partial cherry-pick of d4507ec6 to import assertion functions

tests/support/test.tcl

@@ -2,7 +2,38 @@ set ::passed 0
 set ::failed 0
 set ::testnum 0
 
-proc test {name code okpattern} {
+proc assert_match {pattern value} {
+    if {![string match $pattern $value]} {
+        puts "!! ERROR\nExpected '$value' to match '$pattern'"
+        error "assertion"
+    }
+}
+
+proc assert_equal {expected value} {
+    if {$expected ne $value} {
+        puts "!! ERROR\nExpected '$value' to be equal to '$expected'"
+        error "assertion"
+    }
+}
+
+proc assert_error {pattern code} {
+    if {[catch $code error]} {
+        assert_match $pattern $error
+    } else {
+        puts "!! ERROR\nExpected an error but nothing was catched"
+        error "assertion"
+    }
+}
+
+proc assert_encoding {enc key} {
+    assert_match "* encoding:$enc *" [r debug object $key]
+}
+
+proc assert_type {type key} {
+    assert_equal $type [r type $key]
+}
+
+proc test {name code {okpattern notspecified}} {
     # abort if tagged with a tag to deny
     foreach tag $::denytags {
         if {[lsearch $::tags $tag] >= 0} {
@@ -28,17 +59,22 @@ proc test {name code okpattern} {
     puts -nonewline [format "#%03d %-68s " $::testnum $name]
     flush stdout
     if {[catch {set retval [uplevel 1 $code]} error]} {
+        if {$error eq "assertion"} {
+            incr ::failed
+        } else {
             puts "EXCEPTION"
             puts "\nCaught error: $error"
             error "exception"
         }
-    if {$okpattern eq $retval || [string match $okpattern $retval]} {
+    } else {
+        if {$okpattern eq "notspecified" || $okpattern eq $retval || [string match $okpattern $retval]} {
             puts "PASSED"
             incr ::passed
         } else {
             puts "!! ERROR expected\n'$okpattern'\nbut got\n'$retval'"
             incr ::failed
         }
+    }
     if {$::traceleaks} {
         if {![string match {*0 leaks*} [exec leaks redis-server]]} {
             puts "--------- Test $::testnum LEAKED! --------"