b2/test/: add first set of substitution tests

b2/test/subvar

@@ -0,0 +1,88 @@
+#!/bin/bash
+. ./Common
+
+###############################################################################
+
+tst "substitutions: variable expansion $FOO" -ds -q <<EOF
+!-s
+FOO=x
+BAR = \$FOO
+EOF
+
+expect <<EOF
+FOO=x
+BAR=\${FOO}
+FOO=x
+BAR=x
+EOF
+
+#------------------------------------------------------------------------------
+
+tst "substitutions: variable expansion ${FOO}bar" -ds -q <<EOF
+!-s
+FOO=x
+BAR = \${FOO}bar
+EOF
+
+expect <<EOF
+FOO=x
+BAR=\${FOO}bar
+FOO=x
+BAR=xbar
+EOF
+
+#------------------------------------------------------------------------------
+
+tst_fail "substitutions: expand unknown variable" -ds <<EOF
+!-s
+BAR = \${FOO}
+EOF
+
+expect <<EOF
+s:2: \$FOO may be undefined
+EOF
+
+#------------------------------------------------------------------------------
+
+tst "substitutions: expand variable used in match" -ds -q FOO=blah <<EOF
+!-s
+FOO = * { BAR = \$FOO }
+EOF
+
+expect <<EOF
+FOO=RE {
+    BAR=\${FOO}
+}
+BAR=blah
+EOF
+
+#------------------------------------------------------------------------------
+
+tst_fail "substitutions: expand variable used in different branch" -ds <<EOF
+!-s
+FOO = * { BAR = \$FOO }
+FOO = \$BAR
+EOF
+
+expect <<EOF
+s:3: \$BAR may be undefined
+EOF
+
+#------------------------------------------------------------------------------
+
+tst "substitutions: expand two variables" -ds -q <<EOF
+!-s
+FOO = a
+BAR = b
+FOO = \$FOO\$BAR
+EOF
+
+expect <<EOF
+FOO=a
+BAR=b
+FOO=\${FOO}\${BAR}
+FOO=ab
+BAR=b
+EOF
+
+###############################################################################