typecheck: diagnose extra method args

README.md

@@ -180,6 +180,7 @@ CALL player.add WITH "five"
 ```text
 Type mismatch for method Player.add: parameter points needs NUMBER, but this argument looks like TEXT.
 Method Player.add needs argument points as NUMBER, but this call does not provide it.
+Method Player.add only accepts 1 argument, but this call gives 2. Remove the extra argument.
 ```
 
 If a learner calls a simple object method before creating the object with `NEW`, `claro typecheck` now points to the missing setup instead of letting the dotted call look like an ordinary unknown function. This covers both the modern `DO player.add 5` form and the older compatibility `CALL player.add WITH 5` form, including `CALL` mistakes where the method name itself is wrong:

docs/ADVANCED_STATIC_TYPING.md

@@ -152,7 +152,19 @@ Output:
 Method Player.add needs argument points as NUMBER, but this call does not provide it.
 ```
 
-Both sides of this narrow method foundation are covered by validation: `tests/typecheck_method_good.claro` checks that `DO player.add 5` is accepted, `tests/typecheck_method_bad.claro` checks the friendly wrong-type diagnostic, and `tests/typecheck_method_missing_arg_bad.claro` checks the missing checked-argument diagnostic.
+If the learner gives too many arguments to a simple checked method, `claro typecheck` now points to the extra argument instead of silently accepting it:
+
+```claro
+DO player.add 5, 6
+```
+
+Output:
+
+```text
+Method Player.add only accepts 1 argument, but this call gives 2. Remove the extra argument.
+```
+
+Both sides of this narrow method foundation are covered by validation: `tests/typecheck_method_good.claro` checks that `DO player.add 5` is accepted, `tests/typecheck_method_bad.claro` checks the friendly wrong-type diagnostic, `tests/typecheck_method_missing_arg_bad.claro` checks the missing checked-argument diagnostic, and `tests/typecheck_method_extra_arg_bad.claro` checks the extra-argument diagnostic.
 
 If the method call comes before the object is created, the type checker now gives the learner the missing setup step. The modern `DO` form and the older compatibility `CALL ... WITH` form both get this guidance, even when the method name is also a typo:
 

docs/CURRENT_STATUS.md

@@ -52,7 +52,7 @@ Ready now:
 - typed variables such as `SET score NUMBER 10`
 - `TYPE OF` and `CHECK TYPE`
 - typed list/map checks through `claro typecheck`
-- a narrow function/method argument check: `CHECK TYPE parameter IS TYPE` inside a function or simple object method lets `claro typecheck` accept correct checked calls, catch mismatched `DO`, `CALL ... WITH`, `DO object.method ...`, and compatibility `CALL object.method WITH ...` arguments, report missing checked function and method arguments, catch extra arguments to simple functions, explain when `DO object.method ...` or compatibility `CALL object.method WITH ...` happens before the object is created with `NEW` even if the method name is also wrong, and catch simple calls to undeclared methods with a class-specific `TEACH` hint
+- a narrow function/method argument check: `CHECK TYPE parameter IS TYPE` inside a function or simple object method lets `claro typecheck` accept correct checked calls, catch mismatched `DO`, `CALL ... WITH`, `DO object.method ...`, and compatibility `CALL object.method WITH ...` arguments, report missing checked function and method arguments, catch extra arguments to simple functions and checked methods, explain when `DO object.method ...` or compatibility `CALL object.method WITH ...` happens before the object is created with `NEW` even if the method name is also wrong, and catch simple calls to undeclared methods with a class-specific `TEACH` hint
 - a narrow object-field assignment/check-type check for simple `NEW Class object` plus direct `SET object.field value` and `CHECK TYPE object.field IS TYPE` cases when the class declares `HAS field TYPE`; validation now covers correct NUMBER, TEXT, and YESNO direct assignments, direct `CHECK TYPE` metadata acceptance for NUMBER/TEXT/YESNO fields, negative NUMBER/TEXT/YESNO field `CHECK TYPE` metadata mismatches, NUMBER/TEXT/YESNO-expectation unknown-field `CHECK TYPE` diagnostics, missing-object field assignment and `CHECK TYPE` diagnostics, NUMBER/TEXT/YESNO wrong-type diagnostics, NUMBER/TEXT/YESNO-valued unknown-field diagnostics for direct assignments to undeclared fields, plus a plain beginner-facing unknown-field diagnostic when the assigned expression type is not inferable yet
 
 Still needed:

docs/ROADMAP.md

@@ -31,7 +31,7 @@ See `CURRENT_STATUS.md` for the detailed feature matrix.
 
 1. Keep beginner-facing docs current and separate from historical release notes.
 2. Keep examples aligned with the modern simple syntax (`END`, `DO`, short `SET`, short `ASK`) while documenting older compatibility forms separately.
-3. Expand validation around typecheck diagnostics and package/networking safety. Current Forgejo/Gitea CI runs the documented release gates (`claro validate`, typecheck diagnostics validation, version convention validation, and CI workflow coverage validation). Current package safety validation covers safe manifest/lockfile creation, rejecting unsafe package names during `package add`, detecting unsafe package names already present in `claro.project` during `package doctor`, refusing to write lockfile data for unsafe package names during `package lock`, and making `package remove` fail instead of reporting success when unsafe package names remain during lockfile refresh. Current function validation covers correct checked calls, wrong-type arguments, missing checked-argument diagnostics, and extra-argument diagnostics; current object-method parameter validation covers correct modern `DO object.method ...` and compatibility `CALL object.method WITH ...` checked calls, wrong-type diagnostics for both call forms, a missing checked-argument diagnostic, missing-object guidance when `DO player.method ...` or compatibility `CALL object.method WITH ...` appears before `NEW` even if the method name is also wrong, and a class-specific unknown-method diagnostic when a learner calls a method the class does not declare; object-field validation covers correct NUMBER, TEXT, and YESNO direct `SET object.field value` assignments, direct `CHECK TYPE` metadata acceptance for NUMBER/TEXT/YESNO fields, negative NUMBER/TEXT/YESNO metadata mismatches, NUMBER/TEXT/YESNO-expectation unknown-field `CHECK TYPE` diagnostics, missing-object field assignment and `CHECK TYPE` diagnostics, NUMBER/TEXT/YESNO wrong-type direct assignments, simple NUMBER/TEXT/YESNO-valued unknown-field diagnostics after `NEW Class object`, and a beginner-facing fallback when the unknown field's assigned expression type is not inferable yet.
+3. Expand validation around typecheck diagnostics and package/networking safety. Current Forgejo/Gitea CI runs the documented release gates (`claro validate`, typecheck diagnostics validation, version convention validation, and CI workflow coverage validation). Current package safety validation covers safe manifest/lockfile creation, rejecting unsafe package names during `package add`, detecting unsafe package names already present in `claro.project` during `package doctor`, refusing to write lockfile data for unsafe package names during `package lock`, and making `package remove` fail instead of reporting success when unsafe package names remain during lockfile refresh. Current function validation covers correct checked calls, wrong-type arguments, missing checked-argument diagnostics, and extra-argument diagnostics; current object-method parameter validation covers correct modern `DO object.method ...` and compatibility `CALL object.method WITH ...` checked calls, wrong-type diagnostics for both call forms, missing and extra checked-argument diagnostics, missing-object guidance when `DO player.method ...` or compatibility `CALL object.method WITH ...` appears before `NEW` even if the method name is also wrong, and a class-specific unknown-method diagnostic when a learner calls a method the class does not declare; object-field validation covers correct NUMBER, TEXT, and YESNO direct `SET object.field value` assignments, direct `CHECK TYPE` metadata acceptance for NUMBER/TEXT/YESNO fields, negative NUMBER/TEXT/YESNO metadata mismatches, NUMBER/TEXT/YESNO-expectation unknown-field `CHECK TYPE` diagnostics, missing-object field assignment and `CHECK TYPE` diagnostics, NUMBER/TEXT/YESNO wrong-type direct assignments, simple NUMBER/TEXT/YESNO-valued unknown-field diagnostics after `NEW Class object`, and a beginner-facing fallback when the unknown field's assigned expression type is not inferable yet.
 4. Add small examples for each foundation feature before adding bigger syntax.
 
 ## Complete-platform milestones

src/claro.c

@@ -560,7 +560,7 @@ static int typecheck_file(const char *path){ FILE *f=fopen(path,"rb"); char line
   else if(!strcmp(up,"TYPE")&&starts_ci(t,"TYPE OF")){ char *name=check_var_after_as(t); if(name){ type_env_set(&types,name,"TEXT"); free(name); } }
   else if(!strcmp(up,"NEW")){ const char *as=find_word_ci(t,"AS"); char *name=NULL; char *cls=NULL; char objtype[256]; if(as){ cls=substr(t+3,as); name=xstrdup(trim_inplace((char*)as+2)); } else { const char *pcur=t+3; cls=unquote_token(&pcur); name=unquote_token(&pcur); } snprintf(objtype,sizeof(objtype),"OBJECT:%s",trim_inplace(cls)); if(name&&*trim_inplace(name)){ TypeFieldCheck *fc; char fullname[256]; char *nt=trim_inplace(name); char *ct=trim_inplace(cls); type_env_set(&types,nt,objtype); for(fc=field_checks;fc;fc=fc->next){ if(ci_eq(fc->cls,ct)){ snprintf(fullname,sizeof(fullname),"%s.%s",nt,fc->field); type_env_set(&types,fullname,fc->type); } } } free(cls); free(name); }
   else if((!strcmp(up,"DO")&&!find_word_ci(t,"TIMES"))||!strcmp(up,"CALL")){ char *fname=NULL; char **parts=NULL; int ac=0,i,is_method=0; char lookup[256],display[256]; if(!strcmp(up,"DO")){ const char *pcur=t+2; fname=unquote_token(&pcur); if(*trim_inplace((char*)pcur)) ac=split_args(pcur,&parts); } else { char *rest=t+4; const char *with=find_word_ci(rest,"WITH"); fname=with?substr(rest,with):xstrdup(rest); if(with) ac=split_args(with+4,&parts); } snprintf(lookup,sizeof(lookup),"%s",trim_inplace(fname)); snprintf(display,sizeof(display),"%s",lookup); { char *dot=strchr(lookup,'.'); if(dot){ char objname[128]; const char *objtype; snprintf(objname,sizeof(objname),"%.*s",(int)(dot-lookup),lookup); objtype=type_env_get(types,objname); if(objtype&&starts_ci(objtype,"OBJECT:")){ char method[128]; const char *cls=objtype+7; snprintf(method,sizeof(method),"%s",dot+1); if(!type_method_check_for(method_checks,cls,method)){ printf("%s:%d: Object %s has no method %s. Check the method name or add TEACH %s inside CLASS %s.\n",path,line_no,cls,method,method,cls); errs++; } snprintf(lookup,sizeof(lookup),"%s.%s",cls,method); snprintf(display,sizeof(display),"%s",lookup); is_method=1; }
-       else if(!objtype||(!starts_ci(objtype,"MODULE")&&(!strcmp(up,"DO")||type_method_name_exists(method_checks,dot+1)))){ printf("%s:%d: Object %s is not known yet. Create it with NEW ClassName %s before calling %s.\n",path,line_no,objname,objname,lookup); errs++; } } } for(i=0;i<ac;i++){ const char *param=NULL; const char *need=type_param_check_for(param_checks,lookup,i,&param); const char *got=simple_expr_type(types,parts[i]); if(need&&got&&!type_words_match(need,got)){ printf("%s:%d: Type mismatch for %s %s: parameter %s needs %s, but this argument looks like %s.\n",path,line_no,is_method?"method":"function",display,param?param:"argument",need,got); errs++; } } { TypeParamCheck *pc=param_checks; while(pc){ if(ci_eq(pc->func,lookup)&&pc->pos>=ac){ printf("%s:%d: %s %s needs argument %s as %s, but this call does not provide it.\n",path,line_no,is_method?"Method":"Function",display,pc->param,pc->type); errs++; } pc=pc->next; } } { int expected=type_arity_check_for(arity_checks,lookup); if(expected>=0&&ac>expected&&!is_method){ printf("%s:%d: %s %s only accepts %d %s, but this call gives %d. Remove the extra %s.\n",path,line_no,is_method?"Method":"Function",display,expected,expected==1?"argument":"arguments",ac,ac-expected==1?"argument":"arguments"); errs++; } } free(fname); }
+       else if(!objtype||(!starts_ci(objtype,"MODULE")&&(!strcmp(up,"DO")||type_method_name_exists(method_checks,dot+1)))){ printf("%s:%d: Object %s is not known yet. Create it with NEW ClassName %s before calling %s.\n",path,line_no,objname,objname,lookup); errs++; } } } for(i=0;i<ac;i++){ const char *param=NULL; const char *need=type_param_check_for(param_checks,lookup,i,&param); const char *got=simple_expr_type(types,parts[i]); if(need&&got&&!type_words_match(need,got)){ printf("%s:%d: Type mismatch for %s %s: parameter %s needs %s, but this argument looks like %s.\n",path,line_no,is_method?"method":"function",display,param?param:"argument",need,got); errs++; } } { TypeParamCheck *pc=param_checks; while(pc){ if(ci_eq(pc->func,lookup)&&pc->pos>=ac){ printf("%s:%d: %s %s needs argument %s as %s, but this call does not provide it.\n",path,line_no,is_method?"Method":"Function",display,pc->param,pc->type); errs++; } pc=pc->next; } } { int expected=type_arity_check_for(arity_checks,lookup); if(expected>=0&&ac>expected){ printf("%s:%d: %s %s only accepts %d %s, but this call gives %d. Remove the extra %s.\n",path,line_no,is_method?"Method":"Function",display,expected,expected==1?"argument":"arguments",ac,ac-expected==1?"argument":"arguments"); errs++; } } free(fname); }
   else if(!strcmp(up,"CHECK")&&starts_ci(t,"CHECK TYPE")){ const char *is=find_word_ci(t,"IS"); if(is){ char *expr=substr(t+10,is); char *need=xstrdup(trim_inplace((char*)is+2)); char *et=trim_inplace(expr); const char *got=simple_expr_type(types,et); if(got&&!type_words_match(need,got)){ printf("%s:%d: Type check failed: expected %s, but %s looks like %s.\n",path,line_no,need,et,got); errs++; } else if(!got&&strchr(et,'.')){ char objname[128],fieldname[128]; char *dot=strchr(et,'.'); const char *objtype; snprintf(objname,sizeof(objname),"%.*s",(int)(dot-et),et); snprintf(fieldname,sizeof(fieldname),"%s",dot+1); objtype=type_env_get(types,objname); if(objtype&&starts_ci(objtype,"OBJECT:")&&!type_field_check_for(field_checks,objtype+7,fieldname)){ printf("%s:%d: Object %s has no field %s. Check the field name or add HAS %s %s to the class.\n",path,line_no,objtype+7,fieldname,fieldname,need); errs++; } else if(!objtype){ printf("%s:%d: Object %s is not known yet. Create it with NEW ClassName %s before checking %s.\n",path,line_no,objname,objname,et); errs++; } } free(expr); free(need); } else { printf("%s:%d: CHECK TYPE needs IS. Try: CHECK TYPE score IS NUMBER\n",path,line_no); errs++; } }
  }
  fclose(f); if(errs==0) printf("Type check OK\n"); return errs?1:0; }

tests/typecheck_method_extra_arg_bad.claro

@@ -0,0 +1,11 @@
+CLASS Player
+    HAS score NUMBER
+
+    TEACH add points
+        CHECK TYPE points IS NUMBER
+        SET score score + points
+    END
+END
+
+NEW Player player
+DO player.add 5, 6

tools/validate_typecheck_diagnostics.py

@@ -38,6 +38,9 @@ EXPECTED = {
     "tests/typecheck_method_missing_arg_bad.claro": [
         "tests/typecheck_method_missing_arg_bad.claro:11: Method Player.add needs argument points as NUMBER, but this call does not provide it.",
     ],
+    "tests/typecheck_method_extra_arg_bad.claro": [
+        "tests/typecheck_method_extra_arg_bad.claro:11: Method Player.add only accepts 1 argument, but this call gives 2. Remove the extra argument.",
+    ],
     "tests/typecheck_method_unknown_object_bad.claro": [
         "tests/typecheck_method_unknown_object_bad.claro:10: Object player is not known yet. Create it with NEW ClassName player before calling player.add.",
     ],