split: support an arbitrary number of split files by default

* src/split.c (next_file_name): If `suffix_auto' is true and the first
suffix character is 'z', generate a new file file name adding `z' to
the prefix and increasing the suffix length by one.
(set_suffix_length): Disable auto suffix width in various cases.
* tests/split/suffix-auto-length: Test it.
* doc/coreutils.texi (split invocation): Mention it.
* NEWS (Improvements): Likewise.

2 files changed, 43 insertions, 0 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index 5e184ac32..d7a183737 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -253,6 +253,7 @@ TESTS =						\
   misc/sort-version				\
   misc/sort-NaN-infloop				\
   split/filter					\
+  split/suffix-auto-length			\
   split/suffix-length				\
   split/additional-suffix			\
   split/b-chunk					\
diff --git a/tests/split/suffix-auto-length b/tests/split/suffix-auto-length
new file mode 100755
index 000000000..dacc95158
--- /dev/null
+++ b/tests/split/suffix-auto-length
@@ -0,0 +1,42 @@
+#!/bin/sh
+# Test the suffix auto widening functionality
+
+# Copyright (C) 2012 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/init.sh"; path_prepend_ ../src
+print_ver_ split
+
+
+# ensure this feature is off when start number specified
+truncate -s12 file.in
+split file.in -b1 --numeric=89 && fail=1
+test "$(ls -1 x* | wc -l)" = 11 || fail=1
+rm -f x*
+
+# ensure this feature works when no start num specified
+truncate -s91 file.in
+for prefix in 'x' 'xx' ''; do
+    for add_suffix in '.txt' ''; do
+      split file.in "$prefix" -b1 --numeric --additional-suffix="$add_suffix" \
+        || fail=1
+      test "$(ls -1 $prefix*[0-9]*$add_suffix | wc -l)" = 91 || fail=1
+      test -e "${prefix}89$add_suffix" || fail=1
+      test -e "${prefix}9000$add_suffix" || fail=1
+      rm -f $prefix*[0-9]*$add_suffix
+    done
+done
+
+Exit $fail