update var_bash4 test. one more bug revealed by it now...

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/ash_test/ash-vars/var_bash4.right b/shell/ash_test/ash-vars/var_bash4.right
index fc3a9e4..2d4e45b 100644
--- a/shell/ash_test/ash-vars/var_bash4.right
+++ b/shell/ash_test/ash-vars/var_bash4.right
@@ -1,4 +1,23 @@
-In assignment: a*b-backslashstar-
-Unquoted: a*b-backslashstar-
-Quoted: a*b-backslashstar-
+Source:        a*b\*c
+Replace str:   _\\_\z_
+Pattern:       single backslash and star: "replace literal star"
+In assignment: a_\_z_b\*c
+Unquoted:      a_\_z_b\*c
+Quoted:        a_\_\z_b\*c
+Pattern:       double backslash and star: "replace backslash and everything after it"
+In assignment: a*b_\_z_
+Unquoted:      a*b_\_z_
+Quoted:        a*b_\_\z_
+
+Source:        a\bc
+Replace str:   _\\_\z_
+Pattern:       single backslash and b: "replace literal b"
+In assignment: a\_\_z_c
+Unquoted:      a\_\_z_c
+Quoted:        a\_\_\z_c
+Pattern:       double backslash and b: "replace backslash and b"
+In assignment: a_\_z_c
+Unquoted:      a_\_z_c
+Quoted:        a_\_\z_c
+
 Done: 0
diff --git a/shell/ash_test/ash-vars/var_bash4.tests b/shell/ash_test/ash-vars/var_bash4.tests
index 3b323c5..01a0def 100755
--- a/shell/ash_test/ash-vars/var_bash4.tests
+++ b/shell/ash_test/ash-vars/var_bash4.tests
@@ -1,6 +1,47 @@
-FOO='a*b\*c'
-BAR=${FOO//\\*/-backslashstar-}
-echo In assignment: "$BAR"
-echo Unquoted: ${FOO//\\*/-backslashstar-}
-echo Quoted: "${FOO//\\*/-backslashstar-}"
+# This testcase demonstrates that backslashes are treated differently
+# in 1st and 2nd parts of ${var/search/repl}:
+# if quoted: "${var/search/repl}", and repl contains \a (a non-special char),
+# the backslash in repl stays; if unquoted, backslash: removed
+# But search part does not act like that: \a is always converted to just a,
+# even in quotes.
+#
+# bash4 (and probably bash3 too) result: "Quoted:" results are different -
+# they have extra backslash before z.
+
+v='a*b\*c'
+echo 'Source:       ' "$v"
+echo 'Replace str:  ' '_\\_\z_'
+
+echo 'Pattern:      ' 'single backslash and star: "replace literal star"'
+r=${v/\*/_\\_\z_}
+echo 'In assignment:' "$r"
+echo 'Unquoted:     ' ${v/\*/_\\_\z_}
+echo 'Quoted:       ' "${v/\*/_\\_\z_}"
+
+echo 'Pattern:      ' 'double backslash and star: "replace backslash and everything after it"'
+r=${v/\\*/_\\_\z_}
+echo 'In assignment:' "$r"
+echo 'Unquoted:     '  ${v/\\*/_\\_\z_}
+echo 'Quoted:       ' "${v/\\*/_\\_\z_}"
+
+echo
+
+v='a\bc'
+echo 'Source:       ' "$v"
+echo 'Replace str:  ' '_\\_\z_'
+
+echo 'Pattern:      ' 'single backslash and b: "replace literal b"'
+r=${v/\b/_\\_\z_}
+echo 'In assignment:' "$r"
+echo 'Unquoted:     '  ${v/\b/_\\_\z_}
+echo 'Quoted:       ' "${v/\b/_\\_\z_}"
+
+echo 'Pattern:      ' 'double backslash and b: "replace backslash and b"'
+r=${v/\\b/_\\_\z_}
+echo 'In assignment:' "$r"
+echo 'Unquoted:     '  ${v/\\b/_\\_\z_}
+echo 'Quoted:       ' "${v/\\b/_\\_\z_}"
+
+echo
+
 echo Done: $?