PR: Fix error edge line in python2.7

spyder/tests/tests_py3compat_usage.py

@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+
+import os
+import re
+
+root_path = os.path.realpath(os.path.join(os.getcwd(), 'spyder'))
+
+pattern = re.compile("isinstance\(.*,.*str\)")
+
+
+def test_dont_use_isinstance_str():
+    found = False
+    for dir_name, _, file_list in os.walk(root_path):
+        for fname in file_list:
+            if fname.endswith('.py') and fname != 'py3compat.py':
+                file = os.path.join(dir_name, fname)
+
+                for i, line in enumerate(open(file)):
+                    for match in re.finditer(pattern, line):
+                        print("{}\nline:{}, {}".format(file, i + 1, line))
+                        found = True
+
+    assert found == False, ("Don't use builtin isinstance() function,"
+                            "use spyder.py3compat.is_text_string() instead")

spyder/widgets/panels/edgeline.py

@@ -12,6 +12,7 @@
 from qtpy.QtCore import Qt, QRect
 from qtpy.QtGui import QPainter, QColor
 
+from spyder.py3compat import is_text_string
 
 class EdgeLine(QWidget):
     """Source code editor's edge line (default: 79 columns, PEP8)"""
@@ -53,7 +54,7 @@ def set_columns(self, columns):
         """Set edge line columns values."""
         if isinstance(columns, tuple):
             self.columns = columns
-        elif isinstance(columns, str):
+        elif is_text_string(columns):
             self.columns = tuple(int(e) for e in columns.split(','))
 
         self.update()

spyder/widgets/panels/manager.py

@@ -14,7 +14,7 @@
 from spyder.api.manager import Manager
 from spyder.api.panel import Panel
 from spyder.config.base import debug_print
-
+from spyder.py3compat import is_text_string
 
 class PanelsManager(Manager):
     """
@@ -94,7 +94,7 @@ def get(self, name_or_klass):
         :param name_or_klass: Name or class of the panel to retrieve.
         :return: The specified panel instance.
         """
-        if not isinstance(name_or_klass, str):
+        if not is_text_string(name_or_klass, str):
             name_or_klass = name_or_klass.__name__
         for zone in range(4):
             try:

spyder/workers/updates.py

@@ -14,7 +14,7 @@
 # Local imports
 from spyder import __version__
 from spyder.config.base import _
-from spyder.py3compat import PY3
+from spyder.py3compat import PY3, is_text_string
 from spyder.utils.programs import check_version, is_stable_version
 
 
@@ -76,7 +76,7 @@ def start(self):
                 data = page.read()
 
                 # Needed step for python3 compatibility
-                if not isinstance(data, str):
+                if not is_text_string(data, str):
                     data = data.decode()
 
                 data = json.loads(data)