Correct terminology around NoSiteLinkError

Sitelinks are unique per wiki, not necessarily by language.

Change-Id: I315a62a51e1b035ac6be97e6267e998f3ffc6f98
---
M pywikibot/exceptions.py
M pywikibot/page/_wikibase.py
2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/pywikibot/exceptions.py b/pywikibot/exceptions.py
index cfe4601..e5c1a6a 100644
--- a/pywikibot/exceptions.py
+++ b/pywikibot/exceptions.py
@@ -107,7 +107,7 @@
 
 PageLoadRelatedError: any exception which happens while loading a Page.
   - InconsistentTitleError: Page receives a title inconsistent with query
-  - NoSiteLinkError: ItemPage has no sitelink to given language
+  - NoSiteLinkError: ItemPage has no sitelink to given site
 
 PageSaveRelatedError: page exceptions within the save operation on a Page
 
@@ -400,21 +400,21 @@
 
 class NoSiteLinkError(PageLoadRelatedError, NoPageError):
 
-    """ItemPage has no sitelink to the given language.
+    """ItemPage has no sitelink to the given site.
 
     .. versionadded:: 8.1
     .. deprecated:: 8.1
        :exc:`NoPageError` dependency.
     """
 
-    def __init__(self, page: 'pywikibot.page.ItemPage', lang: str) -> None:
+    def __init__(self, page: 'pywikibot.page.ItemPage', dbname: str) -> None:
         """Initializer.
 
         :param page: ItemPage that caused the exception
-        :param lang: language code of the queried sitelink
+        :param dbname: site identifier of the queried sitelink
 
         """
-        self.message = f'Item {{}} has no sitelink to language {lang!r}'
+        self.message = f'Item {{}} has no sitelink to {dbname!r}'
         super().__init__(page)
 
 
diff --git a/pywikibot/page/_wikibase.py b/pywikibot/page/_wikibase.py
index d7e9f5c..2083a3c 100644
--- a/pywikibot/page/_wikibase.py
+++ b/pywikibot/page/_wikibase.py
@@ -1078,7 +1078,8 @@
     def getSitelink(self, site, force: bool = False) -> str:
         """Return the title for the specific site.
 
-        If the item doesn't have that language, raise NoSiteLinkError.
+        If the item doesn't have a link to that site, raise
+        NoSiteLinkError.
 
         .. versionchanged:: 8.1
            raises NoSiteLinkError instead of NoPageError.
@@ -1095,7 +1096,9 @@
             self.get(force=force)
 
         if site not in self.sitelinks:
-            raise NoSiteLinkError(self, site.lang)
+            if not isinstance(site, str):
+                site = site.dbName()
+            raise NoSiteLinkError(self, site)
 
         return self.sitelinks[site].canonical_title()
 

