diff --git a/testing/btest/broker/store/create-failure.zeek b/testing/btest/broker/store/create-failure.zeek
index 57f56b815c..0b0e2fbca0 100644
--- a/testing/btest/broker/store/create-failure.zeek
+++ b/testing/btest/broker/store/create-failure.zeek
@@ -46,7 +46,7 @@ function check_terminate_conditions()
 
 function check_it(name: string, s: opaque of Broker::Store)
 	{
-	when ( local r = Broker::keys(s) )
+	when [name, s] ( local r = Broker::keys(s) )
 		{
 		check_terminate_conditions();
 		print fmt("%s keys result: %s", name, r);
diff --git a/testing/btest/broker/store/invalid-handle.zeek b/testing/btest/broker/store/invalid-handle.zeek
index 3b270fa945..736962ba7b 100644
--- a/testing/btest/broker/store/invalid-handle.zeek
+++ b/testing/btest/broker/store/invalid-handle.zeek
@@ -8,7 +8,7 @@
 
 function print_keys(a: any)
 	{
-	when ( local s = Broker::keys(a) )
+	when [a] ( local s = Broker::keys(a) )
 		{
 		print "keys", s;
 		}
diff --git a/testing/btest/core/when-interpreter-exceptions.zeek b/testing/btest/core/when-interpreter-exceptions.zeek
index d9d37e7318..36d63396bb 100644
--- a/testing/btest/core/when-interpreter-exceptions.zeek
+++ b/testing/btest/core/when-interpreter-exceptions.zeek
@@ -37,7 +37,7 @@ function f(do_exception: bool): bool
 	local cmd = Exec::Command($cmd=fmt("echo 'f(%s)'",
 	                          do_exception));
 
-	return when ( local result = Exec::run(cmd) )
+	return when [cmd, do_exception] ( local result = Exec::run(cmd) )
 		{
 		print result$stdout;
 
@@ -58,7 +58,7 @@ function g(do_exception: bool): bool
 	{
 	local stall = Exec::Command($cmd="sleep 30");
 
-	return when ( local result = Exec::run(stall) )
+	return when [do_exception, stall] ( local result = Exec::run(stall) )
 		{
 		print "shouldn't get here, g()", do_exception, result;
 		}
@@ -84,14 +84,14 @@ event zeek_init()
 	local cmd = Exec::Command($cmd="echo 'zeek_init()'");
 	local stall = Exec::Command($cmd="sleep 30");
 
-	when ( local result = Exec::run(cmd) )
+	when [cmd] ( local result = Exec::run(cmd) )
 		{
 		print result$stdout;
 		event termination_check();
 		print myrecord$notset;
 		}
 
-	when ( local result2 = Exec::run(stall) )
+	when [stall] ( local result2 = Exec::run(stall) )
 		{
 		print "shouldn't get here", result2;
 		check_term_condition();
diff --git a/testing/btest/scripts/base/frameworks/sumstats/on-demand.zeek b/testing/btest/scripts/base/frameworks/sumstats/on-demand.zeek
index 208d9248f2..060552c0bd 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/on-demand.zeek
+++ b/testing/btest/scripts/base/frameworks/sumstats/on-demand.zeek
@@ -22,7 +22,7 @@ redef exit_only_after_terminate=T;
 event on_demand_key()
 	{
 	local host = 1.2.3.4;
-	when ( local result = SumStats::request_key("test", [$host=host]) )
+	when [host] ( local result = SumStats::request_key("test", [$host=host]) )
 		{
 		print fmt("Key request for %s", host);
 		print fmt("    Host: %s -> %.0f", host, result["test.reducer"]$sum);
diff --git a/testing/btest/scripts/base/utils/active-http.test b/testing/btest/scripts/base/utils/active-http.test
index b325bb40cc..d3fe3ebeac 100644
--- a/testing/btest/scripts/base/utils/active-http.test
+++ b/testing/btest/scripts/base/utils/active-http.test
@@ -23,7 +23,7 @@ function check_exit_condition()
 
 function test_request(label: string, req: ActiveHTTP::Request)
 	{
-	when ( local response = ActiveHTTP::request(req) )
+	when [label, req] ( local response = ActiveHTTP::request(req) )
 		{
 		print label, response;
 		check_exit_condition();
diff --git a/testing/btest/scripts/base/utils/exec.test b/testing/btest/scripts/base/utils/exec.test
index 80a98c8285..7cf64908ae 100644
--- a/testing/btest/scripts/base/utils/exec.test
+++ b/testing/btest/scripts/base/utils/exec.test
@@ -19,7 +19,7 @@ function check_exit_condition()
 
 function test_cmd(label: string, cmd: Exec::Command)
 	{
-	when ( local result = Exec::run(cmd) )
+	when [label, cmd] ( local result = Exec::run(cmd) )
 		{
 		local file_content = "";