Issue #20792: Expand idle_test.test_pathbowser. Tweak file to not copy twice.

Original patch by Saimadhav Heblikar.

Lib/idlelib/PathBrowser.py

@@ -17,6 +17,7 @@ class PathBrowser(ClassBrowser):
         self.init(flist)
 
     def settitle(self):
+        "Set window titles."
         self.top.wm_title("Path Browser")
         self.top.wm_iconname("Path Browser")
 
@@ -69,16 +70,17 @@ class DirBrowserTreeItem(TreeItem):
         return sublist
 
     def ispackagedir(self, file):
+        " Return true for directories that are packages."
         if not os.path.isdir(file):
-            return 0
+            return False
         init = os.path.join(file, "__init__.py")
         return os.path.exists(init)
 
     def listmodules(self, allnames):
         modules = {}
         suffixes = importlib.machinery.EXTENSION_SUFFIXES[:]
-        suffixes += importlib.machinery.SOURCE_SUFFIXES[:]
-        suffixes += importlib.machinery.BYTECODE_SUFFIXES[:]
+        suffixes += importlib.machinery.SOURCE_SUFFIXES
+        suffixes += importlib.machinery.BYTECODE_SUFFIXES
         sorted = []
         for suff in suffixes:
             i = -len(suff)
@@ -93,7 +95,7 @@ class DirBrowserTreeItem(TreeItem):
         sorted.sort()
         return sorted
 
-def _path_browser(parent):
+def _path_browser(parent):  # htest #
     flist = PyShellFileList(parent)
     PathBrowser(flist, _htest=True)
     parent.mainloop()

Lib/idlelib/idle_test/test_pathbrowser.py

 import unittest
-import idlelib.PathBrowser as PathBrowser
+import os
+import sys
+import idlelib
+from idlelib import PathBrowser
 
 class PathBrowserTest(unittest.TestCase):
 
@@ -7,6 +10,18 @@ class PathBrowserTest(unittest.TestCase):
         # Issue16226 - make sure that getting a sublist works
         d = PathBrowser.DirBrowserTreeItem('')
         d.GetSubList()
+        self.assertEqual('', d.GetText())
+
+        dir = os.path.split(os.path.abspath(idlelib.__file__))[0]
+        self.assertEqual(d.ispackagedir(dir), True)
+        self.assertEqual(d.ispackagedir(dir + '/Icons'), False)
+
+    def test_PathBrowserTreeItem(self):
+        p = PathBrowser.PathBrowserTreeItem()
+        self.assertEqual(p.GetText(), 'sys.path')
+        sub = p.GetSubList()
+        self.assertEqual(len(sub), len(sys.path))
+        self.assertEqual(type(sub[0]), PathBrowser.DirBrowserTreeItem)
 
 if __name__ == '__main__':
     unittest.main(verbosity=2, exit=False)