[Python-checkins] bpo-37960: Silence only necessary errors in repr() of buffered and text streams. (GH-15543)

[Miss Islington (bot)]

https://github.com/python/cpython/commit/102130a63c93fde7bcabbbf4fae1ebce38888981
commit: 102130a63c93fde7bcabbbf4fae1ebce38888981
branch: 3.8
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: GitHub <noreply at github.com>
date: 2019-08-29T01:13:29-07:00
summary:

bpo-37960: Silence only necessary errors in repr() of buffered and text streams. (GH-15543)

(cherry picked from commit b235a1b47394eedc5f8ea4cf214f56c4c6932e59)

Co-authored-by: Serhiy Storchaka <storchaka at gmail.com>

files:
A Misc/NEWS.d/next/Library/2019-08-27-10-52-13.bpo-37960.CTY7Lw.rst
M Lib/_pyio.py
M Modules/_io/bufferedio.c
M Modules/_io/textio.c

diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index 0b6493bc8dc9..650109295fe8 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -407,7 +407,7 @@ def __del__(self):
         """Destructor.  Calls close()."""
         try:
             closed = self.closed
-        except Exception:
+        except AttributeError:
             # If getting closed fails, then the object is probably
             # in an unusable state, so ignore.
             return
@@ -865,7 +865,7 @@ def __repr__(self):
         clsname = self.__class__.__qualname__
         try:
             name = self.name
-        except Exception:
+        except AttributeError:
             return "<{}.{}>".format(modname, clsname)
         else:
             return "<{}.{} name={!r}>".format(modname, clsname, name)
@@ -2079,13 +2079,13 @@ def __repr__(self):
                                  self.__class__.__qualname__)
         try:
             name = self.name
-        except Exception:
+        except AttributeError:
             pass
         else:
             result += " name={0!r}".format(name)
         try:
             mode = self.mode
-        except Exception:
+        except AttributeError:
             pass
         else:
             result += " mode={0!r}".format(mode)
diff --git a/Misc/NEWS.d/next/Library/2019-08-27-10-52-13.bpo-37960.CTY7Lw.rst b/Misc/NEWS.d/next/Library/2019-08-27-10-52-13.bpo-37960.CTY7Lw.rst
new file mode 100644
index 000000000000..421cfb9c38e1
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-08-27-10-52-13.bpo-37960.CTY7Lw.rst
@@ -0,0 +1,2 @@
+``repr()`` of buffered and text streams now silences only expected
+exceptions when get the value of "name" and "mode" attributes.
diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 44e12db6a30e..8e8ff97ff8c6 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -1378,12 +1378,14 @@ buffered_repr(buffered *self)
 {
     PyObject *nameobj, *res;
 
-    nameobj = _PyObject_GetAttrId((PyObject *) self, &PyId_name);
-    if (nameobj == NULL) {
-        if (PyErr_ExceptionMatches(PyExc_Exception))
-            PyErr_Clear();
-        else
+    if (_PyObject_LookupAttrId((PyObject *) self, &PyId_name, &nameobj) < 0) {
+        if (!PyErr_ExceptionMatches(PyExc_ValueError)) {
             return NULL;
+        }
+        /* Ignore ValueError raised if the underlying stream was detached */
+        PyErr_Clear();
+    }
+    if (nameobj == NULL) {
         res = PyUnicode_FromFormat("<%s>", Py_TYPE(self)->tp_name);
     }
     else {
diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
index 73b2756afce5..4fe1b295f885 100644
--- a/Modules/_io/textio.c
+++ b/Modules/_io/textio.c
@@ -2860,14 +2860,14 @@ textiowrapper_repr(textio *self)
         }
         goto error;
     }
-    nameobj = _PyObject_GetAttrId((PyObject *) self, &PyId_name);
-    if (nameobj == NULL) {
-        if (PyErr_ExceptionMatches(PyExc_Exception))
-            PyErr_Clear();
-        else
+    if (_PyObject_LookupAttrId((PyObject *) self, &PyId_name, &nameobj) < 0) {
+        if (!PyErr_ExceptionMatches(PyExc_ValueError)) {
             goto error;
+        }
+        /* Ignore ValueError raised if the underlying stream was detached */
+        PyErr_Clear();
     }
-    else {
+    if (nameobj != NULL) {
         s = PyUnicode_FromFormat(" name=%R", nameobj);
         Py_DECREF(nameobj);
         if (s == NULL)
@@ -2876,14 +2876,10 @@ textiowrapper_repr(textio *self)
         if (res == NULL)
             goto error;
     }
-    modeobj = _PyObject_GetAttrId((PyObject *) self, &PyId_mode);
-    if (modeobj == NULL) {
-        if (PyErr_ExceptionMatches(PyExc_Exception))
-            PyErr_Clear();
-        else
-            goto error;
+    if (_PyObject_LookupAttrId((PyObject *) self, &PyId_mode, &modeobj) < 0) {
+        goto error;
     }
-    else {
+    if (modeobj != NULL) {
         s = PyUnicode_FromFormat(" mode=%R", modeobj);
         Py_DECREF(modeobj);
         if (s == NULL)