From 8890f72c3a20198e2a25337b2569c41a643b922b Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Thu, 18 Aug 2011 13:05:37 -0600
Subject: [PATCH] `scribble' reports broken cross references by default

original commit: 39edc5a5991d17c8becfc7a1b44665fb5cd9d622
---
 collects/scribble/render.rkt                 | 11 +++++++++--
 collects/scribble/run.rkt                    |  2 +-
 collects/scribblings/scribble/renderer.scrbl | 11 ++++++++---
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/collects/scribble/render.rkt b/collects/scribble/render.rkt
index 79e8b74c..f9ee4a72 100644
--- a/collects/scribble/render.rkt
+++ b/collects/scribble/render.rkt
@@ -39,7 +39,8 @@
                 #:xrefs [xrefs null]
                 #:info-in-files [info-input-files null]
                 #:info-out-file [info-output-file #f]
-                #:quiet? [quiet? #t])
+                #:quiet? [quiet? #t]
+                #:warn-undefined? [warn-undefined? (not quiet?)])
   (when dest-dir (make-directory* dest-dir))
   (let ([renderer (new (render-mixin render%)
                        [dest-dir dest-dir]
@@ -73,5 +74,11 @@
           (let ([s (send renderer serialize-info r-info)])
             (with-output-to-file info-output-file
               #:exists 'truncate/replace
-              (lambda () (write s))))))
+              (lambda () (write s)))))
+        (when warn-undefined?
+          (let ([undef (send renderer get-undefined r-info)])
+            (unless (null? undef)
+              (eprintf "Warning: some cross references may be broken due to undefined tags:\n")
+              (for ([t (in-list undef)])
+                (eprintf " ~s\n" t))))))
       (void))))
diff --git a/collects/scribble/run.rkt b/collects/scribble/run.rkt
index 3b080fe6..23475084 100644
--- a/collects/scribble/run.rkt
+++ b/collects/scribble/run.rkt
@@ -91,7 +91,7 @@
     (current-info-input-files
      (cons file (current-info-input-files)))]
    #:once-each
-   [("--quiet") "suppress output-file reporting"
+   [("--quiet") "suppress output-file and undefined-tag reporting"
     (current-quiet #t)]
    #:args (file . another-file)
    (let ([files (cons file another-file)])
diff --git a/collects/scribblings/scribble/renderer.scrbl b/collects/scribblings/scribble/renderer.scrbl
index 932530c1..6fad20de 100644
--- a/collects/scribblings/scribble/renderer.scrbl
+++ b/collects/scribblings/scribble/renderer.scrbl
@@ -46,7 +46,8 @@ function to render a document.
                  [#:info-out-file info-out-file (or/c #f path-string?) #f]
                  [#:redirect redirect (or/c #f string?) #f]
                  [#:redirect-main redirect-main (or/c #f string?) #f]
-                 [#:quiet? quiet? any/c #f])
+                 [#:quiet? quiet? any/c #t]
+                 [#:warn-undefined? warn-undefined? any/c (not quiet?)])
           void?]{
 
 Renders the given @racket[docs], each with an output name derived from
@@ -78,8 +79,12 @@ to the @racket[set-external-tag-path] and
 @racketmodname[scribble/html-render], so they should be
 non-@racket[#f] only for HTML rendering.
 
-If @racket[quiet?] is a true value, output-file information is written
-to the current output port.}
+If @racket[quiet?] is a false value, output-file information is
+written to the current output port.
+
+If @racket[warn-undefined?] is a true value, then references to
+missing cross-reference targets trigger a warning message on the
+current error port.}
 
 
 @section{Base Renderer}