From b2a3715a8b045d7bdc2d97db08716177ba61ee21 Mon Sep 17 00:00:00 2001
From: Gaetan Craig-Riou <gaetan.riou@gmail.com>
Date: Wed, 16 Jul 2025 13:05:20 +1000
Subject: [PATCH] Fix bug

Don't add a leading coma when the tag list is empty
---
 .../tag_list_input_controller.js                      |  8 ++++++--
 .../stimulus/tag_list_input_controller_test.js        | 11 +++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/app/components/tag_list_input_component/tag_list_input_controller.js b/app/components/tag_list_input_component/tag_list_input_controller.js
index 5fb0795e59..2ded4bb5a7 100644
--- a/app/components/tag_list_input_component/tag_list_input_controller.js
+++ b/app/components/tag_list_input_component/tag_list_input_controller.js
@@ -22,7 +22,11 @@ export default class extends Controller {
     }
 
     // add to tagList
-    this.tagListTarget.value = this.tagListTarget.value.concat(`,${newTagName}`);
+    if (this.tagListTarget.value == "") {
+      this.tagListTarget.value = newTagName;
+    } else {
+      this.tagListTarget.value = this.tagListTarget.value.concat(`,${newTagName}`);
+    }
 
     // Create new li component with value
     const newTagElement = this.templateTarget.content.cloneNode(true);
@@ -40,7 +44,7 @@ export default class extends Controller {
 
     // Remove tag from list
     const tags = this.tagListTarget.value.split(",");
-    this.tagListTarget.value = tags.filter(tag => tag != tagName).join(",");
+    this.tagListTarget.value = tags.filter((tag) => tag != tagName).join(",");
 
     // manualy dispatch an Input event so the change gets picked up by the bulk form controller
     this.tagListTarget.dispatchEvent(new InputEvent("input"));
diff --git a/spec/javascripts/stimulus/tag_list_input_controller_test.js b/spec/javascripts/stimulus/tag_list_input_controller_test.js
index 7df91dd750..00385a6623 100644
--- a/spec/javascripts/stimulus/tag_list_input_controller_test.js
+++ b/spec/javascripts/stimulus/tag_list_input_controller_test.js
@@ -126,6 +126,17 @@ describe("TagListInputController", () => {
         expect(variant_add_tag.classList).toContain("tag-error");
       });
     });
+
+    describe("when no tag yet", () => {
+      it("doesn't include leading comma in hidden tag list input", () => {
+        variant_tag_list.value = "";
+
+        variant_add_tag.value = "latest";
+        variant_add_tag.dispatchEvent(new KeyboardEvent("keydown", { key: "Enter" }));
+
+        expect(variant_tag_list.value).toBe("latest");
+      });
+    });
   });
 
   describe("removeTag", () => {