adjust DrRacket to be able to populate the local pkg catalog

database in more convenient ways

- add a "update cache" button to online check syntax error message when
  a missing module exn is raised, but there are no suggestions
- add an "update cache" link to the missing module exn printout

pkgs/drracket-pkgs/drracket/drracket/private/debug.rkt

@@ -28,6 +28,7 @@ profile todo:
          mrlib/include-bitmap
          images/compile-time
          pkg/lib
+         pkg/gui
          (for-syntax images/icons/misc images/icons/style images/icons/control images/logos)
          (for-syntax racket/base)
          (submod "frame.rkt" install-pkg))
@@ -167,7 +168,7 @@ profile todo:
       (set-flags (cons 'handles-events (get-flags)))))
   
   (define clickable-image-snip%  (clickable-snip-mixin image-snip%))
-  (define clickable-string-snip%  
+  (define clickable-string-snip%
     (class (clickable-snip-mixin snip%)
       (define/override (get-extent dc x y wb hb db sb lb rb)
         (define-values (w h d a) (send dc get-text-extent str))
@@ -198,8 +199,22 @@ profile todo:
         (let ([n (new clickable-string-snip% [str str])])
           (send n set-callback (get-callback))
           n))
-      (super-new)))
+      (define/override (write f)
+        (define bts (string->bytes/utf-8 str))
+        (send f put (bytes-length bts) bts))
+      (super-new)
+      (inherit set-snipclass)
+      (set-snipclass clickable-string-snipclass)))
   (define (set-box/f b v) (when (box? b) (set-box! b v)))
+  (define clickable-string-snipclass
+    (new (class snip-class%
+           (define/override (read f)
+             (define str (bytes->string/utf-8 (or (send f get-unterminated-bytes) #"")))
+             (new clickable-string-snip% [str str]))
+           (super-new))))
+  (send clickable-string-snipclass set-classname "drclickable-string-snipclass")
+  (send clickable-string-snipclass set-version 0)
+  (send (get-the-snip-class-list) add clickable-string-snipclass)
   
   ;; make-note% : string -> (union class #f)
   (define (make-note% filename bitmap)
@@ -461,28 +476,41 @@ profile todo:
     (when (exn:missing-module? exn)
       (define mod ((exn:missing-module-accessor exn) exn))
       (define pkgs (pkg-catalog-suggestions-for-module mod))
-      (unless (null? pkgs)
-        (display "\n" (current-error-port))
-        (display "  packages that provide the missing module:" (current-error-port))
-        (for ([pkg (in-list pkgs)])
-          (eprintf "\n    ~a" pkg)
-          (when (port-writes-special? (current-error-port))
-            (define note (new clickable-string-snip% [str "[install]"]))
-            (send note set-callback 
-                  (λ (snp) 
-                    ;; =Kernel= =Handler=
-                    (define admin (send snp get-admin))
-                    (define canvas (and admin (send (send admin get-editor) get-canvas)))
-                    (define tlw (and canvas (send canvas get-top-level-window)))
-                    (install-pkg
-                     tlw
-                     (lambda (thunk)
-                       (parameterize ([error-display-handler drracket:init:original-error-display-handler])
-                         (thunk)))
-                     #:package-to-offer pkg)))
-            (eprintf "  ")
-            (write-special note (current-error-port)))))))
-  
+      (define update-pkgs-node (new clickable-string-snip% [str "[update catalog]"]))
+      (define (get-tlw snp)
+        (define admin (send snp get-admin))
+        (define canvas (and admin (send (send admin get-editor) get-canvas)))
+        (and canvas (send canvas get-top-level-window)))
+      (send update-pkgs-node set-callback 
+            (λ (snp)
+              (pkg-catalog-update-local/simple-status-dialog
+               #:parent (get-tlw snp))))
+      (cond
+        [(null? pkgs)
+         (when (port-writes-special? (current-error-port))
+           (display "\n  no packages suggestions are available " (current-error-port))
+           (write-special update-pkgs-node (current-error-port)))]
+        [else
+         (display "\n  packages that provide the missing module:" (current-error-port))
+         (when (port-writes-special? (current-error-port))
+           (display " " (current-error-port))
+           (write-special update-pkgs-node (current-error-port)))
+         (for ([pkg (in-list pkgs)])
+           (eprintf "\n    ~a" pkg)
+           (when (port-writes-special? (current-error-port))
+             (define note (new clickable-string-snip% [str "[install]"]))
+             (send note set-callback 
+                   (λ (snp) 
+                     ;; =Kernel= =Handler=
+                     (define tlw (get-tlw snp))
+                     (install-pkg
+                      tlw
+                      (lambda (thunk)
+                        (parameterize ([error-display-handler drracket:init:original-error-display-handler])
+                          (thunk)))
+                      #:package-to-offer pkg)))
+             (eprintf "  ")
+             (write-special note (current-error-port))))])))
   
   ;; =User=
   (define (exn->trace exn)

pkgs/drracket-pkgs/drracket/drracket/private/frame.rkt

@@ -2,7 +2,7 @@
 
 (module install-pkg racket/base
   (require racket/class
-           pkg/gui/main)
+           pkg/gui)
   (provide install-pkg
            pkg-manager)
 

pkgs/drracket-pkgs/drracket/drracket/private/module-language.rkt

@@ -27,6 +27,7 @@
          "local-member-names.rkt"
          "rectangle-intersect.rkt"
          pkg/lib
+         pkg/gui
          framework/private/logging-timer
          (submod "frame.rkt" install-pkg))
 
@@ -1246,6 +1247,12 @@
                (define missing-mods (exn-info-missing-mods error/status-message-str+srcloc))
                (with-handlers ([exn:fail? (λ (x) '())])
                  (pkg-catalog-suggestions-for-module missing-mods)))))
+          (define has-missing-mods?
+            (for/or ([error/status-message-str+srcloc (in-list error/status-message-strs+srclocs)]
+                     #:when (exn-info-missing-mods error/status-message-str+srcloc))
+              (define missing-mods (exn-info-missing-mods error/status-message-str+srcloc))
+              (not (null? missing-mods))))
+            
           (define (combine-msg vec)
             (define msg (exn-info-str vec))
             (define stack (exn-info-src-vecs vec))
@@ -1277,7 +1284,7 @@
                    (for/sum ([error/status-message-str+srcloc
                               (in-list error/status-message-strs+srclocs)])
                      (max 1 (length (exn-info-src-vecs error/status-message-str+srcloc))))])
-                install-suggestions)))
+                (and has-missing-mods? install-suggestions))))
       (define/public (hide-module-language-error-panel)
         (set! error/status-message-hidden? #t)
         (update-frame-expand-error))
@@ -1646,21 +1653,34 @@
             (send expand-error-message set-msgs 
                   expand-error-msgs expand-error-msg-is-err? expand-error-msgs+stack)
             (send expand-error-install-suggestions-panel change-children (λ (l) '()))
-            (for ([suggestion-pkg (in-list expand-error-install-suggestions)])
-              (new button% 
-                   [parent expand-error-install-suggestions-panel]
-                   [callback 
-                    (λ (_1 _2)
-                      (install-pkg
-                       (send expand-error-install-suggestions-panel get-top-level-window)
-                       (lambda (thunk)
-                         (parameterize ([error-display-handler 
-                                         drracket:init:original-error-display-handler])
-                           (thunk)))
-                       #:package-to-offer suggestion-pkg))]
-                   [font small-control-font]
-                   [label (format (string-constant install-package-button) 
-                                  suggestion-pkg)]))
+            (when expand-error-install-suggestions
+              (cond
+                [(null? expand-error-install-suggestions) 
+                 (new button% 
+                      [parent expand-error-install-suggestions-panel]
+                      [callback 
+                       (λ (_1 _2)
+                         (pkg-catalog-update-local/simple-status-dialog 
+                          #:parent
+                          (send expand-error-install-suggestions-panel get-top-level-window)))]
+                      [font small-control-font]
+                      [label (string-constant update-catalog)])]
+                [else
+                 (for ([suggestion-pkg (in-list expand-error-install-suggestions)])
+                   (new button% 
+                        [parent expand-error-install-suggestions-panel]
+                        [callback 
+                         (λ (_1 _2)
+                           (install-pkg
+                            (send expand-error-install-suggestions-panel get-top-level-window)
+                            (lambda (thunk)
+                              (parameterize ([error-display-handler 
+                                              drracket:init:original-error-display-handler])
+                                (thunk)))
+                            #:package-to-offer suggestion-pkg))]
+                        [font small-control-font]
+                        [label (format (string-constant install-package-button) 
+                                       suggestion-pkg)]))]))
             (send expand-error-button-parent-panel change-children
                   (λ (l)
                     (list (cond