hust_test/*: use "$THIS_SH" instead of hush

diff --git a/shell/hush_test/hush-trap/catch.tests b/shell/hush_test/hush-trap/catch.tests
index b1a4ed9..d2a21d1 100755
--- a/shell/hush_test/hush-trap/catch.tests
+++ b/shell/hush_test/hush-trap/catch.tests
@@ -1,7 +1,7 @@
 # avoid ugly warnings about signals not being caught
 trap ":" USR1 USR2
 
-hush -c '
+"$THIS_SH" -c '
 trap "echo caught" USR2
 echo "sending USR2"
 kill -USR2 $$
diff --git a/shell/hush_test/hush-trap/exit.tests b/shell/hush_test/hush-trap/exit.tests
index 174e74f..092543c 100755
--- a/shell/hush_test/hush-trap/exit.tests
+++ b/shell/hush_test/hush-trap/exit.tests
@@ -1,3 +1,3 @@
-hush -c 'trap "echo cow" 0'
-hush -c 'trap "echo moo" EXIT'
-hush -c 'trap "echo no" 0; trap 0'
+"$THIS_SH" -c 'trap "echo cow" 0'
+"$THIS_SH" -c 'trap "echo moo" EXIT'
+"$THIS_SH" -c 'trap "echo no" 0; trap 0'
diff --git a/shell/hush_test/hush-vars/param_expand_alt.tests b/shell/hush_test/hush-vars/param_expand_alt.tests
index c46075b..dcdca86 100755
--- a/shell/hush_test/hush-vars/param_expand_alt.tests
+++ b/shell/hush_test/hush-vars/param_expand_alt.tests
@@ -1,6 +1,6 @@
 # first try some invalid patterns (do in subshell due to parsing error)
-hush -c 'echo ${+}  ; echo moo'
-hush -c 'echo ${:+} ; echo moo'
+"$THIS_SH" -c 'echo ${+}  ; echo moo'
+"$THIS_SH" -c 'echo ${:+} ; echo moo'
 
 # now some funky ones
 echo _${#+} _${#:+}
diff --git a/shell/hush_test/hush-vars/param_expand_assign.tests b/shell/hush_test/hush-vars/param_expand_assign.tests
index 1fba556..149cb20 100755
--- a/shell/hush_test/hush-vars/param_expand_assign.tests
+++ b/shell/hush_test/hush-vars/param_expand_assign.tests
@@ -1,22 +1,22 @@
 # first try some invalid patterns (do in subshell due to parsing error)
-hush -c 'echo ${=}'
-hush -c 'echo ${:=}'
+"$THIS_SH" -c 'echo ${=}'
+"$THIS_SH" -c 'echo ${:=}'
 
 # now some funky ones
-hush -c 'echo ${#=}'
-hush -c 'echo ${#:=}'
+"$THIS_SH" -c 'echo ${#=}'
+"$THIS_SH" -c 'echo ${#:=}'
 
 # should error out
-hush -c 'set --; echo _${1=}'
-hush -c 'set --; echo _${1:=}'
-hush -c 'set --; echo _${1=word}'
-hush -c 'set --; echo _${1:=word}'
+"$THIS_SH" -c 'set --; echo _${1=}'
+"$THIS_SH" -c 'set --; echo _${1:=}'
+"$THIS_SH" -c 'set --; echo _${1=word}'
+"$THIS_SH" -c 'set --; echo _${1:=word}'
 
 # should not error
-hush -c 'set aa; echo _${1=}'
-hush -c 'set aa; echo _${1:=}'
-hush -c 'set aa; echo _${1=word}'
-hush -c 'set aa; echo _${1:=word}'
+"$THIS_SH" -c 'set aa; echo _${1=}'
+"$THIS_SH" -c 'set aa; echo _${1:=}'
+"$THIS_SH" -c 'set aa; echo _${1=word}'
+"$THIS_SH" -c 'set aa; echo _${1:=word}'
 
 # should work fine
 unset f; echo _$f
diff --git a/shell/hush_test/hush-vars/param_expand_default.tests b/shell/hush_test/hush-vars/param_expand_default.tests
index 2320ece..1ea0517 100755
--- a/shell/hush_test/hush-vars/param_expand_default.tests
+++ b/shell/hush_test/hush-vars/param_expand_default.tests
@@ -1,6 +1,6 @@
 # first try some invalid patterns (do in subshell due to parsing error)
-hush -c 'echo ${-}'
-hush -c 'echo ${:-}'
+"$THIS_SH" -c 'echo ${-}'
+"$THIS_SH" -c 'echo ${:-}'
 
 # now some funky ones
 echo _${#-} _${#:-}
diff --git a/shell/hush_test/hush-vars/param_expand_indicate_error.tests b/shell/hush_test/hush-vars/param_expand_indicate_error.tests
index 6b431d3..77834fe 100755
--- a/shell/hush_test/hush-vars/param_expand_indicate_error.tests
+++ b/shell/hush_test/hush-vars/param_expand_indicate_error.tests
@@ -1,40 +1,40 @@
 # do all of these in subshells since it's supposed to error out
 
 # first try some invalid patterns
-hush -c 'echo ${?}'
-hush -c 'echo ${:?}'
+"$THIS_SH" -c 'echo ${?}'
+"$THIS_SH" -c 'echo ${:?}'
 
 # then some funky ones
-hush -c 'echo ${#?}'
-hush -c 'echo ${#:?}'
+"$THIS_SH" -c 'echo ${#?}'
+"$THIS_SH" -c 'echo ${#:?}'
 
 # now some valid ones
-hush -c 'set --; echo _$1'
-hush -c 'set --; echo _${1?}'
-hush -c 'set --; echo _${1:?}'
-hush -c 'set --; echo _${1?word}'
-hush -c 'set --; echo _${1:?word}'
+"$THIS_SH" -c 'set --; echo _$1'
+"$THIS_SH" -c 'set --; echo _${1?}'
+"$THIS_SH" -c 'set --; echo _${1:?}'
+"$THIS_SH" -c 'set --; echo _${1?word}'
+"$THIS_SH" -c 'set --; echo _${1:?word}'
 
-hush -c 'set -- aaaa; echo _$1'
-hush -c 'set -- aaaa; echo _${1?}'
-hush -c 'set -- aaaa; echo _${1:?}'
-hush -c 'set -- aaaa; echo _${1?word}'
-hush -c 'set -- aaaa; echo _${1:?word}'
+"$THIS_SH" -c 'set -- aaaa; echo _$1'
+"$THIS_SH" -c 'set -- aaaa; echo _${1?}'
+"$THIS_SH" -c 'set -- aaaa; echo _${1:?}'
+"$THIS_SH" -c 'set -- aaaa; echo _${1?word}'
+"$THIS_SH" -c 'set -- aaaa; echo _${1:?word}'
 
-hush -c 'unset f; echo _$f'
-hush -c 'unset f; echo _${f?}'
-hush -c 'unset f; echo _${f:?}'
-hush -c 'unset f; echo _${f?word}'
-hush -c 'unset f; echo _${f:?word}'
+"$THIS_SH" -c 'unset f; echo _$f'
+"$THIS_SH" -c 'unset f; echo _${f?}'
+"$THIS_SH" -c 'unset f; echo _${f:?}'
+"$THIS_SH" -c 'unset f; echo _${f?word}'
+"$THIS_SH" -c 'unset f; echo _${f:?word}'
 
-hush -c 'f=; echo _$f'
-hush -c 'f=; echo _${f?}'
-hush -c 'f=; echo _${f:?}'
-hush -c 'f=; echo _${f?word}'
-hush -c 'f=; echo _${f:?word}'
+"$THIS_SH" -c 'f=; echo _$f'
+"$THIS_SH" -c 'f=; echo _${f?}'
+"$THIS_SH" -c 'f=; echo _${f:?}'
+"$THIS_SH" -c 'f=; echo _${f?word}'
+"$THIS_SH" -c 'f=; echo _${f:?word}'
 
-hush -c 'f=fff; echo _$f'
-hush -c 'f=fff; echo _${f?}'
-hush -c 'f=fff; echo _${f:?}'
-hush -c 'f=fff; echo _${f?word}'
-hush -c 'f=fff; echo _${f:?word}'
+"$THIS_SH" -c 'f=fff; echo _$f'
+"$THIS_SH" -c 'f=fff; echo _${f?}'
+"$THIS_SH" -c 'f=fff; echo _${f:?}'
+"$THIS_SH" -c 'f=fff; echo _${f?word}'
+"$THIS_SH" -c 'f=fff; echo _${f:?word}'
diff --git a/shell/hush_test/hush-vars/var3.tests b/shell/hush_test/hush-vars/var3.tests
index 2947fcc..e09f433 100755
--- a/shell/hush_test/hush-vars/var3.tests
+++ b/shell/hush_test/hush-vars/var3.tests
@@ -1,4 +1,4 @@
 # reject invalid vars
-hush -c 'echo ${1q}'
-hush -c 'echo ${&}'
-hush -c 'echo ${$}'
+"$THIS_SH" -c 'echo ${1q}'
+"$THIS_SH" -c 'echo ${&}'
+"$THIS_SH" -c 'echo ${$}'