[gnome-desktop-testing/optional-parallel-argument: 2/2] Allow --parallel to mean 'dynamic'

[Matthias Clasen <matthiasc src gnome org>]

commit 1f8dc393ccaacdaf86be7e103c93afea27e0fa8e
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Sep 17 12:08:19 2021 -0400

    Allow --parallel to mean 'dynamic'
    
    Having to specify --parallel=0 for 'maximum parallel'
    is unintuitive, so allos --parallel without argument
    to mean the same.
    
    Fixes: #2

 gnome-desktop-testing-runner.1     |  4 ++--
 src/gnome-desktop-testing-runner.c | 25 ++++++++++++++++++++++++-
 2 files changed, 26 insertions(+), 3 deletions(-)
---
diff --git a/gnome-desktop-testing-runner.1 b/gnome-desktop-testing-runner.1
index 358ba62..728dc89 100644
--- a/gnome-desktop-testing-runner.1
+++ b/gnome-desktop-testing-runner.1
@@ -72,8 +72,8 @@ access to the Journal is awkward, such as shell script or JavaScript.
 .TP
 \fB--parallel=\fIPROC\fR, \fB-p\fR \fIPROC\fR
 Run up to \fIPROC\fR tests in parallel. The default is 1, meaning do not
-run tests in parallel. If \fIPROC\fR is 0, detect the number of CPUs and
-run that many tests in parallel.
+run tests in parallel. If \fIPROC\fR is 0 or omitted, detect the number of
+CPUs and run that many tests in parallel.
 
 .TP
 \fB--quiet\fR
diff --git a/src/gnome-desktop-testing-runner.c b/src/gnome-desktop-testing-runner.c
index da49e14..c63afb4 100644
--- a/src/gnome-desktop-testing-runner.c
+++ b/src/gnome-desktop-testing-runner.c
@@ -393,10 +393,33 @@ static char **opt_dirs;
 static char *opt_status;
 static char *opt_log_msgid;
 
+static gboolean
+parse_parallel (const char  *option_name,
+                const char  *value,
+                gpointer     data,
+                GError     **error)
+{
+  if (value == NULL)
+    {
+      opt_parallel = 0;
+    }
+  else
+    {
+      guint64 num;
+
+      if (!g_ascii_string_to_unsigned (value, 10, 0, 65536, &num, error))
+        return FALSE;
+
+      opt_parallel = (int) num;
+    }
+
+  return TRUE;
+}
+
 static GOptionEntry options[] = {
   { "dir", 'd', 0, G_OPTION_ARG_STRING_ARRAY, &opt_dirs, "Only run tests from these dirs (default: all 
system data dirs)", "DIR" },
   { "list", 'l', 0, G_OPTION_ARG_NONE, &opt_list, "List matching tests", NULL },
-  { "parallel", 'p', 0, G_OPTION_ARG_INT, &opt_parallel, "Specify parallelization to PROC processors; 0 will 
be dynamic)", "PROC" },
+  { "parallel", 'p', 0, G_OPTION_ARG_CALLBACK, &parse_parallel, "Specify parallelization to PROC processors; 
omit the argument for dynamic)", "PROC" },
   { "first-root", 0, 0, G_OPTION_ARG_NONE, &opt_firstroot, "Only use first entry in XDG_DATA_DIRS", NULL },
   { "log-directory", 'L', 0, G_OPTION_ARG_FILENAME, &opt_log_directory, "Create a subdirectory with test 
logs", "DIR" },
   { "report-directory", 0, 0, G_OPTION_ARG_FILENAME, &opt_report_directory, "Create a subdirectory per 
failing test in DIR", "DIR" },