BUG: Fix subarray format changed in #8160

Preserving structured array element format,
this commit fixes subarray format changed in PR #8160.
This commit also changes iterator for field name from dtype_.descr to
dtype_.names (Related to #8174).

1 files changed, 31 insertions, 18 deletions

diff --git a/numpy/core/arrayprint.py b/numpy/core/arrayprint.py
index 7a84eb7c2..1d93a0c0b 100644
--- a/numpy/core/arrayprint.py
+++ b/numpy/core/arrayprint.py
@@ -234,24 +234,7 @@ def _boolFormatter(x):
 def repr_format(x):
     return repr(x)
 
-def _get_format_function(data, precision, suppress_small, formatter):
-    """
-    find the right formatting function for the dtype_
-    """
-    dtype_ = data.dtype
-    if dtype_.fields is not None:
-        format_functions = []
-        for descr in dtype_.descr:
-            field_name = descr[0]
-            field_values = data[field_name]
-            if len(field_values.shape) <= 1:
-                format_function = _get_format_function(
-                    field_values, precision, suppress_small, formatter)
-            else:
-                format_function = repr_format
-            format_functions.append(format_function)
-        return StructureFormat(format_functions)
-
+def _get_formatdict(data, precision, suppress_small, formatter):
     formatdict = {'bool': _boolFormatter,
                   'int': IntegerFormat(data),
                   'float': FloatFormat(data, precision, suppress_small),
@@ -285,7 +268,27 @@ def _get_format_function(data, precision, suppress_small, formatter):
             if key in fkeys:
                 formatdict[key] = formatter[key]
 
+    return formatdict
+
+def _get_format_function(data, precision, suppress_small, formatter):
+    """
+    find the right formatting function for the dtype_
+    """
+    dtype_ = data.dtype
+    if dtype_.fields is not None:
+        format_functions = []
+        for field_name in dtype_.names:
+            field_values = data[field_name]
+            is_array_field = 1 < field_values.ndim
+            format_function = _get_format_function(
+                    ravel(field_values), precision, suppress_small, formatter)
+            if is_array_field:
+                format_function = SubArrayFormat(format_function)
+            format_functions.append(format_function)
+        return StructureFormat(format_functions)
+
     dtypeobj = dtype_.type
+    formatdict = _get_formatdict(data, precision, suppress_small, formatter)
     if issubclass(dtypeobj, _nt.bool_):
         return formatdict['bool']
     elif issubclass(dtypeobj, _nt.integer):
@@ -781,6 +784,16 @@ class TimedeltaFormat(object):
             return self.format % x.astype('i8')
 
 
+class SubArrayFormat(object):
+    def __init__(self, format_function):
+        self.format_function = format_function
+
+    def __call__(self, arr):
+        if arr.ndim <= 1:
+            return "[" + ", ".join(self.format_function(a) for a in arr) + "]"
+        return "[" + ", ".join(self.__call__(a) for a in arr) + "]"
+
+
 class StructureFormat(object):
     def __init__(self, format_functions):
         self.format_functions = format_functions