PY-11274 Check right operand of format operator using abc.Mapping interface

python/src/com/jetbrains/python/inspections/PyStringFormatInspection.java

@@ -41,6 +41,7 @@ import java.util.Map;
 
 import static com.jetbrains.python.inspections.PyStringFormatParser.filterSubstitutions;
 import static com.jetbrains.python.inspections.PyStringFormatParser.parsePercentFormat;
+import static com.jetbrains.python.psi.PyUtil.as;
 
 /**
  * @author Alexey.Ivanov
@@ -416,9 +417,9 @@ public class PyStringFormatInspection extends PyInspection {
           inspectValues(((PyParenthesizedExpression)rightExpression).getContainedExpression());
         }
         else {
-          final PyType type = myTypeEvalContext.getType(rightExpression);
+          final PyClassType type = as(myTypeEvalContext.getType(rightExpression), PyClassType.class);
           if (type != null) {
-            if (myUsedMappingKeys.size() > 0 && !("dict".equals(type.getName()))) {
+            if (myUsedMappingKeys.size() > 0 && !PyABCUtil.isSubclass(type.getPyClass(), PyNames.MAPPING)) {
               registerProblem(rightExpression, PyBundle.message("INSP.format.requires.mapping"));
               return;
             }

python/testData/inspections/PyStringFormatInspection/src/string-format.py

@@ -102,4 +102,20 @@ print '%d, %d, %d, %d' % my_tuple[:7:3]
 print '%d %s' % ((42,) + ('spam',))
 print '%d %s' % (('ham',) + ('spam',))
 print '%d %s' % ((42,) + ())
-print '%d' % ((42,) + ('spam',))
+print '%d' % ((42,) + ('spam',))
+
+# PY-11274
+import collections
+print '%(foo)s' % collections.OrderedDict(foo=None)
+
+class MyDict(collections.Mapping):
+    def __getitem__(self, key):
+        return 'spam'
+
+    def __iter__(self):
+        yield 'spam'
+
+    def __len__(self):
+        return 1
+
+print '%(foo)s' % MyDict()