Add conditional patch to prevent FTBFS on Hurd in case of wrong test assumptions

debian/rules now calls debian/patch-test-suite.sh with some parameters
to modify or unmodify Test/C02cond.ztst in a way that either the
character device for testing zsh's -c either exists or the test for -c
is disabled at all.

There are three ways in which debian/patch-test-suite.sh can patch
Test/C02cond.ztst:

* Not at all if /dev/tty exists and is a character device.
* Replace all occurrences of /dev/tty with another tty in case
  /dev/tty does not exist, but others do.
* Disable the test for zsh's -c completely if no tty at all is
  available as to be tested character device.

1 files changed, 48 insertions, 0 deletions

diff --git a/debian/patch-test-suite.sh b/debian/patch-test-suite.sh
new file mode 100755
index 000000000..9e46ae4d2
--- /dev/null
+++ b/debian/patch-test-suite.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+
+set -e
+
+TEST=Test/C02cond.ztst
+
+if [ "$1" = "--reverse" ]; then
+    TTY="$2"
+
+    # Unpatch
+    if [ "$TTY" = "/dev/tty" ]; then
+        exit 0;
+    elif [ -n "$TTY" ]; then
+        echo "Replacing $TTY with /dev/tty in $TEST"
+        sed -e "s:$TTY:/dev/tty:" -i $TEST || true
+    else
+        echo "Patch back in that check that needs /dev/tty. (Failures are ok.)"
+        patch -R -f --no-backup-if-mismatch -F0 -r- -s -p1 < debian/patches/disable-tests-which-need-dev-tty.patch || true
+    fi
+else
+    TTY="$1"
+
+    if [ "$TTY" = "/dev/tty" ]; then
+        # Sanity check
+        if [ -c /dev/tty ]; then
+            echo "/dev/tty exists and is a character device, hence no patching needed."
+            exit 0;
+        else
+
+            echo "$MAKE's -c test in debian/rules said /dev/tty is"
+            echo "a character device, but $0's checks says it's not:"
+            ls -l /dev/tty
+            exit 1
+        fi
+    elif [ -n "$TTY" ]; then
+        echo "Replacing /dev/tty with $TTY in $TEST"
+        sed -e "s:/dev/tty:$TTY:" -i $TEST
+    else
+        echo "Huh? No character device named tty* found at all in /dev/"
+        # Reality check
+        find /dev/ -name 'tty*' -type c || true
+
+        echo "Well, then let's patch out that check that needs"
+        echo "/dev/tty to be a character device."
+
+        patch -f --no-backup-if-mismatch -F0 -r- -s -p1 < debian/patches/disable-tests-which-need-dev-tty.patch
+    fi
+fi