SELECT * FROM yyy; -- yyyy
+            -- hage --
diff --git a/internal/formatter/testdata/003.golden b/internal/formatter/testdata/003.golden
new file mode 100644
index 0000000..b09ee57
--- /dev/null
+++ b/internal/formatter/testdata/003.golden
@@ -0,0 +1,28 @@
+-- hoge --
+SELECT
+		x/*x*/,
+		/*x*/y
+	FROM
+		zzz;
+-- zzzz
+SELECT
+		*
+	FROM
+		yyy;
+-- yyyy
+-- hage --
+SELECT
+    ap.autograph_purchase_id AS "id",
+    ap.order_number AS "order",
+    ap.product_price AS "productPrice",
+    i.name AS "influencerName",
+    p.name AS "productName",
+    u.email AS "email"
+FROM
+    autograph_purchaseASap innser
+JOIN influencer AS i
+    ON autograph_purchase.influencer_id = influencer.influencer_id
+LEFT JOIN product AS p
+    ON product.product_id = autograph_purchase.product_id
+LEFT JOIN USER AS u
+    ON USER.user_id = autograph_purchase.user_id
diff --git a/internal/formatter/testdata/003.ignroe b/internal/formatter/testdata/003.ignroe
new file mode 100644
index 0000000..e69de29
diff --git a/internal/formatter/testdata/003.sql b/internal/formatter/testdata/003.sql
new file mode 100644
index 0000000..540808c
--- /dev/null
+++ b/internal/formatter/testdata/003.sql
@@ -0,0 +1,15 @@
+SELECT
+    ap.autograph_purchase_id AS "id",
+    ap.order_number AS "order",
+    ap.product_price AS "productPrice",
+    i.name AS "influencerName",
+    p.name AS "productName",
+    u.email AS "email"
+FROM
+    autograph_purchaseASap innser
+JOIN influencer AS i
+    ON autograph_purchase.influencer_id = influencer.influencer_id
+LEFT JOIN product AS p
+    ON product.product_id = autograph_purchase.product_id
+LEFT JOIN USER1 AS u
+    ON USER1.user_id = autograph_purchase.user_id