From e867bb59b73d8b26fb1d85d3bedc521e3326b076 Mon Sep 17 00:00:00 2001
From: Aaron Helsinger <ahelsing@bbn.com>
Date: Fri, 11 Oct 2019 12:08:09 -0400
Subject: [PATCH] Working on issue #32; add some unit tests and make QReference
 hashable. But sets still fail

---
 src/python/pyqgl2/qreg.py | 17 +++++++++++++++--
 test/test_qregister.py    | 19 +++++++++++++++++++
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/python/pyqgl2/qreg.py b/src/python/pyqgl2/qreg.py
index b9a7cfe..44a1075 100644
--- a/src/python/pyqgl2/qreg.py
+++ b/src/python/pyqgl2/qreg.py
@@ -106,7 +106,13 @@ def addArg(self, x, args):
                 # FIXME: Print warning?
                 pass
         elif isinstance(x, QReference):
-            self.addArg(x.ref[x.idx], args)
+            self.addArg(x.ref.qubits[x.idx], args)
+        elif isinstance(x, int):
+            if x not in self.qubits:
+                self.qubits.append(x)
+            else:
+                # duplicate - skip
+                pass
         else:
             raise NameError(f"Invalid QRegister constructor 'QRegister({args})'; arg {x} unknown.")
 
@@ -206,7 +212,14 @@ def __eq__(self, other):
         return (self.ref == other.ref) and (self.idx == other.idx)
 
     def __len__(self):
-        return len(self.ref.qubits[self.idx])
+        x = self.ref.qubits[self.idx]
+        if isinstance(x, int):
+            return 1
+        else:
+            return len(x)
+
+    def __hash__(self):
+        return hash(self.ref) + hash(self.idx)
 
     def use_name(self):
         return self.ref.use_name()
diff --git a/test/test_qregister.py b/test/test_qregister.py
index 7d3e72a..82668be 100644
--- a/test/test_qregister.py
+++ b/test/test_qregister.py
@@ -2,6 +2,7 @@
 
 import ast
 from pyqgl2.qreg import QRegister, QReference
+from test.helpers import channel_setup
 
 class TestQRegister(unittest.TestCase):
     def setUp(self):
@@ -37,6 +38,24 @@ def test_qref(self):
         self.assertEqual(b.ref, a)
         self.assertEqual(b.idx, 2)
 
+    # Supplying qubit of same name/index multiple times is no-op; remove duplicates
+    # Can use lists and tuples too; sets don't work yet
+    def test_unique(self):
+        a = QRegister(3)
+        b = QRegister('q3')
+        c = QRegister(QRegister(a))
+        d = QRegister(a,[b,a],(c,a))
+        self.assertEqual(a,d)
+
+    # QRegister from Qubit produces QRegister of same name
+    def test_qreg_from_qubit(self):
+        from QGL import QubitFactory
+        channel_setup()
+        a = QRegister(1)
+        bq = QubitFactory('q1')
+        c = QRegister((bq,))
+        self.assertEqual(a, c)
+
     def test_factory(self):
         node = ast.parse("a = QRegister('q1', 'q5')").body[0]
         a = QRegister.factory(node, {})