diff --git a/tests/synclines.at b/tests/synclines.at
index 362fc73d..b76e47ab 100644
--- a/tests/synclines.at
+++ b/tests/synclines.at
@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-AT_BANNER([[User Actions.]])
+AT_BANNER([[Sync Lines.]])
 
 
 # _AT_SYNCLINES_COMPILE(FILE)
@@ -184,9 +184,11 @@ AT_CLEANUP
 AT_TEST([Prologue syncline],
 [[%{
 #error "2"
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
 %}
+%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
 %%
 exp: '0';
 %%
@@ -204,10 +206,10 @@ AT_TEST([%union syncline],
 #error "2"
   char dummy;
 }
-%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
-%}
+%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
 %%
 exp: '0';
 %%
@@ -229,9 +231,9 @@ AT_DATA([[input.y]],
 {
   char dummy;
 }
-%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
+%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
 %}
 %%
 exp: '0';
@@ -250,22 +252,25 @@ AT_CLEANUP
 ## ----------------------- ##
 
 AT_TEST([Postprologue syncline],
-[[%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
+[[%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
+%{
+  /* Preprologue.  */
 %}
 %union
 {
   int ival;
 }
 %{
-#error "10"
+#error "13"
 %}
 %%
 exp: '0';
 %%
 ]],
-[input.y:10: #error "10"
+[input.y:13: #error "13"
 ])
 
 
@@ -274,10 +279,10 @@ exp: '0';
 ## ----------------- ##
 
 AT_TEST([Action syncline],
-[[%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
-%}
+[[%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
 %%
 exp:
 {
@@ -293,10 +298,10 @@ exp:
 ## ------------------- ##
 
 AT_TEST([Epilogue syncline],
-[[%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
-%}
+[[%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
 %%
 exp: '0';
 %%
@@ -313,10 +318,10 @@ AT_TEST([%code top syncline],
 [[%code top {
 #error "2"
 }
-%{
-]AT_YYERROR_DECLARE_EXTERN[
-]AT_YYLEX_DECLARE_EXTERN[
-%}
+%code {
+  ]AT_YYERROR_DECLARE_EXTERN[
+  ]AT_YYLEX_DECLARE_EXTERN[
+}
 %%
 exp: '0';
 %%
@@ -324,25 +329,27 @@ exp: '0';
 [input.y:2: #error "2"
 ])
 
-m4_popdef([AT_TEST])
+
 
 ## ----------- ##
 ## %no-lines.  ##
 ## ----------- ##
 
+# AT_TEST([SKELETON])
+# -------------------
 m4_pushdef([AT_TEST],
 [AT_SETUP([%no-lines: $1])
 
 AT_BISON_OPTION_PUSHDEFS([%skeleton "$1" %defines])
 AT_DATA_GRAMMAR([input.y],
-[%skeleton "$1" %defines
+[[%skeleton "$1" %defines
 %{
 ]AT_YYERROR_DECLARE_EXTERN[
 ]AT_YYLEX_DECLARE_EXTERN[
 %}
 %%
 exp: '0'
-])
+]])
 AT_BISON_CHECK([--no-lines -o input.AT_SKEL_CC_IF([cc], [c]) -d input.y])
 AT_CHECK([[grep '#line' ]AT_SKEL_CC_IF([*.cc *.hh], [*.c *.h])], 1)
 AT_BISON_OPTION_POPDEFS