From 5def87764956c9e1d4b83bec135344cfbbd6c3e1 Mon Sep 17 00:00:00 2001
From: Marco Roth <marco.roth@intergga.ch>
Date: Wed, 5 Aug 2026 02:50:05 +0200
Subject: [PATCH 1/2] Action View: Add helpers from`importmap-rails` gem

---
 .../javascript_import_module_tag.yml          | 32 +++++++++++++++
 ...vascript_importmap_module_preload_tags.yml | 39 +++++++++++++++++++
 .../javascript_importmap_tags.yml             | 35 +++++++++++++++++
 .../javascript_inline_importmap_tag.yml       | 32 +++++++++++++++
 .../javascript_module_preload_tag.yml         | 35 +++++++++++++++++
 5 files changed, 173 insertions(+)
 create mode 100644 config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_import_module_tag.yml
 create mode 100644 config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_module_preload_tags.yml
 create mode 100644 config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_tags.yml
 create mode 100644 config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_inline_importmap_tag.yml
 create mode 100644 config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_module_preload_tag.yml

diff --git a/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_import_module_tag.yml b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_import_module_tag.yml
new file mode 100644
index 000000000..40d9a4535
--- /dev/null
+++ b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_import_module_tag.yml
@@ -0,0 +1,32 @@
+---
+name: "javascript_import_module_tag"
+source: "Importmap::ImportmapTagsHelper#javascript_import_module_tag"
+gem: "importmap-rails"
+output: "html"
+visibility: "public"
+supported: false
+supports_block: false
+signature: "javascript_import_module_tag(*module_names)"
+documentation_url: "https://www.rubydoc.info/gems/importmap-rails/Importmap/ImportmapTagsHelper#javascript_import_module_tag-instance_method"
+
+description: |-
+  Imports the named JavaScript module(s) using a `<script type="module">` tag. Each module name becomes an `import` statement in the body of the tag. Includes the Content Security Policy nonce when one is present.
+
+tag:
+  name: "script"
+  is_void: false
+  preferred: false
+  detect_style: "call_name"
+
+arguments:
+  - name: "module_names"
+    position: 1
+    type: "string"
+    optional: false
+    splat: true
+    description: |-
+      One or more module names to import.
+
+options: []
+block_arguments: []
+special_behaviors: []
diff --git a/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_module_preload_tags.yml b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_module_preload_tags.yml
new file mode 100644
index 000000000..7c8ef9d94
--- /dev/null
+++ b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_module_preload_tags.yml
@@ -0,0 +1,39 @@
+---
+name: "javascript_importmap_module_preload_tags"
+source: "Importmap::ImportmapTagsHelper#javascript_importmap_module_preload_tags"
+gem: "importmap-rails"
+output: "html"
+visibility: "public"
+supported: false
+supports_block: false
+signature: "javascript_importmap_module_preload_tags(importmap = Rails.application.importmap, entry_point: \"application\")"
+documentation_url: "https://www.rubydoc.info/gems/importmap-rails/Importmap/ImportmapTagsHelper#javascript_importmap_module_preload_tags-instance_method"
+
+description: |-
+  Returns `<link rel="modulepreload">` tags for all modules marked as `preload: true` in the `importmap` (defaults to `Rails.application.importmap`), such that they'll be fetched in advance by browsers supporting this link type.
+
+tag:
+  name: "link"
+  is_void: true
+  preferred: false
+  detect_style: "call_name"
+
+arguments:
+  - name: "importmap"
+    position: 1
+    type: "object"
+    optional: true
+    default: "Rails.application.importmap"
+    description: |-
+      The `Importmap::Map` whose preloaded modules should be linked.
+
+options:
+  - name: "entry_point"
+    type: "string"
+    description: |-
+      Entry point used to resolve the preloaded module packages. Defaults to `"application"`.
+
+block_arguments: []
+
+special_behaviors:
+  - "produces_multiple_elements"
diff --git a/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_tags.yml b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_tags.yml
new file mode 100644
index 000000000..5544fcbbe
--- /dev/null
+++ b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_importmap_tags.yml
@@ -0,0 +1,35 @@
+---
+name: "javascript_importmap_tags"
+source: "Importmap::ImportmapTagsHelper#javascript_importmap_tags"
+gem: "importmap-rails"
+output: "html"
+visibility: "public"
+supported: false
+supports_block: false
+signature: "javascript_importmap_tags(entry_point = \"application\", importmap: Rails.application.importmap)"
+documentation_url: "https://www.rubydoc.info/gems/importmap-rails/Importmap/ImportmapTagsHelper#javascript_importmap_tags-instance_method"
+
+description: |-
+  Sets up all `<script>` tags needed to use an importmap-powered entrypoint, which defaults to `application`. Renders the inline importmap `<script>`, the `modulepreload` `<link>` tags for all preloaded modules, and the module import `<script>`.
+
+tag: null
+
+arguments:
+  - name: "entry_point"
+    position: 1
+    type: "string"
+    optional: true
+    default: "\"application\""
+    description: |-
+      Name of the JavaScript module to import as the entry point.
+
+options:
+  - name: "importmap"
+    type: "object"
+    description: |-
+      The `Importmap::Map` to render. Defaults to `Rails.application.importmap`.
+
+block_arguments: []
+
+special_behaviors:
+  - "produces_multiple_elements"
diff --git a/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_inline_importmap_tag.yml b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_inline_importmap_tag.yml
new file mode 100644
index 000000000..e9164e15b
--- /dev/null
+++ b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_inline_importmap_tag.yml
@@ -0,0 +1,32 @@
+---
+name: "javascript_inline_importmap_tag"
+source: "Importmap::ImportmapTagsHelper#javascript_inline_importmap_tag"
+gem: "importmap-rails"
+output: "html"
+visibility: "public"
+supported: false
+supports_block: false
+signature: "javascript_inline_importmap_tag(importmap_json = Rails.application.importmap.to_json(resolver: self))"
+documentation_url: "https://www.rubydoc.info/gems/importmap-rails/Importmap/ImportmapTagsHelper#javascript_inline_importmap_tag-instance_method"
+
+description: |-
+  Generates an inline importmap `<script type="importmap">` tag using the passed `importmap_json` JSON string. Defaults to `Rails.application.importmap.to_json(resolver: self)`. Includes `data-turbo-track="reload"` and the Content Security Policy nonce when one is present.
+
+tag:
+  name: "script"
+  is_void: false
+  preferred: false
+  detect_style: "call_name"
+
+arguments:
+  - name: "importmap_json"
+    position: 1
+    type: "string"
+    optional: true
+    default: "Rails.application.importmap.to_json(resolver: self)"
+    description: |-
+      JSON string of the importmap to inline.
+
+options: []
+block_arguments: []
+special_behaviors: []
diff --git a/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_module_preload_tag.yml b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_module_preload_tag.yml
new file mode 100644
index 000000000..508e33145
--- /dev/null
+++ b/config/action_view_helpers/importmap-rails/importmap_tags_helper/javascript_module_preload_tag.yml
@@ -0,0 +1,35 @@
+---
+name: "javascript_module_preload_tag"
+source: "Importmap::ImportmapTagsHelper#javascript_module_preload_tag"
+gem: "importmap-rails"
+output: "html"
+visibility: "public"
+supported: false
+supports_block: false
+signature: "javascript_module_preload_tag(*paths)"
+documentation_url: "https://www.rubydoc.info/gems/importmap-rails/Importmap/ImportmapTagsHelper#javascript_module_preload_tag-instance_method"
+
+description: |-
+  Returns a `<link rel="modulepreload">` tag for the JavaScript module residing in each of `*paths`. Returns one link tag per path element.
+
+tag:
+  name: "link"
+  is_void: true
+  preferred: false
+  detect_style: "call_name"
+
+arguments:
+  - name: "paths"
+    position: 1
+    type: "string"
+    optional: false
+    splat: true
+    description: |-
+      One or more module paths to preload.
+
+options: []
+block_arguments: []
+
+special_behaviors:
+  - type: "multiple_elements"
+    source: "splat_args"

From 7db7428f1c19e54dcc0d9da5a038cd4622d6b6ff Mon Sep 17 00:00:00 2001
From: Marco Roth <marco.roth@intergga.ch>
Date: Wed, 5 Aug 2026 03:01:23 +0200
Subject: [PATCH 2/2] Update signatures

---
 sig/herb/action_view/helper_registry.rbs | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/sig/herb/action_view/helper_registry.rbs b/sig/herb/action_view/helper_registry.rbs
index 396498266..92e49780c 100644
--- a/sig/herb/action_view/helper_registry.rbs
+++ b/sig/herb/action_view/helper_registry.rbs
@@ -459,6 +459,16 @@ module Herb
 
       URL_FOR: ::Symbol
 
+      JAVASCRIPT_IMPORT_MODULE_TAG: ::Symbol
+
+      JAVASCRIPT_IMPORTMAP_MODULE_PRELOAD_TAGS: ::Symbol
+
+      JAVASCRIPT_IMPORTMAP_TAGS: ::Symbol
+
+      JAVASCRIPT_INLINE_IMPORTMAP_TAG: ::Symbol
+
+      JAVASCRIPT_MODULE_PRELOAD_TAG: ::Symbol
+
       TURBO_EXEMPTS_PAGE_FROM_CACHE: ::Symbol
 
       TURBO_EXEMPTS_PAGE_FROM_CACHE_TAG: ::Symbol
@@ -1083,6 +1093,16 @@ module Herb
 
       URL_FOR: HelperEntry
 
+      JAVASCRIPT_IMPORT_MODULE_TAG: HelperEntry
+
+      JAVASCRIPT_IMPORTMAP_MODULE_PRELOAD_TAGS: HelperEntry
+
+      JAVASCRIPT_IMPORTMAP_TAGS: HelperEntry
+
+      JAVASCRIPT_INLINE_IMPORTMAP_TAG: HelperEntry
+
+      JAVASCRIPT_MODULE_PRELOAD_TAG: HelperEntry
+
       TURBO_EXEMPTS_PAGE_FROM_CACHE: HelperEntry
 
       TURBO_EXEMPTS_PAGE_FROM_CACHE_TAG: HelperEntry