shell/math: fix order of expansion of variables to numbers

This fixes arith-assign-in-varexp1.tests

function                                             old     new   delta
evaluate_string                                     1132    1258    +126
arith_lookup_val                                     143       -    -143
arith_apply                                         1132     977    -155
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 1/1 up/down: 126/-298)         Total: -172 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 11 insertions, 0 deletions

diff --git a/shell/hush_test/hush-arith/arith-assign-in-varexp1.right b/shell/hush_test/hush-arith/arith-assign-in-varexp1.right
new file mode 100644
index 0000000..1feb307
--- /dev/null
+++ b/shell/hush_test/hush-arith/arith-assign-in-varexp1.right
@@ -0,0 +1,2 @@
+7:7
+x=3
diff --git a/shell/hush_test/hush-arith/arith-assign-in-varexp1.tests b/shell/hush_test/hush-arith/arith-assign-in-varexp1.tests
new file mode 100755
index 0000000..fc8ac9d
--- /dev/null
+++ b/shell/hush_test/hush-arith/arith-assign-in-varexp1.tests
@@ -0,0 +1,9 @@
+exec 2>&1
+a='x=1'
+b='x=2'
+c='x=3'
+# The variables should evaluate immediately when they encountered,
+# not when they go into an operation. Here, order of evaluation
+# of names to numbers should be a,b,c - not b,c,a:
+echo 7:$((a+b*c))
+echo "x=$x"