From 9d56b30c422684bdb2add13d8bf895313442c66b Mon Sep 17 00:00:00 2001
From: CrazyMax <1951866+crazy-max@users.noreply.github.com>
Date: Thu, 31 Jul 2025 10:02:44 +0200
Subject: [PATCH] bake: fix dockerfile default if empty

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>
---
 bake/bake.go      |  2 +-
 bake/bake_test.go | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/bake/bake.go b/bake/bake.go
index b0549b135..c2bb00254 100644
--- a/bake/bake.go
+++ b/bake/bake.go
@@ -676,7 +676,7 @@ func (c Config) ResolveTarget(name string, overrides map[string]map[string]Overr
 		s := "."
 		t.Context = &s
 	}
-	if t.Dockerfile == nil {
+	if t.Dockerfile == nil || (t.Dockerfile != nil && *t.Dockerfile == "") {
 		s := "Dockerfile"
 		t.Dockerfile = &s
 	}
diff --git a/bake/bake_test.go b/bake/bake_test.go
index bf7d3050b..526ca958f 100644
--- a/bake/bake_test.go
+++ b/bake/bake_test.go
@@ -2248,6 +2248,23 @@ target "app" {
 	require.Len(t, m["app"].Outputs, 0)
 }
 
+func TestEmptyDockerfile(t *testing.T) {
+	fp := File{
+		Name: "docker-bake.hcl",
+		Data: []byte(`
+target "app" {
+  dockerfile = ""
+}
+`),
+	}
+
+	ctx := context.TODO()
+	m, _, err := ReadTargets(ctx, []File{fp}, []string{"app"}, nil, nil, &EntitlementConf{})
+	require.NoError(t, err)
+	require.Contains(t, m, "app")
+	require.Equal(t, "Dockerfile", *m["app"].Dockerfile)
+}
+
 // https://github.com/docker/buildx/issues/2859
 func TestGroupTargetsWithDefault(t *testing.T) {
 	t.Run("OnTarget", func(t *testing.T) {