From 3c07d8d52cef639dad501e86522db804796e0d6e Mon Sep 17 00:00:00 2001
From: whitequark <whitequark@whitequark.org>
Date: Tue, 1 Jan 2019 03:39:12 +0000
Subject: [PATCH] hdl.rec: include record name in error message.

---
 nmigen/hdl/rec.py           |  8 ++++++--
 nmigen/test/test_hdl_rec.py | 11 ++++++++++-
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/nmigen/hdl/rec.py b/nmigen/hdl/rec.py
index f291087..ef2fcb6 100644
--- a/nmigen/hdl/rec.py
+++ b/nmigen/hdl/rec.py
@@ -93,8 +93,12 @@ class Record(Value):
         try:
             return self.fields[name]
         except KeyError:
-            raise NameError("Record does not have a field '{}'. Did you mean one of: {}?"
-                            .format(name, ", ".join(self.fields))) from None
+            if self.name is None:
+                reference = "Unnamed record"
+            else:
+                reference = "Record '{}'".format(self.name)
+            raise NameError("{} does not have a field '{}'. Did you mean one of: {}?"
+                            .format(reference, name, ", ".join(self.fields))) from None
 
     def shape(self):
         return sum(len(f) for f in self.fields.values()), False
diff --git a/nmigen/test/test_hdl_rec.py b/nmigen/test/test_hdl_rec.py
index dd5cb7b..3f68247 100644
--- a/nmigen/test/test_hdl_rec.py
+++ b/nmigen/test/test_hdl_rec.py
@@ -85,5 +85,14 @@ class RecordTestCase(FHDLTestCase):
             ("ack", 1),
         ])
         with self.assertRaises(NameError,
-                msg="Record does not have a field 'en'. Did you mean one of: stb, ack?"):
+                msg="Record 'r' does not have a field 'en'. Did you mean one of: stb, ack?"):
+            r.en
+
+    def test_wrong_field_unnamed(self):
+        r = [Record([
+            ("stb", 1),
+            ("ack", 1),
+        ])][0]
+        with self.assertRaises(NameError,
+                msg="Unnamed record does not have a field 'en'. Did you mean one of: stb, ack?"):
             r.en
-- 
2.30.2