tests: add tests to ensure quoting to tty

* tests/misc/tty-quoting.sh: Add positive test for
basename, du, ls, readlink, and realpath quoting.
* tests/local.mk: Reference the new test.

diff --git a/tests/local.mk b/tests/local.mk
index f0fdd00865eaa4e08f23cfecd0fdea4caeaa72b8..a002904a777a1d386689c459892444a3dba53718 100644 (file)
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -186,6 +186,7 @@ all_tests =                                 \
   tests/misc/read-errors.sh                    \
   tests/misc/responsive.sh                     \
   tests/misc/traversal-missing.sh              \
+  tests/misc/tty-quoting.sh                    \
   tests/misc/warning-errors.sh                 \
   tests/misc/write-errors.sh                   \
   tests/tail/basic-seek.sh                     \

diff --git a/tests/misc/tty-quoting.sh b/tests/misc/tty-quoting.sh
new file mode 100755 (executable)
index 0000000..fe3f812
--- /dev/null
+++ b/tests/misc/tty-quoting.sh
@@ -0,0 +1,63 @@
+#!/bin/sh
+# Test quoting output when standard output is a terminal.
+
+# Copyright (C) 2026 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 <https://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ basename du ls readlink realpath printf test
+require_strace_ ioctl
+
+touch 'b ar' || framework_failure_
+ln -s 'b ar' 'f oo' || framework_failure_
+
+# Induce terminal probes to return true.
+# Also ensure a single ioctl(TCGETS) is intercepted.
+run_tty_ ()
+{
+  strace --quiet=all -o run_tty.strace -e trace=ioctl \
+    -e inject=ioctl:retval=0 "$@" &&
+
+  # Return status of these also so commands' tty detection
+  # is correlated with that of the initial 'test -t 1' probe
+  test "$(wc -l < run_tty.strace)" = 1 &&
+  grep 'ioctl.*TCGETS' run_tty.strace >/dev/null
+}
+
+run_tty_ env test -t 1 ||
+ skip_ 'strace cannot make standard output appear to be a terminal'
+
+# We're redirecting to file so this doesn't happen on glibc
+# but be defensive on systems that might probe in this case.
+run_tty_ env printf foo >printf.t &&
+ skip_ 'libc buffering induced a tty probe'
+
+for cmd in basename du 'ls -w0' readlink 'realpath --relative-to=.'; do
+  test "$cmd" = 'du' && field=2 || field=1
+
+  run_tty_ $cmd 'f oo' >quoted.t || fail=1
+  cut -f$field- quoted.t >quoted || framework_failure_
+
+  # Note ls theoretically doesn't need isatty() for a specified QUOTING_STYLE
+  # but it does need it to determine appropriate output format.
+  QUOTING_STYLE=literal run_tty_ $cmd 'f oo' >unquoted.t || fail=1
+  cut -f$field- unquoted.t >unquoted || framework_failure_
+
+  env printf '%q\n' "$(cat unquoted)" >printf_quoted || framework_failure_
+
+  compare quoted printf_quoted || fail=1
+done
+
+Exit $fail