[glib] Added describe command to gsettings command-line tool.

[Jeremy Whiting <jpwhiting src gnome org>]

commit 8fd72838ced613b74b6c1bf5dcc92200fcf3db05
Author: Jeremy Whiting <jpwhiting kde org>
Date:   Thu Aug 25 12:39:33 2016 -0600

    Added describe command to gsettings command-line tool.
    
    describe command shows description of given gsettings key.
    Added documentation of describe command to gsettings man page.

 docs/reference/gio/gsettings.xml |   13 +++++++++++++
 gio/gsettings-tool.c             |   21 +++++++++++++++++++++
 2 files changed, 34 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gio/gsettings.xml b/docs/reference/gio/gsettings.xml
index 3f3ef97..9528b9d 100644
--- a/docs/reference/gio/gsettings.xml
+++ b/docs/reference/gio/gsettings.xml
@@ -50,6 +50,12 @@
   </cmdsynopsis>
   <cmdsynopsis>
     <command>gsettings</command>
+    <arg choice="plain">describe</arg>
+    <arg choice="plain"><replaceable>SCHEMA</replaceable><arg 
choice="opt">:<replaceable>PATH</replaceable></arg></arg>
+    <arg choice="plain"><replaceable>KEY</replaceable></arg>
+  </cmdsynopsis>
+  <cmdsynopsis>
+    <command>gsettings</command>
     <arg choice="plain">set</arg>
     <arg choice="plain"><replaceable>SCHEMA</replaceable><arg 
choice="opt">:<replaceable>PATH</replaceable></arg></arg>
     <arg choice="plain"><replaceable>KEY</replaceable></arg>
@@ -158,6 +164,13 @@ Queries the range of valid values for <replaceable>KEY</replaceable>.
 </varlistentry>
 
 <varlistentry>
+<term><option>describe</option></term>
+<listitem><para>
+Queries the description of valid values for <replaceable>KEY</replaceable>.
+</para></listitem>
+</varlistentry>
+
+<varlistentry>
 <term><option>set</option></term>
 <listitem><para>
 Sets the value of <replaceable>KEY</replaceable> to
diff --git a/gio/gsettings-tool.c b/gio/gsettings-tool.c
index 0026f55..88f304b 100644
--- a/gio/gsettings-tool.c
+++ b/gio/gsettings-tool.c
@@ -271,6 +271,14 @@ gsettings_list_recursively (void)
 }
 
 static void
+gsettings_description (void)
+{
+  const gchar *description;
+  description = g_settings_schema_key_get_description (global_schema_key);
+  g_print ("%s\n", description);
+}
+
+static void
 gsettings_range (void)
 {
   GVariant *range, *detail;
@@ -562,6 +570,12 @@ gsettings_help (gboolean     requested,
       synopsis = N_("SCHEMA[:PATH] KEY");
     }
 
+  else if (strcmp (command, "describe") == 0)
+    {
+      description = _("Query the description for KEY");
+      synopsis = N_("SCHEMA[:PATH] KEY");
+    }
+
   else if (strcmp (command, "set") == 0)
     {
       description = _("Set the value of KEY to VALUE");
@@ -615,6 +629,7 @@ gsettings_help (gboolean     requested,
         "  list-children             List children of a schema\n"
         "  list-recursively          List keys and values, recursively\n"
         "  range                     Queries the range of a key\n"
+        "  describe                  Queries the description of a key\n"
         "  get                       Get the value of a key\n"
         "  set                       Set the value of a key\n"
         "  reset                     Reset the value of a key\n"
@@ -752,6 +767,12 @@ main (int argc, char **argv)
   else if ((argc == 2 || argc == 3) && strcmp (argv[1], "list-recursively") == 0)
     function = gsettings_list_recursively;
 
+  else if (argc == 4 && strcmp (argv[1], "describe") == 0)
+    {
+      need_settings = FALSE;
+      function = gsettings_description;
+    }
+
   else if (argc == 4 && strcmp (argv[1], "range") == 0)
     {
       need_settings = FALSE;