add --no-fetch option

there is no point in re-fetching all repositories just because an update
failed due to local modifications.

Change-Id: Ie9883586d77f3310058353844f0bbcfb0b775ebb
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>

init-repository

@@ -82,6 +82,9 @@ Options:
     --no-update
         Skip the `git submodule update' command.
 
+    --no-fetch
+        Skip the `git fetch' commands. Implied by --no-update.
+
     --branch
         Instead of checking out specific SHA1s, check out the submodule
         branches that correspond with the current supermodule commit. By
@@ -213,6 +216,7 @@ sub parse_arguments
         'ignore-submodules'   => 0 ,
         'mirror-url'          => "",
         'update'              => 1 ,
+        'fetch'               => 1 ,
         'module-subset'       => "default",
     );
 
@@ -227,6 +231,7 @@ sub parse_arguments
         'mirror=s'          =>  \$self->{qw{ mirror-url        }},
         'quiet'             =>  \$self->{qw{ quiet             }},
         'update!'           =>  \$self->{qw{ update            }},
+        'fetch!'            =>  \$self->{qw{ fetch             }},
         'module-subset=s'   =>  \$self->{qw{ module-subset     }},
 
         'help|?'            =>  sub { printUsage(1);            },
@@ -245,6 +250,8 @@ sub parse_arguments
     $self->{'module-subset'} =~ s/\bdefault\b/preview,essential,addon,deprecated/;
     $self->{'module-subset'} = [ split(/,/, $self->{'module-subset'}) ];
 
+    $self->{'fetch'} = 0 if (!$self->{'update'});
+
     return;
 }
 
@@ -466,9 +473,11 @@ sub git_clone_one_submodule
         }
     }
 
+    my $do_clone = (! -e "$submodule/.git");
+
     my $url = $self->{'base-url'}.$repo_basename;
     my $mirror;
-    if ($mirror_url) {
+    if ($mirror_url && ($do_clone || $self->{fetch})) {
         $mirror = $mirror_url.$repo_basename;
     }
 
@@ -481,7 +490,6 @@ sub git_clone_one_submodule
         }
     }
 
-    my $do_clone = (! -e "$submodule/.git");
     if ($do_clone) {
         if ($branch) {
             push @reference_args, '--branch', $branch;
@@ -501,14 +509,14 @@ sub git_clone_one_submodule
         $self->exe('git', 'config', 'remote.mirror.fetch', '+refs/heads/*:refs/remotes/mirror/*');
     }
 
-    if (!$do_clone && $self->{update}) {
+    if (!$do_clone && $self->{fetch}) {
         # If we didn't clone, fetch from the right location. We always update
         # the origin remote, so that submodule update --remote works.
         $self->exe('git', 'config', 'remote.origin.url', ($mirror ? $mirror : $url));
         $self->exe('git', 'fetch', 'origin');
     }
 
-    if (!($do_clone || $self->{update}) || $mirror) {
+    if (!($do_clone || $self->{fetch}) || $mirror) {
         # Leave the origin configured to the canonical URL. It's already correct
         # if we cloned/fetched without a mirror; otherwise it may be anything.
         $self->exe('git', 'config', 'remote.origin.url', $url);