From 3a273bd2b052c1c04c60a0f6d381961c3dbced48 Mon Sep 17 00:00:00 2001
From: Vincent St-Amour <stamourv@racket-lang.org>
Date: Thu, 27 Mar 2014 16:23:35 -0400
Subject: [PATCH] Make profile and profile-thunk return the value of the
 profiled expression.

Closes PR14404.
---
 .../profile/scribblings/toplevel.scrbl        | 14 +++-----
 pkgs/profile-pkgs/profile-lib/info.rkt        |  2 +-
 pkgs/profile-pkgs/profile-lib/main.rkt        | 35 +++++++++++++------
 3 files changed, 30 insertions(+), 21 deletions(-)

diff --git a/pkgs/profile-pkgs/profile-doc/profile/scribblings/toplevel.scrbl b/pkgs/profile-pkgs/profile-doc/profile/scribblings/toplevel.scrbl
index 15dd7d6b0b..45f13d5955 100644
--- a/pkgs/profile-pkgs/profile-doc/profile/scribblings/toplevel.scrbl
+++ b/pkgs/profile-pkgs/profile-doc/profile/scribblings/toplevel.scrbl
@@ -26,11 +26,12 @@ intended as a convenient tool for profiling code.
                             (profile? . -> . any/c)))
            #f]
           [#:use-errortrace? use-errortrace? any/c #f])
-         void?]{
+         any/c]{
 
 Executes the given @racket[thunk] and collect profiling data during
-execution, eventually analyzing and rendering this.  Keyword arguments
-can customize the profiling:
+execution, eventually analyzing and rendering this. Returns the value
+of the profiled expression.
+Keyword arguments can customize the profiling:
 @itemize[
 
 @item{The profiler works by starting a ``sampler'' thread to
@@ -69,12 +70,7 @@ can customize the profiling:
 @item{Once the computation is done and the sampler is stopped, the
   accumulated data is analyzed (by @racket[analyze-samples]) and the
   resulting profile value is sent to the @racket[renderer] function.
-  See @secref["renderers"] for available renderers.  You can also use
-  @racket[values] as a ``renderer''---in this case
-  @racket[profile-thunk] returns the analyzed information which can
-  now be rendered multiple times, or saved for rendering directly
-  using one of the renderers, perhaps multiple times for different
-  views.}
+  See @secref["renderers"] for available renderers.}
 
 @item{To provide feedback information during execution, specify a
   @racket[periodic-renderer].  This should be a list holding a delay
diff --git a/pkgs/profile-pkgs/profile-lib/info.rkt b/pkgs/profile-pkgs/profile-lib/info.rkt
index 9cb70b8b80..5334dffa6e 100644
--- a/pkgs/profile-pkgs/profile-lib/info.rkt
+++ b/pkgs/profile-pkgs/profile-lib/info.rkt
@@ -7,4 +7,4 @@
 
 (define pkg-desc "implementation (no documentation) part of \"profile\"")
 
-(define pkg-authors '(eli))
+(define pkg-authors '(eli stamourv))
diff --git a/pkgs/profile-pkgs/profile-lib/main.rkt b/pkgs/profile-pkgs/profile-lib/main.rkt
index a6bb5f932c..c2992e02d9 100644
--- a/pkgs/profile-pkgs/profile-lib/main.rkt
+++ b/pkgs/profile-pkgs/profile-lib/main.rkt
@@ -28,17 +28,17 @@
              (renderer (analyze-samples (sampler 'get-snapshots)))
              (loop))
            (thread loop))))
-  (define (run) (for ([i (in-range rpt)]) (thunk)))
-  (with-handlers ([void (λ (e) (eprintf "profiled thunk error: ~a\n"
-                                        (if (exn? e)
-                                          (exn-message e)
-                                          (format "~e" e))))])
-    (if threads?
-      (parameterize ([current-custodian cust]) (run))
-      (run)))
-  (when periodic-thread (kill-thread periodic-thread))
-  (sampler 'stop)
-  (renderer (analyze-samples (sampler 'get-snapshots))))
+  (define (run) (for/last ([i (in-range rpt)]) (thunk)))
+  (begin0 (with-handlers ([void (λ (e) (eprintf "profiled thunk error: ~a\n"
+                                                (if (exn? e)
+                                                    (exn-message e)
+                                                    (format "~e" e))))])
+            (if threads?
+                (parameterize ([current-custodian cust]) (run))
+                (run)))
+    (when periodic-thread (kill-thread periodic-thread))
+    (sampler 'stop)
+    (renderer (analyze-samples (sampler 'get-snapshots)))))
 
 (define-syntax (profile stx)
   (syntax-case stx ()
@@ -85,3 +85,16 @@
          (list 0.5 text:render)
          )
 |#
+
+(module+ test
+  (require rackunit racket/string racket/list)
+  ;; `profile' and `profile-thunk' should return the value of the
+  ;; profiled expression
+  (check-equal?
+   (profile (for/last ([i (in-range 1000 5 -1)])
+              (string-join (map number->string (range i)))))
+   "0 1 2 3 4 5")
+  (check-equal?
+   (profile-thunk (lambda () (for/last ([i (in-range 1000 5 -1)])
+                               (string-join (map number->string (range i))))))
+   "0 1 2 3 4 5"))