patch 8.2.0493: Vim9: some error messages not tested

Problem:    Vim9: some error messages not tested.
Solution:   Add more tests.  Fix uncovered bugs.

runtime/doc/eval.txt

@@ -2861,6 +2861,7 @@ test_ignore_error({expr})	none	ignore a specific error
 test_null_blob()		Blob	null value for testing
 test_null_channel()		Channel	null value for testing
 test_null_dict()		Dict	null value for testing
+test_null_function()		Funcref	null value for testing
 test_null_job()			Job	null value for testing
 test_null_list()		List	null value for testing
 test_null_partial()		Funcref	null value for testing

runtime/doc/testing.txt

@@ -106,6 +106,10 @@ test_null_dict()					*test_null_dict()*
 		Return a |Dict| that is null. Only useful for testing.
 
 
+test_null_function()					*test_null_function()*
+		Return a |FuncRef| that is null. Only useful for testing.
+
+
 test_null_job()						*test_null_job()*
 		Return a |Job| that is null. Only useful for testing.
 		{only available when compiled with the +job feature}

src/eval.c

@@ -3849,8 +3849,12 @@ tv_equal(
 	    return tv1->vval.v_channel == tv2->vval.v_channel;
 #endif
 
-	case VAR_FUNC:
 	case VAR_PARTIAL:
+	    return tv1->vval.v_partial == tv2->vval.v_partial;
+
+	case VAR_FUNC:
+	    return tv1->vval.v_string == tv2->vval.v_string;
+
 	case VAR_UNKNOWN:
 	case VAR_VOID:
 	    break;

src/evalfunc.c

@@ -290,7 +290,8 @@ ret_string(int argcount UNUSED, type_T **argtypes UNUSED)
 {
     return &t_string;
 }
-    static type_T * ret_list_any(int argcount UNUSED, type_T **argtypes UNUSED)
+    static type_T *
+ret_list_any(int argcount UNUSED, type_T **argtypes UNUSED)
 {
     return &t_list_any;
 }
@@ -330,9 +331,14 @@ ret_blob(int argcount UNUSED, type_T **argtypes UNUSED)
     return &t_blob;
 }
     static type_T *
-ret_partial_void(int argcount UNUSED, type_T **argtypes UNUSED)
+ret_func_any(int argcount UNUSED, type_T **argtypes UNUSED)
 {
-    return &t_partial_void;
+    return &t_func_any;
+}
+    static type_T *
+ret_partial_any(int argcount UNUSED, type_T **argtypes UNUSED)
+{
+    return &t_partial_any;
 }
     static type_T *
 ret_channel(int argcount UNUSED, type_T **argtypes UNUSED)
@@ -558,7 +564,7 @@ static funcentry_T global_functions[] =
     {"foldtext",	0, 0, 0,	  ret_string,	f_foldtext},
     {"foldtextresult",	1, 1, FEARG_1,	  ret_string,	f_foldtextresult},
     {"foreground",	0, 0, 0,	  ret_void,	f_foreground},
-    {"funcref",		1, 3, FEARG_1,	  ret_partial_void, f_funcref},
+    {"funcref",		1, 3, FEARG_1,	  ret_partial_any, f_funcref},
     {"function",	1, 3, FEARG_1,	  ret_f_function, f_function},
     {"garbagecollect",	0, 1, 0,	  ret_void,	f_garbagecollect},
     {"get",		2, 3, FEARG_1,	  ret_any,	f_get},
@@ -952,9 +958,10 @@ static funcentry_T global_functions[] =
     {"test_null_blob",	0, 0, 0,	  ret_blob,	f_test_null_blob},
     {"test_null_channel", 0, 0, 0,	  ret_channel,	JOB_FUNC(f_test_null_channel)},
     {"test_null_dict",	0, 0, 0,	  ret_dict_any,	f_test_null_dict},
+    {"test_null_function", 0, 0, 0,	  ret_func_any,	f_test_null_function},
     {"test_null_job",	0, 0, 0,	  ret_job,	JOB_FUNC(f_test_null_job)},
     {"test_null_list",	0, 0, 0,	  ret_list_any,	f_test_null_list},
-    {"test_null_partial", 0, 0, 0,	  ret_partial_void, f_test_null_partial},
+    {"test_null_partial", 0, 0, 0,	  ret_partial_any, f_test_null_partial},
     {"test_null_string", 0, 0, 0,	  ret_string,	f_test_null_string},
     {"test_option_not_set", 1, 1, FEARG_1,ret_void,	 f_test_option_not_set},
     {"test_override",	2, 2, FEARG_2,	  ret_void,	f_test_override},

src/proto/testing.pro

@@ -26,6 +26,7 @@ void f_test_null_channel(typval_T *argvars, typval_T *rettv);
 void f_test_null_dict(typval_T *argvars, typval_T *rettv);
 void f_test_null_job(typval_T *argvars, typval_T *rettv);
 void f_test_null_list(typval_T *argvars, typval_T *rettv);
+void f_test_null_function(typval_T *argvars, typval_T *rettv);
 void f_test_null_partial(typval_T *argvars, typval_T *rettv);
 void f_test_null_string(typval_T *argvars, typval_T *rettv);
 void f_test_unknown(typval_T *argvars, typval_T *rettv);

src/testdir/test_vim9_script.vim

@@ -117,6 +117,48 @@ def Test_assignment()
   assert_equal('aregadd', @a)
   call CheckDefFailure(['@a += "more"'], 'E1013:')
   call CheckDefFailure(['@a += 123'], 'E1013:')
+
+  v:errmsg = 'none'
+  v:errmsg ..= 'again'
+  assert_equal('noneagain', v:errmsg)
+  call CheckDefFailure(['v:errmsg += "more"'], 'E1013:')
+  call CheckDefFailure(['v:errmsg += 123'], 'E1013:')
+
+  " Test default values.
+  let thebool: bool
+  assert_equal(v:false, thebool)
+
+  let thenumber: number
+  assert_equal(0, thenumber)
+
+  if has('float')
+    let thefloat: float
+    assert_equal(0.0, thefloat)
+  endif
+
+  let thestring: string
+  assert_equal('', thestring)
+
+  let theblob: blob
+  assert_equal(0z, theblob)
+
+  let thefunc: func
+  assert_equal(test_null_function(), thefunc)
+
+  let thepartial: partial
+  assert_equal(test_null_partial(), thepartial)
+
+  let thelist: list<any>
+  assert_equal([], thelist)
+
+  let thedict: dict<any>
+  assert_equal({}, thedict)
+
+  let thejob: job
+  assert_equal(test_null_job(), thejob)
+
+  let thechannel: channel
+  assert_equal(test_null_channel(), thechannel)
 enddef
 
 func Test_assignment_failure()
@@ -129,6 +171,7 @@ func Test_assignment_failure()
 
   call CheckDefFailure(['let [a; b; c] = g:list'], 'E452:')
 
+  call CheckDefFailure(['let somevar'], "E1022:")
   call CheckDefFailure(['let &option'], 'E1052:')
   call CheckDefFailure(['&g:option = 5'], 'E113:')
 

src/testing.c

@@ -882,6 +882,13 @@ f_test_null_list(typval_T *argvars UNUSED, typval_T *rettv)
     rettv_list_set(rettv, NULL);
 }
 
+    void
+f_test_null_function(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    rettv->v_type = VAR_FUNC;
+    rettv->vval.v_string = NULL;
+}
+
     void
 f_test_null_partial(typval_T *argvars UNUSED, typval_T *rettv)
 {

src/version.c

@@ -738,6 +738,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    493,
 /**/
     492,
 /**/

src/vim9compile.c

@@ -766,7 +766,7 @@ generate_PUSHFUNC(cctx_T *cctx, char_u *name)
 
 /*
  * Generate an ISN_PUSHPARTIAL instruction with partial "part".
- * Consumes "name".
+ * Consumes "part".
  */
     static int
 generate_PUSHPARTIAL(cctx_T *cctx, partial_T *part)
@@ -3808,9 +3808,6 @@ compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
 	    case VAR_BOOL:
 		generate_PUSHBOOL(cctx, VVAL_FALSE);
 		break;
-	    case VAR_SPECIAL:
-		generate_PUSHSPEC(cctx, VVAL_NONE);
-		break;
 	    case VAR_FLOAT:
 #ifdef FEAT_FLOAT
 		generate_PUSHF(cctx, 0.0);
@@ -3843,6 +3840,7 @@ compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
 	    case VAR_NUMBER:
 	    case VAR_UNKNOWN:
 	    case VAR_VOID:
+	    case VAR_SPECIAL:  // cannot happen
 		generate_PUSHNR(cctx, 0);
 		break;
 	}

src/vim9execute.c

@@ -920,7 +920,9 @@ call_def_function(
 			break;
 		    default:
 			tv->v_type = VAR_STRING;
-			tv->vval.v_string = vim_strsave(iptr->isn_arg.string);
+			tv->vval.v_string = vim_strsave(
+				iptr->isn_arg.string == NULL
+					? (char_u *)"" : iptr->isn_arg.string);
 		}
 		break;