Improve compatibility and tests

README.md

@@ -3,8 +3,9 @@ python-hosts
 [![codecov](https://codecov.io/gh/jonhadfield/python-hosts/branch/devel/graph/badge.svg)](https://codecov.io/gh/jonhadfield/python-hosts) [![Docs](https://img.shields.io/badge/docs-latest-brightgreen.svg?style=flat)](http://python-hosts.readthedocs.org/en/latest/)
 
 
-This is a python library for managing a hosts file. 
+This is a python library for managing a hosts file.
 It enables you to add and remove entries, or import them from a file or URL.
+It remains compatible with Python 2.7 as well as modern Python 3 releases.
 
 Documentation
 -------------
@@ -42,7 +43,7 @@ A command line client using python-hosts can be found here: https://github.com/j
 Requirements
 ------------
 
-Tested on python 2.7, 3.5, 3.6, 3.7, 3.8, 3.9, pypy and pypy3
+Tested on Python 2.7 and Python 3.5+, including PyPy variants
 
 
 License

python_hosts/hosts.py

@@ -118,24 +118,16 @@ def str_to_hostentry(entry):
         :return: An instance of HostsEntry
         """
         split_line = entry.split('#', 1)
-        inline_comment = None
-        if len(split_line) == 2:
-            inline_comment = split_line[1].strip()
-            line_parts = split_line[0].strip().split()
-        else:
-            line_parts = entry.strip().split()
-        if is_ipv4(line_parts[0]) and valid_hostnames(line_parts[1:]):
-            return HostsEntry(entry_type='ipv4',
-                              address=line_parts[0],
-                              names=line_parts[1:],
+        line = split_line[0].strip().split()
+        inline_comment = split_line[1].strip() if len(split_line) == 2 else None
+
+        if is_ipv4(line[0]) and valid_hostnames(line[1:]):
+            return HostsEntry('ipv4', address=line[0], names=line[1:],
                               comment=inline_comment)
-        elif is_ipv6(line_parts[0]) and valid_hostnames(line_parts[1:]):
-            return HostsEntry(entry_type='ipv6',
-                              address=line_parts[0],
-                              names=line_parts[1:],
+        if is_ipv6(line[0]) and valid_hostnames(line[1:]):
+            return HostsEntry('ipv6', address=line[0], names=line[1:],
                               comment=inline_comment)
-        else:
-            return False
+        return False
 
 
 class Hosts(object):
@@ -187,11 +179,16 @@ def determine_hosts_path(platform=None):
         """
         if not platform:
             platform = sys.platform
-        if platform.startswith('win'):
-            result = r"c:\windows\system32\drivers\etc\hosts"
-            return result
-        else:
-            return '/etc/hosts'
+
+        paths = {
+            'win': r"c:\windows\system32\drivers\etc\hosts",
+            'default': '/etc/hosts'
+        }
+
+        for key, value in paths.items():
+            if key != 'default' and platform.startswith(key):
+                return value
+        return paths['default']
 
     def write(self, path=None, mode='w'):
         """
@@ -267,12 +264,8 @@ def exists(self, address=None, names=None, comment=None):
             if self.find_all_matching(address=address, name=name, comment=comment):
                 return True
 
-        for entry in self.entries:
-            if entry.entry_type == 'comment' and entry.comment == comment:
-                return True
-            # elif entry.entry_type in ('ipv4', 'ipv6'):
-            #     pass # already covered above
-        return False
+        return any(entry.entry_type == 'comment' and entry.comment == comment
+                   for entry in self.entries)
 
     def remove_all_matching(self, address=None, name=None, comment=None):
         """
@@ -304,22 +297,14 @@ def find_all_matching(self, address=None, name=None, comment=None):
         :param comment: A host inline comment
         :return: HostEntry instances
         """
-        results = []
-        if address or name or comment:
-            for entry in self.entries:
-                if not entry.is_real_entry():
-                    continue
-                if address:
-                    if address != entry.address:
-                        continue
-                if name:
-                    if name not in entry.names:
-                        continue
-                if comment:
-                    if comment != entry.comment:
-                        continue
-                results.append(entry)
-        return results
+        if not any((address, name, comment)):
+            return []
+
+        return [entry for entry in self.entries
+                if entry.is_real_entry()
+                and (address is None or entry.address == address)
+                and (name is None or name in entry.names)
+                and (comment is None or entry.comment == comment)]
 
     def import_url(self, url=None, force=None):
         """

tests/test_utils.py

@@ -2,7 +2,7 @@
 import os
 import sys
 
-from python_hosts.utils import is_ipv4, is_ipv6, valid_hostnames
+from python_hosts.utils import is_ipv4, is_ipv6, valid_hostnames, dedupe_list, is_readable
 sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
 
 
@@ -52,3 +52,17 @@ def test_hostname_validation_failure_with_leading_hyphen():
     Test function returns False if a hostname with a leading hyphen is specified
     """
     assert not valid_hostnames(['example.com', '-example'])
+
+
+def test_dedupe_list_preserves_order():
+    """Ensure dedupe_list removes duplicates while keeping order."""
+    items = ['a', 'b', 'a', 'c', 'b']
+    assert dedupe_list(items) == ['a', 'b', 'c']
+
+
+def test_is_readable(tmpdir):
+    """Check is_readable returns expected values."""
+    readable = tmpdir.join('file')
+    readable.write('data')
+    assert is_readable(readable.strpath)
+    assert not is_readable(readable.strpath + '_missing')