make right-clicking on non-text offer copy and cut in the

popup menu

Extends append-editor-operation-menu-items so that when you
pass an editor and a position, it checks to see if that spot
has a non-string% snip and, if so, copies that one position
(or cuts it, depending).

Then, use that extension in DrRacket

closes PR 12791

collects/framework/private/keymap.rkt

@@ -344,7 +344,10 @@
                       
                       ((add-to-right-button-menu/before) m edit event)
                       
-                      (append-editor-operation-menu-items m)
+                      (append-editor-operation-menu-items 
+                       m #:popup-position 
+                       (list edit
+                             (send edit find-position (send event get-x) (send event get-y))))
                       (for-each
                        (λ (i)
                          (when (is-a? i selectable-menu-item<%>)

collects/mred/private/editor.rkt

@@ -7,6 +7,7 @@
          (for-syntax racket/base)
          (prefix-in wx: "kernel.rkt")
          (prefix-in wx: racket/snip/private/style)
+         (prefix-in wx: racket/snip/private/snip)
          (prefix-in wx: "wxme/keymap.rkt")
          (prefix-in wx: "wxme/editor.rkt")
          (prefix-in wx: "wxme/text.rkt")
@@ -592,31 +593,60 @@
 
 ;; ------------------------- Menus ----------------------------------------
 
-(define append-editor-operation-menu-items
+(define (append-editor-operation-menu-items m
-  (case-lambda
+                                            [text-only? #t]
-    [(m) (append-editor-operation-menu-items m #t)]
+                                            #:popup-position [popup-position #f])
-    [(m text-only?)
+  (unless (or (not popup-position)
+              (and (list? popup-position)
+                   (= 2 (length popup-position))
+                   (is-a? (list-ref popup-position 0) text%)
+                   (exact-nonnegative-integer? (list-ref popup-position 1))))
+    (raise-argument-error 'append-editor-operation-menu-items
+                          (format "~s" '(or/c #f (list/c (is-a?/c text%) exact-nonnegative-integer?)))
+                          popup-position))
   (menu-parent-only 'append-editor-operation-menu-items m)
-     (let* ([mk (lambda (name key op)
+  (let* ([mk (lambda (name key op [special-case? (λ () #f)] [special-go void])
                (make-object (class menu-item%
                               (inherit enable)
                               (define/override (on-demand)
                                 (let ([o (find-item-editor this)])
                                   (enable (and o
-                                                  (send o can-do-edit-operation? op)))))
+                                               (or (send o can-do-edit-operation? op)
+                                                   (special-case?))))))
                               (super-make-object
                                name m
                                (lambda (i e)
                                  (let* ([o (find-item-editor i)])
                                    (and o
-                                           (send o do-edit-operation op))))
+                                        (if (special-case?)
+                                            (special-go)
+                                            (send o do-edit-operation op)))))
                                key))))]
          [mk-sep (lambda () (make-object separator-menu-item% m))])
+    (define (special-case?)
+      (cond
+        [popup-position
+         (define snp (send (list-ref popup-position 0) find-snip 
+                           (list-ref popup-position 1)
+                           'after-or-none))
+         (and snp (not (is-a? snp wx:string-snip%)))]
+        [else
+         #f]))
+    (define (copy-special-go)
+      (send (list-ref popup-position 0)
+            copy #f 0 
+            (list-ref popup-position 1)
+            (+ (list-ref popup-position 1) 1)))
+    (define (cut-special-go)
+      (send (list-ref popup-position 0)
+            cut #f 0 
+            (list-ref popup-position 1)
+            (+ (list-ref popup-position 1) 1)))
     (mk "&Undo" #\z 'undo)
     (mk "Redo" #f 'redo)
     (mk-sep)
-       (mk "&Copy" #\c 'copy)
+    (mk "&Copy" #\c 'copy special-case? copy-special-go)
-       (mk "Cu&t" #\x 'cut)
+    (mk "Cu&t" #\x 'cut special-case? cut-special-go)
     (mk "&Paste" #\v 'paste)
     (if (eq? (system-type) 'windows)
         (mk "Delete" #f 'clear)
@@ -627,7 +657,7 @@
       (mk "Insert Text Box" #f 'insert-text-box)
       (mk "Insert Pasteboard Box" #f 'insert-pasteboard-box)
       (mk "Insert Image..." #f 'insert-image))
-       (void))]))
+    (void)))
 
 (define (append-editor-font-menu-items m)
   (menu-parent-only 'append-editor-font-menu-items m)

collects/scribblings/gui/editor-funcs.scrbl

@@ -103,7 +103,11 @@ Appends menu items to @racket[menu] to implement a
 }
 
 @defproc[(append-editor-operation-menu-items [menu (or/c (is-a?/c menu%) (is-a?/c popup-menu%))]
-                                             [text-only? any/c #t])
+                                             [text-only? any/c #t]
+                                             [#:popup-position 
+                                              popup-position 
+                                              (or/c #f (list/c (is-a?/c text%) exact-nonnegative-integer?))
+                                              #f])
          void?]{
 Appends menu items to @racket[menu] to implement the
  standard editor operations, such as cut and paste. The callback for
@@ -112,13 +116,17 @@ Appends menu items to @racket[menu] to implement the
  reached); if the result is an @racket[editor<%>] object,
 @xmethod[editor<%> do-edit-operation] is called on the editor.
 
-
-
 If @racket[text-only?] is @racket[#f], then menu items that insert
  non-text snips (such as @onscreen{Insert Image...}) are appended to
  the menu.
 
-
+If @racket[popup-position] is not @racket[#f], then @racket[append-editor-operation-menu-items]
+is expected to have been called to build a popup menu and the two elements
+of the list should be the @racket[text%] object where the mouse was clicked
+for the popup menu and the position where the click happened. In that case,
+the @onscreen{Copy} and @onscreen{Cut} menus are enabled when the click
+lands on a snip that is not a @racket[string-snip%], and the corresponding
+callbacks will copy and cut that one snip.
 
 }