Scribble: fix multi-line print output

Closes PR 11735

original commit: 1a5f41fd712384b409c760d15961af7b83e000ff

collects/scribble/eval.rkt

@@ -113,7 +113,7 @@
                        #f
                        (map (lambda (l)
                               (list (make-flow (list l))))
-                            flow-accum))))))))]
+                            (reverse flow-accum)))))))))]
            [(equal? #\newline v)
             (loop #f #f (add-line (add-string string-accum line-accum)
                                   flow-accum))]

collects/tests/scribble/docs.rkt

@@ -0,0 +1,35 @@
+#lang racket/base
+
+;; Use text renderer to check some Scribble functionality
+
+;; ----------------------------------------
+
+(require scribble/base-render
+         racket/file
+         racket/class
+         (prefix-in text:  scribble/text-render))
+
+(define (build-text-doc src-file dest-file)
+  (define dir (find-system-path 'temp-dir))
+  (let ([renderer (new (text:render-mixin render%)
+                    [dest-dir dir])])
+    (let* ([docs (list (dynamic-require `(file ,src-file) 'doc))]
+           [fns (list (build-path dir dest-file))]
+           [fp (send renderer traverse docs fns)]
+           [info (send renderer collect docs fns fp)])
+      (let ([r-info (send renderer resolve docs fns info)])
+        (send renderer render docs fns r-info)))))
+
+(define (check-text-build name)
+  (define src-file (string-append "docs/" name ".scrbl"))
+  (define expect-file (string-append "docs/" name ".txt"))
+  (build-text-doc src-file "gen.txt")
+  (unless (string=? (file->string expect-file)
+                    (file->string (build-path (find-system-path 'temp-dir)
+                                              "gen.txt")))
+    (error 'check-text-build "mismatch from: ~e expected: ~e"
+           src-file expect-file)))
+
+;; ----------------------------------------
+
+(check-text-build "print-lines")

collects/tests/scribble/docs/print-lines.scrbl

@@ -0,0 +1,21 @@
+#lang scribble/manual
+
+@(require scribble/eval)
+
+@title{Pretty-Print-Handler Bug Example}
+
+@(define the-eval (make-base-eval))
+@(interaction-eval
+  #:eval the-eval
+  (begin
+    (require racket/pretty)
+    (current-print pretty-print-handler)))
+
+@examples[#:eval the-eval
+'((x "positional 1") 
+    (rest ("positional 2" "positional 3"))
+    (a ())
+    (b ("b-arg"))
+    (c (("first c1" "second c1") ("first c2" "second c2")))
+    (d #f)
+    (e ()))]

collects/tests/scribble/docs/print-lines.txt

@@ -0,0 +1,18 @@
+
+Pretty-Print-Handler Bug Example
+
+Example:
+  > '((x "positional 1")
+        (rest ("positional 2" "positional 3"))
+        (a ())
+        (b ("b-arg"))
+        (c (("first c1" "second c1") ("first c2" "second c2")))
+        (d #f)
+        (e ()))
+  '((x "positional 1")
+    (rest ("positional 2" "positional 3"))
+    (a ())
+    (b ("b-arg"))
+    (c (("first c1" "second c1") ("first c2" "second c2")))
+    (d #f)
+    (e ()))