cppgenerator: rework keyword handling regarding unknown keywords

PySide has a distinction between functions with simple arguments and
functions with keyword arguments for optional keywords.

When a function has keywords specified in one or more signature
branch, it gets the METH_KEYWORDS flag. In this case, it is checked
that no argument is given positional and per keyword at the same time.

Completely forgotten was to check which keywords are allowed in that
branch, if at all. The problem was much complicated because
constructors can contain extra signals and properties.

At the same time, all further error messages are generated with Python.
This adds necessary flexibility when features are active.

All PyBuildValue objects were refcount leaking. That has been replaced
by static createStaticString expressions.
The `argNames` structure is no longer needed by the improved algorithm.

Change-Id: Ic297912c47231720f61c7d4b79b46a1e376a9941
Fixes: PYSIDE-1305
Task-number: PYSIDE-1019
Pick-to: 5.15
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

2 files changed, 20 insertions, 5 deletions

diff --git a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/errorhandler.py b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/errorhandler.py
index 7083fd1e6..76d2f2e9b 100644
--- a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/errorhandler.py
+++ b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/errorhandler.py
@@ -93,16 +93,31 @@ def matched_type(args, sigs):
     return None
 
 
-def seterror_argument(args, func_name):
+def seterror_argument(args, func_name, info):
     func = None
     try:
         func = eval(func_name, namespace)
     except Exception as e:
         msg = f"Internal error evaluating {func_name}: " + str(e)
         return TypeError, msg
+    if info and type(info) is str:
+        err = TypeError
+        if info == "<":
+            msg = f"{func_name}(): not enough arguments"
+        elif info == ">":
+            msg = f"{func_name}(): too many arguments"
+        elif info.isalnum():
+            msg = f"{func_name}(): got multiple values for keyword argument '{info}'"
+        else:
+            msg = f"{func_name}(): {info}"
+            err = AttributeError
+        return err, msg
+    if info and type(info) is dict:
+        msg = f"{func_name}(): unsupported keyword '{tuple(info)[0]}'"
+        return TypeError, msg
     sigs = get_signature(func, "typeerror")
     if not sigs:
-        msg = f"{func_name}({args} is wrong (missing signature)"
+        msg = f"{func_name}({args}) is wrong (missing signature)"
         return TypeError, msg
     if type(sigs) != list:
         sigs = [sigs]
@@ -143,7 +158,7 @@ def make_helptext(func):
         sigs = [sigs]
     try:
         func_name = func.__name__
-    except AttribureError:
+    except AttributeError:
         func_name = func.__func__.__name__
     sigtext = "\n".join(func_name + str(sig) for sig in sigs)
     msg = f"{sigtext}\n\n{existing_doc}" if check_string_type(existing_doc) else sigtext
diff --git a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/loader.py b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/loader.py
index 7b262783b..5a056aafd 100644
--- a/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/loader.py
+++ b/sources/shiboken6/shibokenmodule/files.dir/shibokensupport/signature/loader.py
@@ -99,8 +99,8 @@ def create_signature(props, key):
     return layout.create_signature(props, key)
 
 # name used in signature.cpp
-def seterror_argument(args, func_name):
-    return errorhandler.seterror_argument(args, func_name)
+def seterror_argument(args, func_name, info):
+    return errorhandler.seterror_argument(args, func_name, info)
 
 # name used in signature.cpp
 def make_helptext(func):