Index: common.scm
==================================================================
--- common.scm
+++ common.scm
@@ -791,20 +791,24 @@
 
 (define (common:args-get-status)
   (or (args:get-arg "-status")(args:get-arg ":status")))
 
 (define (common:args-get-testpatt rconf)
-  (let* ((rtestpatt     (if rconf (runconfigs-get rconf "TESTPATT") #f))
-	 (args-testpatt (or (args:get-arg "-testpatt")
-			    (args:get-arg "-runtests")
-			    "%"))
-	 (testpatt    (or (and (equal? args-testpatt "%")
-			       rtestpatt)
-			  args-testpatt)))
-    (if rtestpatt (debug:print-info 0 *default-log-port* "TESTPATT from runconfigs: " rtestpatt))
-    testpatt))
-
+  (let* ((tagexpr (args:get-arg "-tagexpr"))
+         (tags-testpatt (if tagexpr (string-join (runs:get-tests-matching-tags tagexpr) ",") #f))
+         (testpatt-key  (if (args:get-arg "-mode") (args:get-arg "-mode") "TESTPATT"))
+         (args-testpatt (or (args:get-arg "-testpatt") (args:get-arg "-runtests") "%"))
+         (rtestpatt     (if rconf (runconfigs-get rconf testpatt-key) #f)))
+    (cond
+     (tags-testpatt
+      (debug:print-info 0 *default-log-port* "-tagexpr "tagexpr" selects testpatt "tags-testpatt)
+      tags-testpatt)
+     ((and (equal? args-testpatt "%") rtestpatt)
+      (debug:print-info 0 *default-log-port* "testpatt defined in "testpatt-key" from runconfigs: " rtestpatt)
+      rtestpatt)
+     (else args-testpatt))))
+     
 (define (common:get-linktree)
   (or (getenv "MT_LINKTREE")
       (if *configdat*
 	  (configf:lookup *configdat* "setup" "linktree"))))
 

Index: megatest.scm
==================================================================
--- megatest.scm
+++ megatest.scm
@@ -93,10 +93,12 @@
   -reqtarg key1/key2/...  : run for key1, key2, etc. but key1/key2 must be in runconfig
   -testpatt patt1/patt2,patt3/...  : % is wildcard
   -runname                : required, name for this particular test run
   -state                  : Applies to runs, tests or steps depending on context
   -status                 : Applies to runs, tests or steps depending on context
+  -mode key               : load testpatt from <key> in runconfigs instead of default TESTPATT
+  -tagexpr tag1,tag2%,..  : select tests with tags matching expression
 
 Test helpers (for use inside tests)
   -step stepname
   -test-status            : set the state and status of a test (use :state and :status)
   -setlog logfname        : set the path/filename to the final log relative to the test
@@ -209,11 +211,13 @@
 			":state"  
 			"-state"
 			":status"
 			"-status"
 			"-list-runs"
-			"-testpatt" 
+			"-testpatt"
+                        "-mode"
+                        "-tagexpr"
 			"-itempatt"
 			"-setlog"
 			"-set-toplog"
 			"-runstep"
 			"-logpro"