[options] add '--Print' command-line option

docs/options.md

@@ -51,6 +51,8 @@
     -N, --print [EVENT:]FORMAT  Write FORMAT during EVENT (default 'prepare')
                                 to standard output. Examples: 'id' or
                                 'post:{md5[:8]}'
+    --Print [EVENT:]FORMAT      Like --print, but also sets --no-download,
+                                --no-skip, and disables other output to stdout
     --print-to-file [EVENT:]FORMAT FILE
                                 Append FORMAT during EVENT to FILE
     --list-modules              Print a list of available extractor modules

gallery_dl/option.py

@@ -156,7 +156,11 @@ class UgoiraAction(argparse.Action):
 class PrintAction(argparse.Action):
     def __call__(self, parser, namespace, value, option_string=None):
         if self.const:
-            filename = self.const
+            if self.const == "+":
+                namespace.options.append(((), "skip", False))
+                namespace.options.append(((), "download", False))
+                namespace.options.append((("output",), "mode", False))
+            filename = "-"
             base = None
             mode = "w"
         else:
@@ -397,6 +401,13 @@ def build_parser():
         help=("Write FORMAT during EVENT (default 'prepare') to standard "
               "output. Examples: 'id' or 'post:{md5[:8]}'"),
     )
+    output.add_argument(
+        "--Print",
+        dest="postprocessors", metavar="[EVENT:]FORMAT",
+        action=PrintAction, const="+",
+        help=("Like --print, but also sets --no-download, --no-skip, "
+              "and disables other output to stdout"),
+    )
     output.add_argument(
         "--print-to-file",
         dest="postprocessors", metavar="[EVENT:]FORMAT FILE",