diff --git a/services/webhook/sourcehut/builds_test.go b/services/webhook/sourcehut/builds_test.go
index 1a37279c99..0f1559fd0f 100644
--- a/services/webhook/sourcehut/builds_test.go
+++ b/services/webhook/sourcehut/builds_test.go
@@ -5,6 +5,7 @@ package sourcehut
 
 import (
 	"context"
+	"strings"
 	"testing"
 
 	webhook_model "code.gitea.io/gitea/models/webhook"
@@ -384,3 +385,83 @@ func TestSourcehutJSONPayload(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, "json test", body.Variables.Note)
 }
+
+func TestSourcehutAdjustManifest(t *testing.T) {
+	defer test.MockVariableValue(&setting.AppURL, "https://example.forgejo.org/")()
+	t.Run("without sources", func(t *testing.T) {
+		repo := &api.Repository{
+			CloneURL: "http://localhost:3000/testdata/repo.git",
+		}
+
+		manifest, err := adjustManifest(repo, "58771003157b81abc6bf41df0c5db4147a3e3c83", "refs/heads/main", strings.NewReader(`image: alpine/edge
+tasks:
+    - say-hello: |
+        echo hello
+    - say-world: echo world`), ".build.yml")
+
+		require.NoError(t, err)
+		assert.Equal(t, `sources:
+    - http://localhost:3000/testdata/repo.git#58771003157b81abc6bf41df0c5db4147a3e3c83
+environment:
+    BUILD_SUBMITTER: forgejo
+    BUILD_SUBMITTER_URL: https://example.forgejo.org/
+    GIT_REF: refs/heads/main
+image: alpine/edge
+tasks:
+    - say-hello: |
+        echo hello
+    - say-world: echo world
+`, string(manifest))
+	})
+
+	t.Run("with other sources", func(t *testing.T) {
+		repo := &api.Repository{
+			CloneURL: "http://localhost:3000/testdata/repo.git",
+		}
+
+		manifest, err := adjustManifest(repo, "58771003157b81abc6bf41df0c5db4147a3e3c83", "refs/heads/main", strings.NewReader(`image: alpine/edge
+sources:
+- http://other.example.conm/repo.git
+tasks:
+    - hello: echo world`), ".build.yml")
+
+		require.NoError(t, err)
+		assert.Equal(t, `sources:
+    - http://other.example.conm/repo.git
+    - http://localhost:3000/testdata/repo.git#58771003157b81abc6bf41df0c5db4147a3e3c83
+environment:
+    BUILD_SUBMITTER: forgejo
+    BUILD_SUBMITTER_URL: https://example.forgejo.org/
+    GIT_REF: refs/heads/main
+image: alpine/edge
+tasks:
+    - hello: echo world
+`, string(manifest))
+	})
+
+	t.Run("with same source", func(t *testing.T) {
+		repo := &api.Repository{
+			CloneURL: "http://localhost:3000/testdata/repo.git",
+		}
+
+		manifest, err := adjustManifest(repo, "58771003157b81abc6bf41df0c5db4147a3e3c83", "refs/heads/main", strings.NewReader(`image: alpine/edge
+sources:
+- http://localhost:3000/testdata/repo.git
+- http://other.example.conm/repo.git
+tasks:
+    - hello: echo world`), ".build.yml")
+
+		require.NoError(t, err)
+		assert.Equal(t, `sources:
+    - http://localhost:3000/testdata/repo.git#58771003157b81abc6bf41df0c5db4147a3e3c83
+    - http://other.example.conm/repo.git
+environment:
+    BUILD_SUBMITTER: forgejo
+    BUILD_SUBMITTER_URL: https://example.forgejo.org/
+    GIT_REF: refs/heads/main
+image: alpine/edge
+tasks:
+    - hello: echo world
+`, string(manifest))
+	})
+}