From c107ad1f7743ea4766e8f281fae8d8b3f39fedbd Mon Sep 17 00:00:00 2001
From: Robby Findler <robby@racket-lang.org>
Date: Sat, 6 Jul 2013 10:33:19 -0500
Subject: [PATCH] fix c:c;c:e for empty sequences

closes PR 13905
---
 .../gui-lib/framework/private/racket.rkt      | 25 +++++++-------
 .../gui-test/framework/tests/racket.rkt       | 34 +++++++++++--------
 2 files changed, 33 insertions(+), 26 deletions(-)

diff --git a/pkgs/gui-pkgs/gui-lib/framework/private/racket.rkt b/pkgs/gui-pkgs/gui-lib/framework/private/racket.rkt
index be3201d10b..17e95edcc7 100644
--- a/pkgs/gui-pkgs/gui-lib/framework/private/racket.rkt
+++ b/pkgs/gui-pkgs/gui-lib/framework/private/racket.rkt
@@ -546,6 +546,7 @@
                     #f)]
                [last-para (and last
                                (position-paragraph last))])
+          (define sizing-dc (or (get-dc) (make-object bitmap-dc% (make-bitmap 1 1))))
           (letrec
               ([find-offset
                 (λ (start-pos)
@@ -568,7 +569,7 @@
                   (position-location start-pos start-x #f #t #t)
                   (position-location end-pos end-x #f #t #t)
                   (define-values (w _1 _2 _3)
-                    (send (get-dc) get-text-extent "x" 
+                    (send sizing-dc get-text-extent "x" 
                           (send (send (get-style-list)
                                       find-named-style "Standard")
                                 get-font)))
@@ -1141,17 +1142,17 @@
     
     (define/public (kill-enclosing-parens begin-inner)
       (begin-edit-sequence)
-      (let ([begin-outer (find-up-sexp begin-inner)])
-        (cond
-          [begin-outer
-            (let ([end-outer (get-forward-sexp begin-outer)])
-              (cond
-                [(and end-outer (> (- end-outer begin-outer) 2))
-                 (delete (- end-outer 1) end-outer)
-                 (delete begin-outer (+ begin-outer 1))
-                 (tabify-selection begin-outer (- end-outer 2))]
-                [else (bell)]))]
-          [else (bell)]))
+      (define begin-outer (find-up-sexp begin-inner))
+      (cond
+        [begin-outer
+          (define end-outer (get-forward-sexp begin-outer))
+          (cond
+            [(and end-outer (>= (- end-outer begin-outer) 2))
+             (delete (- end-outer 1) end-outer)
+             (delete begin-outer (+ begin-outer 1))
+             (tabify-selection begin-outer (- end-outer 2))]
+            [else (bell)])]
+        [else (bell)])
       (end-edit-sequence))
     
     ;; change the parens following the cursor from () to [] or vice versa
diff --git a/pkgs/gui-pkgs/gui-test/framework/tests/racket.rkt b/pkgs/gui-pkgs/gui-test/framework/tests/racket.rkt
index d50fa94590..4502fe4807 100644
--- a/pkgs/gui-pkgs/gui-test/framework/tests/racket.rkt
+++ b/pkgs/gui-pkgs/gui-test/framework/tests/racket.rkt
@@ -94,14 +94,15 @@
 (test-magic-square-bracket 'local2 "(local [(define x 1)] " "(local [(define x 1)] (")
 
 
-(define (test-insert-close-paren/proc line
-                                      pos char flash? fixup? smart-skip
-                                      before after)
+(define (test-message-send/proc line before after pos msg . args)
+  (define (maybe-quote x)
+    (cond
+      [(or (number? x) (boolean? x) (string? x)) x]
+      [else `',x]))
   (test
    (string->symbol (format "line ~a: ~s"
                            line
-                           `(test-insert-close-paren ,pos ,char ,flash? ,fixup? ',smart-skip
-                                                     ,before ,after)))
+                           `(,msg ,@(map maybe-quote args))))
    (λ (x) (equal? x after))
    (λ ()
      (queue-sexp-to-mred
@@ -111,19 +112,24 @@
          (define ec (new editor-canvas% [parent f] [editor t]))
          (send t insert ,before)
          (send t set-position ,pos)
-         (send t insert-close-paren ,pos ,char ,flash? ,fixup? ',smart-skip)
+         (send t ,msg ,@(map maybe-quote args))
          (send t get-text))))))
-(define-syntax (test-insert-close-paren stx)
+(define-syntax (test-message-send stx)
   (syntax-case stx ()
-    [(_ . args)
+    [(_ before after pos mth . args)
      (with-syntax ([line (syntax-line stx)])
-       #'(test-insert-close-paren/proc line . args))]))
+       #'(test-message-send/proc line before after pos 'mth . args))]))
 
-(test-insert-close-paren 0 #\] #t #t 'adjacent "" "]")
-(test-insert-close-paren 0 #\] #t #t #f "" "]")
-(test-insert-close-paren 1 #\] #t #t #f "(" "()")
-(test-insert-close-paren 1 #\] #f #f #f "(" "(]")
-(test-insert-close-paren 0 #\] #t #t 'forward "" "]")
+(test-message-send ""  "]"  0 insert-close-paren 0 #\] #t #t 'adjacent)
+(test-message-send ""  "]"  0 insert-close-paren 0 #\] #t #t #f)
+(test-message-send "(" "()" 1 insert-close-paren 1 #\] #t #t #f)
+(test-message-send "(" "(]" 1 insert-close-paren 1 #\] #f #f #f)
+(test-message-send ""  "]"  0 insert-close-paren 0 #\] #t #t 'forward)
+
+(test-message-send "(1)" "1" 1 kill-enclosing-parens 1)
+(test-message-send "(1 2 3)" "1 2 3" 3 kill-enclosing-parens 3)
+(test-message-send "()" "" 1 kill-enclosing-parens 1)
+(test-message-send "(1\n 2\n 3)" "1\n2\n3" 1 kill-enclosing-parens 1) ;; test tabify call
 
 ;; tests what happens when a given key/s is/are typed in an editor with initial
 ;;       text and cursor position, under different settings of the auto-parentheses and