Merge pull request #11340 from eric-wieser/fix-sctypeDict-clongdouble

BUG: sctypeDict['f8'] randomly points to double or longdouble depending on non-deterministic dictionary iteration order

2 files changed, 34 insertions, 22 deletions

diff --git a/numpy/core/numerictypes.py b/numpy/core/numerictypes.py
index 7cd80f432..727fb66d1 100644
--- a/numpy/core/numerictypes.py
+++ b/numpy/core/numerictypes.py
@@ -323,31 +323,37 @@ def _add_aliases():
 
         # insert bit-width version for this class (if relevant)
         base, bit, char = bitname(info.type)
-        if base != '':
-            myname = "%s%d" % (base, bit)
-            if (name not in ('longdouble', 'clongdouble') or
-                   myname not in allTypes):
-                base_capitalize = english_capitalize(base)
-                if base == 'complex':
-                    na_name = '%s%d' % (base_capitalize, bit//2)
-                elif base == 'bool':
-                    na_name = base_capitalize
-                else:
-                    na_name = "%s%d" % (base_capitalize, bit)
 
-                allTypes[myname] = info.type
+        assert base != ''
+        myname = "%s%d" % (base, bit)
+
+        # ensure that (c)longdouble does not overwrite the aliases assigned to
+        # (c)double
+        if name in ('longdouble', 'clongdouble') and myname in allTypes:
+            continue
+
+        base_capitalize = english_capitalize(base)
+        if base == 'complex':
+            na_name = '%s%d' % (base_capitalize, bit//2)
+        elif base == 'bool':
+            na_name = base_capitalize
+        else:
+            na_name = "%s%d" % (base_capitalize, bit)
+
+        allTypes[myname] = info.type
+
+        # add mapping for both the bit name and the numarray name
+        sctypeDict[myname] = info.type
+        sctypeDict[na_name] = info.type
 
-                # add mapping for both the bit name and the numarray name
-                sctypeDict[myname] = info.type
-                sctypeDict[na_name] = info.type
+        # add forward, reverse, and string mapping to numarray
+        sctypeNA[na_name] = info.type
+        sctypeNA[info.type] = na_name
+        sctypeNA[info.char] = na_name
 
-                # add forward, reverse, and string mapping to numarray
-                sctypeNA[na_name] = info.type
-                sctypeNA[info.type] = na_name
-                sctypeNA[info.char] = na_name
-        if char != '':
-            sctypeDict[char] = info.type
-            sctypeNA[char] = na_name
+        assert char != ''
+        sctypeDict[char] = info.type
+        sctypeNA[char] = na_name
 _add_aliases()
 
 def _add_integer_aliases():
diff --git a/numpy/core/tests/test_numerictypes.py b/numpy/core/tests/test_numerictypes.py
index cdf1b0490..4c3cc6c9e 100644
--- a/numpy/core/tests/test_numerictypes.py
+++ b/numpy/core/tests/test_numerictypes.py
@@ -406,3 +406,9 @@ class TestIsSubDType(object):
         for w1, w2 in itertools.product(self.wrappers, repeat=2):
             assert_(not np.issubdtype(w1(np.float32), w2(np.float64)))
             assert_(not np.issubdtype(w1(np.float64), w2(np.float32)))
+
+
+def TestSctypeDict(object):
+    def test_longdouble(self):
+        assert_(np.sctypeDict['f8'] is not np.longdouble)
+        assert_(np.sctypeDict['c16'] is not np.clongdouble)