Fix msg argument to assert_equal

I noticed this was taking an argument but not dealing with it.  In
general the functions were undocumented, so I added some terse usage.

Also, the intent of the test-case was to expand the values before
using them as the message; make sure this happens by using a temp
variable.

Change-Id: Ib317ad1e9dd2a5d2232b9c64541fe4a601a2b8da

Author: ianw

tests/test_truefalse.sh

@@ -19,7 +19,8 @@ function test_trueorfalse {
 
     for default in True False; do
         for name in one captrue lowtrue uppertrue capyes lowyes upperyes; do
-                assert_equal "True" $(trueorfalse $default $name) "\$(trueorfalse $default $name)"
+            local msg="trueorfalse($default $name)"
+            assert_equal "True" $(trueorfalse $default $name) "$msg"
         done
     done
 
@@ -33,7 +34,8 @@ function test_trueorfalse {
 
     for default in True False; do
         for name in zero capfalse lowfalse upperfalse capno lowno upperno; do
-            assert_equal "False" $(trueorfalse $default $name) "\$(trueorfalse $default $name)"
+            local msg="trueorfalse($default $name)"
+            assert_equal "False" $(trueorfalse $default $name) "$msg"
         done
     done
 }

tests/unittest.sh

@@ -17,6 +17,8 @@ ERROR=0
 PASS=0
 FAILED_FUNCS=""
 
+# pass a test, printing out MSG
+#  usage: passed message
 function passed {
     local lineno=$(caller 0 | awk '{print $1}')
     local function=$(caller 0 | awk '{print $2}')
@@ -25,9 +27,11 @@ function passed {
         msg="OK"
     fi
     PASS=$((PASS+1))
-    echo $function:L$lineno $msg
+    echo "PASS: $function:L$lineno $msg"
 }
 
+# fail a test, printing out MSG
+#  usage: failed message
 function failed {
     local lineno=$(caller 0 | awk '{print $1}')
     local function=$(caller 0 | awk '{print $2}')
@@ -38,21 +42,30 @@ function failed {
     ERROR=$((ERROR+1))
 }
 
+# assert string comparision of val1 equal val2, printing out msg
+#  usage: assert_equal val1 val2 msg
 function assert_equal {
     local lineno=`caller 0 | awk '{print $1}'`
     local function=`caller 0 | awk '{print $2}'`
     local msg=$3
+
+    if [ -z "$msg" ]; then
+        msg="OK"
+    fi
     if [[ "$1" != "$2" ]]; then
         FAILED_FUNCS+="$function:L$lineno\n"
         echo "ERROR: $1 != $2 in $function:L$lineno!"
         echo "  $msg"
         ERROR=$((ERROR+1))
     else
         PASS=$((PASS+1))
-        echo "$function:L$lineno - ok"
+        echo "PASS: $function:L$lineno - $msg"
     fi
 }
 
+# print a summary of passing and failing tests, exiting
+# with an error if we have failed tests
+#  usage: report_results
 function report_results {
     echo "$PASS Tests PASSED"
     if [[ $ERROR -gt 1 ]]; then