Add support and tests for List[str]

Note that these tests don't currently pass!

Author: AlexanderWells-diamond

softioc/builder.py

@@ -221,7 +221,7 @@ def _waveform(value, fields):
                 initial_value = numpy.require(initial_value, numpy.int32)
             elif initial_value.dtype == numpy.uint64:
                 initial_value = numpy.require(initial_value, numpy.uint32)
-            elif initial_value.dtype.char == "S":
+            elif initial_value.dtype.char in ("S", "U"):
                 initial_value = numpy.require(initial_value, numpy.dtype("S40"))
     else:
         initial_value = numpy.array([], dtype = datatype)

tests/test_record_values.py

@@ -207,6 +207,24 @@ def record_values_names(fixture_value):
         ),
         numpy.ndarray,
     ),
+    (
+        "wIn_string_array",
+        builder.WaveformIn,
+        ["123", "456", "7890"],
+        numpy.array(
+            [b"123", b"456", b"7890"], dtype=numpy.dtype("|S40")
+        ),
+        numpy.ndarray,
+    ),
+    (
+        "wOut_string_array",
+        builder.WaveformOut,
+        ["123", "456", "7890"],
+        numpy.array(
+            [b"123", b"456", b"7890"], dtype=numpy.dtype("|S40")
+        ),
+        numpy.ndarray,
+    ),
     (
         "longStringIn_str",
         builder.longStringIn,