Fix defstruct with an empty list of field options

Author: shhyou

scribble-lib/scribble/private/manual-proc.rkt

@@ -17,6 +17,7 @@
          "manual-method.rkt"
          "manual-ex.rkt"
          "on-demand.rkt"
+         racket/match
          racket/string
          racket/list
          racket/contract
@@ -897,10 +898,15 @@
                                (append (if (pair? name) name (list name))
                                        (map field-name fields)))
                           (map (lambda (f)
-                                 (if (pair? (car f))
-                                     (+ 3 2 (string-length (keyword->string
-                                                            (cadar f))))
-                                     0))
+                                 (match (car f)
+                                   [(? symbol?) 0]
+                                   [(list name) 2] ;; the extra [ ]
+                                   [(list* name field-opts)
+                                    ;; '[' ']'
+                                    (apply + 2
+                                           (for/list ([field-opt (in-list field-opts)])
+                                             ;; and " #:"
+                                             (+ 3 (string-length (keyword->string field-opt)))))]))
                                fields)))])
             (cond
               [(and (short-width . < . max-proto-width)

scribble-test/tests/scribble/docs/manual-ex.rkt

@@ -20,6 +20,7 @@
 
 (define-struct pt (x y))
 (struct pn (x y))
+(struct counter (name [count #:mutable]))
 
 (define v 10)
 

scribble-test/tests/scribble/docs/manual.scrbl

@@ -99,6 +99,14 @@ A function, again, not a link target, documented to return @racket[10] using a d
 
 @defstruct[#:link-target? #f pt ([x real?] [y real?]) #:mutable]{A mutable structure type with extra name, again.}
 
+@defstruct*[#:link-target? #f counter ([name symbol?] [(count) exact-nonnegative-integer?])]{A struct with an (empty) list of field options.}
+
+@defstruct*[counter ([name symbol?] [(count #:mutable) exact-nonnegative-integer?])]{Another struct with a mutable field.}
+
+@defstruct*[#:link-target? #f counter ([name symbol?] [(count #:auto) exact-nonnegative-integer?])]{A struct with an automatic field.}
+
+@defstruct*[#:link-target? #f counter ([name symbol?] [(count #:auto #:mutable) exact-nonnegative-integer?])]{A struct with both.}
+
 @defstruct[a-struct-with-an-extremely-long-name-and-no-fields ()]{Used to raise error, taking car of empty fields list. Reported by Carlos Lopez, 2017-03-11.}
 
 

scribble-test/tests/scribble/docs/manual.txt

@@ -248,6 +248,30 @@ A structure type with extra name, again.
 
 A mutable structure type with extra name, again.
 
+(struct counter (name [count]))     
+  name : symbol?                    
+  count : exact-nonnegative-integer?
+
+A struct with an (empty) list of field options.
+
+(struct counter (name [count #:mutable]))
+  name : symbol?                         
+  count : exact-nonnegative-integer?     
+
+Another struct with a mutable field.
+
+(struct counter (name [count #:auto]))
+  name : symbol?                      
+  count : exact-nonnegative-integer?  
+
+A struct with an automatic field.
+
+(struct counter (name [count #:auto #:mutable]))
+  name : symbol?                                
+  count : exact-nonnegative-integer?            
+
+A struct with both.
+
 (struct a-struct-with-an-extremely-long-name-and-no-fields ()
     #:extra-constructor-name                                 
     make-a-struct-with-an-extremely-long-name-and-no-fields)