Add rm -v.

Gentoo removes verbosely when building packages, for example vim-core:
https://github.com/gentoo/gentoo/blob/665eaa8/app-editors/vim-core/vim-core-8.1.0648.ebuild#L120

Implement like toy cp, without prepending an escape sign to quotation
marks in filenames. Document in a test this difference from coreutils
but similarity to busybox. How do other implementations handle such
escapes? If it matters, would you approach it with a loop and multiple
prints or somehow else?

Short help description follows 141a075, consistent with other commands.

2 files changed, 20 insertions, 3 deletions

diff --git a/tests/rm.test b/tests/rm.test
index 95710c82..42727442 100755
--- a/tests/rm.test
+++ b/tests/rm.test
@@ -48,3 +48,13 @@ mkdir -p one && touch one/two && chmod 000 one
 SKIP_HOST=1 testing "-rf 000 dir" \
   "rm -rf one 2>/dev/null && [ ! -e one ] && echo yes" "yes\n" "" ""
 chmod 777 one 2>/dev/null ; rm -rf one
+
+mkdir -p d1
+touch d1/f1.txt d1/f2.txt
+testing "-rv dir" \
+  "rm -rv d1" "rm 'd1/f1.txt'\nrm 'd1/f2.txt'\nrmdir 'd1'\n" "" ""
+rm -rf d1
+
+touch "'"
+testing "-v \\'" "rm -v \\'" "rm '''\n" "" "" # TODO: coreutils escapes quote
+rm -f \'
diff --git a/toys/posix/rm.c b/toys/posix/rm.c
index 608e1ca1..6c64e13f 100644
--- a/toys/posix/rm.c
+++ b/toys/posix/rm.c
@@ -4,19 +4,20 @@
  *
  * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/rm.html
 
-USE_RM(NEWTOY(rm, "fiRr[-fi]", TOYFLAG_BIN))
+USE_RM(NEWTOY(rm, "fiRrv[-fi]", TOYFLAG_BIN))
 
 config RM
   bool "rm"
   default y
   help
-    usage: rm [-fiRr] FILE...
+    usage: rm [-fiRrv] FILE...
 
     Remove each argument from the filesystem.
 
     -f	Force: remove without confirmation, no error if it doesn't exist
     -i	Interactive: prompt for confirmation
     -rR	Recursive: remove directory contents
+    -v	Verbose
 */
 
 #define FOR_rm
@@ -68,7 +69,13 @@ static int do_rm(struct dirtree *try)
   }
 
 skip:
-  if (unlinkat(fd, try->name, using)) {
+  if (!unlinkat(fd, try->name, using)) {
+    if (flags & FLAG_v) {
+      char *s = dirtree_path(try, 0);
+      printf("%s%s '%s'\n", toys.which->name, dir ? "dir" : "", s);
+      free(s);
+    }
+  } else {
     if (!dir || try->symlink != (char *)2) perror_msg_raw(try->name);
 nodelete:
     if (try->parent) try->parent->symlink = (char *)2;