Merge branch 'jc/partial-remove'

* jc/partial-remove:
  Document ls-files --with-tree=<tree-ish>
  git-commit: partial commit of paths only removed from the index
  git-commit: Allow partial commit of file removal.

4 files changed, 123 insertions, 3 deletions

diff --git a/Documentation/git-ls-files.txt b/Documentation/git-ls-files.txt
index 997594549f..9e454f0a4d 100644
--- a/Documentation/git-ls-files.txt
+++ b/Documentation/git-ls-files.txt
@@ -15,7 +15,7 @@ SYNOPSIS
 		[-x <pattern>|--exclude=<pattern>]
 		[-X <file>|--exclude-from=<file>]
 		[--exclude-per-directory=<file>]
-		[--error-unmatch]
+		[--error-unmatch] [--with-tree=<tree-ish>]
 		[--full-name] [--abbrev] [--] [<file>]\*
 
 DESCRIPTION
@@ -81,6 +81,13 @@ OPTIONS
 	If any <file> does not appear in the index, treat this as an
 	error (return 1).
 
+--with-tree=<tree-ish>::
+	When using --error-unmatch to expand the user supplied
+	<file> (i.e. path pattern) arguments to paths, pretend
+	that paths which were removed in the index since the
+	named <tree-ish> are still present.  Using this option
+	with `-s` or `-u` options does not make any sense.
+
 -t::
 	Identify the file status with the following tags (followed by
 	a space) at the start of each line:
diff --git a/builtin-ls-files.c b/builtin-ls-files.c
index cce17b5ced..6c1db86e80 100644
--- a/builtin-ls-files.c
+++ b/builtin-ls-files.c
@@ -9,6 +9,7 @@
 #include "quote.h"
 #include "dir.h"
 #include "builtin.h"
+#include "tree.h"
 
 static int abbrev;
 static int show_deleted;
@@ -26,6 +27,7 @@ static int prefix_offset;
 static const char **pathspec;
 static int error_unmatch;
 static char *ps_matched;
+static const char *with_tree;
 
 static const char *tag_cached = "";
 static const char *tag_unmerged = "";
@@ -247,6 +249,8 @@ static void show_files(struct dir_struct *dir, const char *prefix)
 				continue;
 			if (show_unmerged && !ce_stage(ce))
 				continue;
+			if (ce->ce_flags & htons(CE_UPDATE))
+				continue;
 			show_ce_entry(ce_stage(ce) ? tag_unmerged : tag_cached, ce);
 		}
 	}
@@ -332,6 +336,67 @@ static const char *verify_pathspec(const char *prefix)
 	return real_prefix;
 }
 
+/*
+ * Read the tree specified with --with-tree option
+ * (typically, HEAD) into stage #1 and then
+ * squash them down to stage #0.  This is used for
+ * --error-unmatch to list and check the path patterns
+ * that were given from the command line.  We are not
+ * going to write this index out.
+ */
+static void overlay_tree(const char *tree_name, const char *prefix)
+{
+	struct tree *tree;
+	unsigned char sha1[20];
+	const char **match;
+	struct cache_entry *last_stage0 = NULL;
+	int i;
+
+	if (get_sha1(tree_name, sha1))
+		die("tree-ish %s not found.", tree_name);
+	tree = parse_tree_indirect(sha1);
+	if (!tree)
+		die("bad tree-ish %s", tree_name);
+
+	/* Hoist the unmerged entries up to stage #3 to make room */
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (!ce_stage(ce))
+			continue;
+		ce->ce_flags |= htons(CE_STAGEMASK);
+	}
+
+	if (prefix) {
+		static const char *(matchbuf[2]);
+		matchbuf[0] = prefix;
+		matchbuf [1] = NULL;
+		match = matchbuf;
+	} else
+		match = NULL;
+	if (read_tree(tree, 1, match))
+		die("unable to read tree entries %s", tree_name);
+
+	for (i = 0; i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		switch (ce_stage(ce)) {
+		case 0:
+			last_stage0 = ce;
+			/* fallthru */
+		default:
+			continue;
+		case 1:
+			/*
+			 * If there is stage #0 entry for this, we do not
+			 * need to show it.  We use CE_UPDATE bit to mark
+			 * such an entry.
+			 */
+			if (last_stage0 &&
+			    !strcmp(last_stage0->name, ce->name))
+				ce->ce_flags |= htons(CE_UPDATE);
+		}
+	}
+}
+
 static const char ls_files_usage[] =
 	"git-ls-files [-z] [-t] [-v] (--[cached|deleted|others|stage|unmerged|killed|modified])* "
 	"[ --ignored ] [--exclude=<pattern>] [--exclude-from=<file>] "
@@ -452,6 +517,10 @@ int cmd_ls_files(int argc, const char **argv, const char *prefix)
 			error_unmatch = 1;
 			continue;
 		}
+		if (!prefixcmp(arg, "--with-tree=")) {
+			with_tree = arg + 12;
+			continue;
+		}
 		if (!prefixcmp(arg, "--abbrev=")) {
 			abbrev = strtoul(arg+9, NULL, 10);
 			if (abbrev && abbrev < MINIMUM_ABBREV)
@@ -503,6 +572,15 @@ int cmd_ls_files(int argc, const char **argv, const char *prefix)
 	read_cache();
 	if (prefix)
 		prune_cache(prefix);
+	if (with_tree) {
+		/*
+		 * Basic sanity check; show-stages and show-unmerged
+		 * would not make any sense with this option.
+		 */
+		if (show_stage || show_unmerged)
+			die("ls-files --with-tree is incompatible with -s or -u");
+		overlay_tree(with_tree, prefix);
+	}
 	show_files(&dir, prefix);
 
 	if (ps_matched) {
diff --git a/git-commit.sh b/git-commit.sh
index 41538f16e5..bb113e858b 100755
--- a/git-commit.sh
+++ b/git-commit.sh
@@ -379,8 +379,11 @@ t,)
 		then
 			refuse_partial "Cannot do a partial commit during a merge."
 		fi
+
 		TMP_INDEX="$GIT_DIR/tmp-index$$"
-		commit_only=`git ls-files --error-unmatch -- "$@"` || exit
+		W=
+		test -z "$initial_commit" && W=--with-tree=HEAD
+		commit_only=`git ls-files --error-unmatch $W -- "$@"` || exit
 
 		# Build a temporary index and update the real index
 		# the same way.
@@ -401,7 +404,7 @@ t,)
 		(
 			GIT_INDEX_FILE="$NEXT_INDEX"
 			export GIT_INDEX_FILE
-			git update-index --remove --stdin
+			git update-index --add --remove --stdin
 		) || exit
 		;;
 	esac
diff --git a/t/t7501-commit.sh b/t/t7501-commit.sh
index 6bd3c9e3e0..b151b51a34 100644
--- a/t/t7501-commit.sh
+++ b/t/t7501-commit.sh
@@ -131,4 +131,36 @@ test_expect_success \
     'validate git-rev-list output.' \
     'diff current expected'
 
+test_expect_success 'partial commit that involves removal (1)' '
+
+	git rm --cached file &&
+	mv file elif &&
+	git add elif &&
+	git commit -m "Partial: add elif" elif &&
+	git diff-tree --name-status HEAD^ HEAD >current &&
+	echo "A	elif" >expected &&
+	diff expected current
+
+'
+
+test_expect_success 'partial commit that involves removal (2)' '
+
+	git commit -m "Partial: remove file" file &&
+	git diff-tree --name-status HEAD^ HEAD >current &&
+	echo "D	file" >expected &&
+	diff expected current
+
+'
+
+test_expect_success 'partial commit that involves removal (3)' '
+
+	git rm --cached elif &&
+	echo elif >elif &&
+	git commit -m "Partial: modify elif" elif &&
+	git diff-tree --name-status HEAD^ HEAD >current &&
+	echo "M	elif" >expected &&
+	diff expected current
+
+'
+
 test_done