Decouple extension UI layout from folder structure

.gitignore

@@ -26,6 +26,7 @@ extensions/*
 **/packages
 **/dev/**/bin
 **/dev/pyRevitLabs/TestResults/
+**/*_wpftmp.csproj
 
 # ignore sphinx build files
 docs/_*

dev/pyRevitLabs/pyRevitLabs.PyRevit/PyRevitConsts.cs

@@ -183,6 +183,10 @@ public static class PyRevitConsts {
         public const string ConfigsNewLoaderKey = "new_loader";
         public const bool ConfigsNewLoaderDefault = true;
 
+        // layout settings
+        public const string ConfigsDisableCustomLayoutsKey = "disable_custom_layouts";
+        public const bool ConfigsDisableCustomLayoutsDefault = false;
+
         // theme
         public static SolidColorBrush PyRevitAccentBrush = new SolidColorBrush(Color.FromArgb(0xFF, 0xf3, 0x9c, 0x12));
         public static SolidColorBrush PyRevitBackgroundBrush = new SolidColorBrush(Color.FromArgb(0xFF, 0x2c, 0x3e, 0x50));

dev/pyRevitLoader/pyRevitExtensionParser/ParsedExtension.cs

@@ -30,6 +30,14 @@ public class ParsedExtension : ParsedComponent
         /// </summary>
         public List<ExternalLayoutDirective> ExternalLayoutDirectives { get; set; } = new List<ExternalLayoutDirective>();
 
+        /// <summary>
+        /// Tools from the tool index that are NOT referenced in the layout YAML.
+        /// These are included in assembly generation but NOT shown in the ribbon UI.
+        /// This ensures all tools have compiled command types available, so adding
+        /// a tool to the layout later doesn't require a new assembly build.
+        /// </summary>
+        public List<ParsedComponent> AssemblyOnlyComponents { get; set; }
+
         /// <summary>
         /// Gets or sets the list of users authorized to access this extension.
         /// When populated, only users in this list can use the extension.
@@ -76,6 +84,7 @@ private bool DirExists(string path)
 
         private static readonly HashSet<string> _hashDirSuffixes = new HashSet<string>(StringComparer.OrdinalIgnoreCase)
         {
+            ".extension",
             ".tab",
             ".panel",
             ".pulldown",
@@ -93,7 +102,8 @@ private bool DirExists(string path)
         private static readonly HashSet<string> _hashDirNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase)
         {
             "lib",
-            "hooks"
+            "hooks",
+            "tools"
         };
 
         /// <summary>
@@ -265,6 +275,8 @@ public string StartupScript
         /// <summary>
         /// Collects all command components from this extension (cached after first call).
         /// Builds control IDs for each component based on hierarchy.
+        /// Also includes assembly-only components (tools not in the layout but still
+        /// compiled into the DLL so they're available if the layout changes).
         /// </summary>
         public IEnumerable<ParsedComponent> CollectCommandComponents()
         {
@@ -273,6 +285,14 @@ public IEnumerable<ParsedComponent> CollectCommandComponents()
                 _cachedCommandComponents = new List<ParsedComponent>();
                 // Start with no parent control ID - tabs will be the first level
                 CollectInto(_cachedCommandComponents, this.Children, null);
+
+                // Include tools that exist on disk but aren't referenced in the layout.
+                // They won't appear in the ribbon, but their command types will be
+                // compiled into the assembly so layout changes don't require a rebuild.
+                if (AssemblyOnlyComponents != null)
+                {
+                    CollectInto(_cachedCommandComponents, AssemblyOnlyComponents, null);
+                }
             }
             return _cachedCommandComponents;
         }

dev/pyRevitLoader/pyRevitExtensionParser/PyRevitConfig.cs

@@ -84,6 +84,23 @@ public string UserLocale
             }
         }
 
+        /// <summary>
+        /// Gets whether custom layouts are globally disabled.
+        /// When true, GetCustomLayoutPath always returns null (bundled layouts still apply).
+        /// </summary>
+        public bool DisableCustomLayouts
+        {
+            get
+            {
+                var value = _ini.IniReadValue("core", "disable_custom_layouts");
+                return TryParseConfigBool(value, out var result) && result;
+            }
+            set
+            {
+                _ini.IniWriteValue("core", "disable_custom_layouts", value ? TrueString : FalseString);
+            }
+        }
+
         /// <summary>
         /// Gets or sets whether the new loader architecture is enabled.
         /// </summary>
@@ -607,6 +624,53 @@ public ExtensionConfig ParseExtensionByName(string extensionName)
             return null; // Return null if the extension is not found
         }
 
+        /// <summary>
+        /// Gets the custom layout file path for an extension, if configured.
+        /// </summary>
+        /// <param name="extensionName">Extension name (without .extension suffix)</param>
+        /// <returns>Path to custom layout file, or null if not configured or file doesn't exist</returns>
+        public string GetCustomLayoutPath(string extensionName)
+        {
+            if (string.IsNullOrEmpty(extensionName))
+                return null;
+
+            // Global toggle: skip custom layouts when disabled
+            if (DisableCustomLayouts)
+                return null;
+
+            var section = $"{extensionName}.extension";
+            var value = _ini.IniReadValue(section, "custom_layout_path");
+
+            if (string.IsNullOrEmpty(value))
+                return null;
+
+            value = value.Trim();
+            // Strip quotes if present
+            if (value.Length >= 2 &&
+                ((value[0] == '"' && value[value.Length - 1] == '"') ||
+                 (value[0] == '\'' && value[value.Length - 1] == '\'')))
+            {
+                value = value.Substring(1, value.Length - 2).Trim();
+            }
+
+            // Only return if file exists
+            return File.Exists(value) ? value : null;
+        }
+
+        /// <summary>
+        /// Sets or clears the custom layout file path for an extension.
+        /// </summary>
+        /// <param name="extensionName">Extension name (without .extension suffix)</param>
+        /// <param name="layoutPath">Path to custom layout file, or null/empty to clear</param>
+        public void SetCustomLayoutPath(string extensionName, string layoutPath)
+        {
+            if (string.IsNullOrEmpty(extensionName))
+                return;
+
+            var section = $"{extensionName}.extension";
+            _ini.IniWriteValue(section, "custom_layout_path", layoutPath ?? string.Empty);
+        }
+
         /// <summary>
         /// Parses booleans from INI values (matches Python/json-style and common variants).
         /// </summary>

dev/pyRevitLoader/pyRevitExtensionParser/pyRevitExtensionParser.csproj

@@ -35,6 +35,7 @@
       <Compile Include="ParserLogger.cs" />
       <Compile Include="PyRevitConfig.cs" />
       <Compile Include="ExtensionParser.cs" />
+      <Compile Include="LayoutParser.cs" />
       <Compile Include="IniFile.cs" />
     </ItemGroup>
 

extensions/pyRevitCore.extension/extension_layout.yaml

@@ -0,0 +1,27 @@
+tabs:
+  - name: pyRevit
+    panels:
+      - name: pyRevit
+        layout:
+          - stack:
+              - Search
+              - Spy
+              - Reload
+          - '>>>'
+          - About
+          - Update
+          - Extensions
+          - stack:
+              - Wiki
+              - Blog
+              - Repo
+          - stack:
+              - apidocs
+              - emojis
+              - rpw Docs
+          - stack:
+              - Icons8
+              - RegEx Tool
+              - Report Bugs
+          - Settings
+          - Layout Builder

extensions/pyRevitCore.extension/layouts/simple.layout.yaml

@@ -0,0 +1,14 @@
+tabs:
+- name: pyRevit
+  panels:
+  - name: pyRevit
+    layout:
+    - Search
+    - '>>>'
+    - stack:
+      - About
+      - Update
+      - Extensions
+    - Settings
+    - Layout Builder
+