Implement a --dry-run option to git-quiltimport

Since large quilt trees like -mm can easily have patches
without clear authorship information, add a --dry-run
option to make the problem patches easy to find.

Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-quiltimport.txt

diff --git a/Documentation/git-quiltimport.txt b/Documentation/git-quiltimport.txt
index c66c82c..6e9a8c3 100644
--- a/Documentation/git-quiltimport.txt
+++ b/Documentation/git-quiltimport.txt
@@ -9,7 +9,7 @@
 SYNOPSIS
 --------
 [verse]
-'git-quiltimport' [--author <author>] [--patches <dir>]
+'git-quiltimport' [--dry-run] [--author <author>] [--patches <dir>]
 
 
 DESCRIPTION
@@ -29,6 +29,12 @@
 
 OPTIONS
 -------
+--dry-run::
+	Walk through the patches in the series and warn
+	if we cannot find all of the necessary information to commit
+	a patch.  At the time of this writing only missing author
+	information is warned about.
+
 --author Author Name <Author Email>::
 	The author name and email address to use when no author
 	information can be found in the patch description.

git-quiltimport.sh

diff --git a/git-quiltimport.sh b/git-quiltimport.sh
index dd4a198..12d9d0c 100755
--- a/git-quiltimport.sh
+++ b/git-quiltimport.sh
@@ -1,8 +1,9 @@
 #!/bin/sh
-USAGE='--author <author> --patches </path/to/quilt/patch/directory>'
+USAGE='--dry-run --author <author> --patches </path/to/quilt/patch/directory>'
 SUBDIRECTORY_ON=Yes
 . git-sh-setup
 
+dry_run=""
 quilt_author=""
 while case "$#" in 0) break;; esac
 do
@@ -19,6 +20,11 @@
 		shift
 		;;
 
+	--dry-run)
+		shift
+		dry_run=1
+		;;
+
 	--pa=*|--pat=*|--patc=*|--patch=*|--patche=*|--patches=*)
 		QUILT_PATCHES=$(expr "$1" : '-[^=]*\(.*\)')
 		shift
@@ -75,8 +81,12 @@
 		if [ -n "$quilt_author" ] ; then
 			GIT_AUTHOR_NAME="$quilt_author_name";
 			GIT_AUTHOR_EMAIL="$quilt_author_email";
+		elif [ -n "$dry_run" ]; then
+			echo "No author found in $patch_name" >&2;
+			GIT_AUTHOR_NAME="dry-run-not-found";
+			GIT_AUTHOR_EMAIL="dry-run-not-found";
 		else
-			echo "No author found in $patch_name";
+			echo "No author found in $patch_name" >&2;
 			echo "---"
 			cat $tmp_msg
 			echo -n "Author: ";
@@ -98,9 +108,11 @@
 		SUBJECT=$(echo $patch_name | sed -e 's/.patch$//')
 	fi
 
-	git-apply --index -C1 "$tmp_patch" &&
-	tree=$(git-write-tree) &&
-	commit=$((echo "$SUBJECT"; echo; cat "$tmp_msg") | git-commit-tree $tree -p $commit) &&
-	git-update-ref HEAD $commit || exit 4
+	if [ -z "$dry_run" ] ; then
+		git-apply --index -C1 "$tmp_patch" &&
+		tree=$(git-write-tree) &&
+		commit=$((echo "$SUBJECT"; echo; cat "$tmp_msg") | git-commit-tree $tree -p $commit) &&
+		git-update-ref HEAD $commit || exit 4
+	fi
 done
 rm -rf $tmp_dir || exit 5