Fix Schemaview.get_uri(...) for no default_prefix in schema

linkml_runtime/utils/schemaview.py

@@ -15,7 +15,7 @@
 from linkml_runtime.utils.namespaces import Namespaces
 from deprecated.classic import deprecated
 from linkml_runtime.utils.context_utils import parse_import_map, map_import
-from linkml_runtime.utils.formatutils import is_empty, underscore, camelcase
+from linkml_runtime.utils.formatutils import camelcase, is_empty, sfx, underscore
 from linkml_runtime.utils.pattern import PatternResolver
 from linkml_runtime.linkml_model.meta import *
 from linkml_runtime.exceptions import OrderingError
@@ -1121,13 +1121,18 @@ def get_uri(self, element: Union[ElementName, Element], imports=True, expand=Fal
                     raise ValueError(f'Cannot find {e.from_schema} in schema_map')
             else:
                 schema = self.schema_map[self.in_schema(e.name)]
-            pfx = schema.default_prefix
             if use_element_type:
                 e_type = e.class_name.split("_",1)[0]  # for example "class_definition"
                 e_type_path = f"{e_type}/" 
             else:
                 e_type_path = ""
-            uri = f'{pfx}:{e_type_path}{e_name}'
+            pfx = schema.default_prefix
+            # To construct the uri we have to find out if the schema has a default_prefix 
+            # or if a pseudo "prefix" was derived from the schema id.
+            if pfx == sfx(str(schema.id)):  # no prefix defined in schema
+                uri = f'{pfx}{e_type_path}{e_name}'
+            else:
+                uri = f'{pfx}:{e_type_path}{e_name}'
         if expand:
             return self.expand_curie(uri)
         else:

tests/test_utils/test_schemaview.py

@@ -923,3 +923,17 @@ def test_type_and_slot_with_same_name():
     view.add_type(TypeDefinition(name="test", from_schema="https://example.org/imported#"))
 
     assert view.get_uri("test", imports=True) == "ex:test"
+
+
+def test_uris_without_default_prefix():
+    """
+    Test if uri is correct if no default_prefix is defined for the schema. Issue: linkml/linkml#2578
+    """
+    schema_definition = SchemaDefinition(id="https://example.org/test#", name="test_schema")
+
+    view = SchemaView(schema_definition)
+    view.add_class(ClassDefinition(name="TestClass", from_schema="https://example.org/another#"))
+    view.add_slot(SlotDefinition(name="test_slot", from_schema="https://example.org/another#"))
+
+    assert view.get_uri("TestClass", imports=True) == "https://example.org/test#TestClass"
+    assert view.get_uri("test_slot", imports=True) == "https://example.org/test#test_slot"