fix(decorators): patch container-responsive styles to fix stale container queries and add customElement wrapper that sets .is and warns on class/tag mismatch

changelog.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## 2026-03-11 - 2.2.2 - fix(decorators)
+patch container-responsive styles to fix stale container queries and add customElement wrapper that sets .is and warns on class/tag mismatch
+
+- containerResponsive now derives the kebab name and replaces stale '@container <derived>' occurrences inside CSSResult cssText using unsafeCSS to correct container queries produced before decorators ran
+- containerResponsive appends containerContextStyles to the component styles while preserving/processing existing static styles
+- Added a customElement decorator wrapper that assigns .is on the class, logs a warning if the class name kebab-cases to a different tag name, and delegates to Lit's customElement
+- ts/index.ts now re-exports customElement from the local decorator so the new behavior is used project-wide
+
 ## 2026-03-11 - 2.2.1 - fix(dees-element)
 rename cssForCustom to cssForConstraint, remove DeesElement static cssFor* helpers, and add optional elementClass parameter to cssManager breakpoint helpers
 

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@design.estate/dees-element',
-  version: '2.2.1',
+  version: '2.2.2',
   description: 'A library for creating custom elements extending the lit element class with additional functionalities.'
 }

ts/decorators.containerresponsive.ts

@@ -1,19 +1,47 @@
+import { unsafeCSS, type CSSResult } from 'lit';
 import * as domtools from '@design.estate/dees-domtools';
 
+const camelToKebab = (name: string) =>
+  name.replace(/([a-z])([A-Z])/g, '$1-$2').toLowerCase();
+
 export function containerResponsive() {
   return function (target: any) {
     const tagName: string =
       target.is || target.name.replace(/([a-z])([A-Z])/g, '$1-$2').toLowerCase();
-    const containerStyles = domtools.breakpoints.containerContextStyles(tagName);
 
-    const original = target.styles;
+    // If .is differs from the regex-derived name, cssManager.cssFor*(css, this)
-    if (Array.isArray(original)) {
+    // in static styles (evaluated before decorators) used the wrong container name.
-      target.styles = [...original, containerStyles];
+    // Fix those stale references now.
-    } else if (original) {
+    const derivedName = target.name ? camelToKebab(target.name) : null;
-      target.styles = [original, containerStyles];
+    if (derivedName && derivedName !== tagName) {
+      const fixStyle = (style: CSSResult) => {
+        if (style && style.cssText && style.cssText.includes(`@container ${derivedName}`)) {
+          return unsafeCSS(
+            style.cssText.replaceAll(`@container ${derivedName}`, `@container ${tagName}`)
+          );
+        }
+        return style;
+      };
+
+      const original = target.styles;
+      if (Array.isArray(original)) {
+        target.styles = original.map(fixStyle);
+      } else if (original) {
+        target.styles = fixStyle(original);
+      }
+    }
+
+    // Append containment context styles
+    const containerStyles = domtools.breakpoints.containerContextStyles(tagName);
+    const current = target.styles;
+    if (Array.isArray(current)) {
+      target.styles = [...current, containerStyles];
+    } else if (current) {
+      target.styles = [current, containerStyles];
     } else {
       target.styles = [containerStyles];
     }
+
     return target;
   };
 }

ts/decorators.customelement.ts

@@ -0,0 +1,25 @@
+import { customElement as litCustomElement } from 'lit/decorators/custom-element.js';
+
+const camelToKebab = (name: string) =>
+  name.replace(/([a-z])([A-Z])/g, '$1-$2').toLowerCase();
+
+export function customElement(tagName: string) {
+  return (classOrTarget: any, context?: any) => {
+    // Set .is so that other decorators and utilities can read the tag name
+    classOrTarget.is = tagName;
+
+    // Warn if class name convention doesn't match the tag
+    if (classOrTarget.name) {
+      const derived = camelToKebab(classOrTarget.name);
+      if (derived !== tagName) {
+        console.warn(
+          `[dees-element] Class "${classOrTarget.name}" kebab-cases to "${derived}" but tag is "${tagName}". ` +
+          `Container queries use .is ("${tagName}").`
+        );
+      }
+    }
+
+    // Delegate to Lit's original decorator
+    return litCustomElement(tagName)(classOrTarget, context);
+  };
+}

ts/index.ts

@@ -7,7 +7,7 @@ export { html as static, unsafeStatic } from 'lit/static-html.js';
 
 export { unsafeHTML } from 'lit/directives/unsafe-html.js';
 
-export { customElement } from 'lit/decorators/custom-element.js';
+export { customElement } from './decorators.customelement.js';
 
 export { property, state, query, queryAll, queryAsync } from 'lit/decorators.js';