Add check that no database has been loaded

Author: AlexanderWells-diamond

softioc/builder.py

@@ -274,9 +274,6 @@ def longStringOut(name, **fields):
 # ----------------------------------------------------------------------------
 #  Support routines for builder
 
-
-_DatabaseWritten = False
-
 def LoadDatabase():
     '''This should be called after all the builder records have been created,
     but before calling iocInit().  The database is loaded into EPICS memory,
@@ -293,6 +290,8 @@ def LoadDatabase():
 
 def ClearRecords():
     """Delete all created record information, allowing new record creation"""
+    assert not pythonSoftIoc.RecordWrapper.is_builder_reset(), \
+        'Record database has already been loaded'
     RecordLookup._RecordDirectory.clear()
     ResetRecords()
 

softioc/pythonSoftIoc.py

@@ -17,7 +17,7 @@ class RecordWrapper(object):
     __builder_reset = False
 
     def __init__(self, builder, device, name, **fields):
-        assert not self.__builder_reset, \
+        assert not self.is_builder_reset(), \
             'It\'s too late to create records'
         # List of keyword arguments expected by the device constructor.  The
         # remaining arguments are passed to the builder.  It's a shame we
@@ -47,6 +47,12 @@ def reset_builder(cls):
         for instance in cls.__Instances:
             instance.__set('__builder', None)
 
+    @classmethod
+    def is_builder_reset(cls):
+        '''Returns True if it is too late to create records'''
+        return cls.__builder_reset
+
+
 
     # Most attributes delegate directly to the builder instance until the
     # database has been written.  At this point the builder instance has been

tests/test_records.py

@@ -255,6 +255,39 @@ def test_clear_records():
     for key, val in LookupRecordList():
         assert key == full_name
 
+def clear_records_runner(child_conn):
+    """Tests ClearRecords after loading the database"""
+    builder.aOut("Some-Record")
+    builder.LoadDatabase()
+
+    try:
+        builder.ClearRecords()
+    except AssertionError:
+        # Expected error
+        child_conn.send("D")  # "Done"
+    child_conn.send("F")  # "Fail"
+
+def test_clear_records_too_late():
+    """Test that calling ClearRecords after a database has been loaded raises
+    an exception"""
+    ctx = get_multiprocessing_context()
+
+    parent_conn, child_conn = ctx.Pipe()
+
+    process = ctx.Process(
+        target=clear_records_runner,
+        args=(child_conn,),
+    )
+
+    process.start()
+
+    try:
+        select_and_recv(parent_conn, "D")
+    finally:
+        process.join(timeout=TIMEOUT)
+        if process.exitcode is None:
+            pytest.fail("Process did not terminate")
+
 
 
 def validate_fixture_names(params):