minor tweaks to setx

src/zcl_ajson.clas.abap

@@ -675,6 +675,7 @@ CLASS ZCL_AJSON IMPLEMENTATION.
     data lv_last type i.
 
     if iv_param is initial.
+      ri_json = me.
       return.
     endif.
 
@@ -683,6 +684,7 @@ CLASS ZCL_AJSON IMPLEMENTATION.
     condense lv_val.
 
     if lv_val is initial.
+      ri_json = me.
       return. " Hmm ? or empty string ? or null ?
     endif.
 

src/zcl_ajson.clas.testclasses.abap

@@ -3124,13 +3124,23 @@ class ltcl_writer_test implementation.
 
     cl_abap_unit_assert=>assert_equals(
       act = zcl_ajson=>new( )->setx( '/:1' )->stringify( )
-      exp = '1' ). " Hmmm ?
+      exp = '1' ). " Because set( path = '/' ) would write root node
 
     cl_abap_unit_assert=>assert_equals(
       act = zcl_ajson=>new( )->setx( ':1' )->stringify( )
-      exp = '1' ). " Hmmm ?
+      exp = '1' ). " Because set( path = '' ) would write root node
 
-    " TODO some negative tests like "/a:", ""
+*    cl_abap_unit_assert=>assert_equals(
+*      act = zcl_ajson=>new( )->setx( '' )->stringify( )
+*      exp = '{}' ). " problem is that root node not set so it is not an object
+
+*    cl_abap_unit_assert=>assert_equals(
+*      act = zcl_ajson=>new( )->setx( '/a:' )->stringify( )
+*      exp = '{}' ). " should setx ignore empty values or set an empty string ? Or null ?
+
+    cl_abap_unit_assert=>assert_equals(
+      act = zcl_ajson=>new( )->setx( '/a:""' )->stringify( )
+      exp = '{"a":""}' ).
 
   endmethod.
 
@@ -3142,7 +3152,7 @@ class ltcl_writer_test implementation.
 
     cl_abap_unit_assert=>assert_equals(
       act = zcl_ajson=>new( )->setx( '/a:00.123' )->stringify( )
-      exp = '{"a":"00.123"}' ). " hmmm
+      exp = '{"a":"00.123"}' ). " not a number
 
     cl_abap_unit_assert=>assert_equals(
       act = zcl_ajson=>new( )->setx( '/a:.123' )->stringify( )