Fix tp-name property being incorrectly set for layer names in string form

When calling (tp-set str 'layer-name), the layer name symbol was wrapped
in a list by tp--parse-args. tp--resolve-props then incorrectly treated
this single-element list as a plist and generated an anonymous tp-anon-X
name instead of using the actual layer name.

The fix adds detection in tp--resolve-props for single-element lists
containing a defined layer/group name symbol, and correctly resolves
them by recursing with just the symbol.

Co-authored-by: Kinneyzhang <38454496+Kinneyzhang@users.noreply.github.com>

tp-tests.el

@@ -2070,6 +2070,21 @@ Returns list of (START END VALUE) intervals."
     ;; tp-name should be preserved for reactive text property support
     (should (eq (get-text-property 0 'tp-name str) 'my-style))))
 
+(ert-deftest tp-test-set-entire-string-with-layer-name ()
+  "Test tp-set with layer name on entire string (string form).
+This tests the fix for the bug where (tp-set str 'layer-name) would
+incorrectly generate an anonymous tp-name instead of using the layer name."
+  (tp-test-with-temp-buffer
+    ;; Define a layer with reactive variables
+    (tp-define-layer my-entire-string-layer
+      :props (face (:background $my-entire-string-color))
+      :data ((my-entire-string-color . "blue")))
+    (let ((str (tp-set " " 'my-entire-string-layer)))
+      ;; tp-name should be the defined layer name, not an anonymous tp-anon-X
+      (should (eq (get-text-property 0 'tp-name str) 'my-entire-string-layer))
+      ;; face should be correctly set
+      (should (equal (plist-get (get-text-property 0 'face str) :background) "blue")))))
+
 (ert-deftest tp-test-reset-with-layer-name ()
   "Test tp-reset accepts a layer name defined by define-tp."
   (tp-test-with-temp-buffer

tp.el

@@ -2337,6 +2337,7 @@ Appends 'tp-name property to identify the layer."
   "Resolve PROPS to a property list with layer metadata.
 PROPS can be:
 - A symbol (layer name from `tp-layer-alist' or group name from `tp-layer-groups')
+- A single-element list containing a layer/group symbol (from string form of tp-set)
 - A plist (handles anonymous layers with reactive variables)
 
 If PROPS is a symbol:
@@ -2356,6 +2357,17 @@ For group names, includes `tp-layers' property with the full layer stack."
   (cond
    ;; Already a plist - check for reactive variables and add tp-name
    ((listp props)
+    ;; Handle single-element list containing a layer/group name symbol.
+    ;; This can happen when tp-set is called with string form: (tp-set str 'layer-name)
+    ;; which produces props = (layer-name) in tp--parse-args.
+    (let ((first-elem (car-safe props)))
+      (if (and (= (length props) 1)
+               (symbolp first-elem)
+               (or (assoc first-elem tp-layer-alist)
+                   (assoc first-elem tp-layer-groups)))
+          ;; It's a layer/group name wrapped in a list - recurse with the symbol
+          (tp--resolve-props first-elem)
+        ;; Normal plist processing
         (let* ((existing-tp-name (plist-get props 'tp-name))
                (reactive-syms (tp--collect-reactive-symbols props)))
           (if reactive-syms
@@ -2373,7 +2385,7 @@ For group names, includes `tp-layers' property with the full layer stack."
             (if existing-tp-name
                 props
               (let ((layer-name (tp--generate-anonymous-layer-name)))
-            (append props (list 'tp-name layer-name)))))))
+                (append props (list 'tp-name layer-name)))))))))
    ;; Symbol - check if it's a layer or group name
    ((symbolp props)
     (cond