Improve how we determine if a symbol was imported from other libraries

Author: ccordoba12

pylsp/plugins/symbols.py

@@ -33,27 +33,47 @@ def pylsp_document_symbols(config, document):
             if ' import ' in code or 'import ' in code:
                 continue
 
-            # Skip comparing module names.
+            # Skip imported symbols comparing module names.
             sym_full_name = d.full_name
-            module_name = document.dot_path
+            document_dot_path = document.dot_path
             if sym_full_name is not None:
-                # module_name returns where the symbol is imported, whereas
-                # full_name says where it really comes from. So if the parent
-                # modules in full_name are not in module_name, it means the
-                # symbol was not defined there.
-                # Note: The last element of sym_full_name is the symbol itself,
-                # so we don't need to use it below.
+                # We assume a symbol is imported from another module to start
+                # with.
                 imported_symbol = True
-                for mod in sym_full_name.split('.')[:-1]:
-                    if mod in module_name:
-                        imported_symbol = False
+
+                # The last element of sym_full_name is the symbol itself, so
+                # we need to discard it to do module comparisons below.
+                if '.' in sym_full_name:
+                    sym_module_name = sym_full_name.rpartition('.')[0]
+
+                # This is necessary to display symbols in init files (the checks
+                # below fail without it).
+                if document_dot_path.endswith('__init__'):
+                    document_dot_path = document_dot_path.rpartition('.')[0]
+
+                # document_dot_path is the module where the symbol is imported,
+                # whereas sym_module_name is the one where it was declared.
+                if sym_module_name.startswith(document_dot_path):
+                    # If sym_module_name starts with the same string as document_dot_path,
+                    # we can safely assume it was declared in the document.
+                    imported_symbol = False
+                elif sym_module_name.split('.')[0] in document_dot_path.split('.'):
+                    # If the first module in sym_module_name is one of the modules in
+                    # document_dot_path, we need to check if sym_module_name starts
+                    # with the modules in document_dot_path.
+                    document_mods = document_dot_path.split('.')
+                    for i in range(1, len(document_mods) + 1):
+                        submod = '.'.join(document_mods[-i:])
+                        if sym_module_name.startswith(submod):
+                            imported_symbol = False
+                            break
 
                 # When there's no __init__.py next to a file or in one of its
-                # parents, the check above fails. However, Jedi has a nice way
+                # parents, the checks above fail. However, Jedi has a nice way
                 # to tell if the symbol was declared in the same file: if
                 # full_name starts by __main__.
                 if imported_symbol:
-                    if not sym_full_name.startswith('__main__'):
+                    if not sym_module_name.startswith('__main__'):
                         continue
 
         try: