bites 223

Author: [email protected]

.gitignore

@@ -53,3 +53,4 @@
 /159/README.md
 /142/README.md
 /127/README.md
+/223/README.md

223/permissions.py

@@ -0,0 +1,37 @@
+def get_octal_from_file_permission(rwx: str) -> str:
+    """Receive a Unix file permission and convert it to
+       its octal representation.
+
+       In Unix you have user, group and other permissions,
+       each can have read (r), write (w), and execute (x)
+       permissions expressed by r, w and x.
+
+       Each has a number:
+       r = 4
+       w = 2
+       x = 1
+
+       So this leads to the following input/ outputs examples:
+       rw-r--r-- => 644 (user = 4 + 2, group = 4, other = 4)
+       rwxrwxrwx => 777 (user/group/other all have 4 + 2 + 1)
+       r-xr-xr-- => 554 (user/group = 4 + 1, other = 4)
+    """
+
+    def count(ugo: str) -> str:
+        value = 0
+        for k, v in enumerate(ugo):
+            if v == "r":
+                value += 4
+            if v == "w":
+                value += 2
+            if v == "x":
+                value += 1
+        return str(value)
+    # :3
+    user = rwx[:3]
+    group = rwx[3:6]
+    # 6:
+    other = rwx[6:]
+    # :D
+    return count(user) + count(group) + count(other)
+

223/test_permissions.py

@@ -0,0 +1,28 @@
+import pytest
+
+from permissions import get_octal_from_file_permission
+
+
+@pytest.mark.parametrize("input_arg, expected", [
+    ('-----x-w-', '012'), ('-----x-wx', '013'), ('-----xr--', '014'),
+    ('-----xr-x', '015'), ('-----xrw-', '016'), ('-----xrwx', '017'),
+    ('----w--wx', '023'), ('----w-r--', '024'), ('----w-r-x', '025'),
+    ('----w-rw-', '026'), ('----w-rwx', '027'), ('----wxr--', '034'),
+    ('----wxr-x', '035'), ('----wxrw-', '036'), ('----wxrwx', '037'),
+    ('---r--r-x', '045'), ('---r--rw-', '046'), ('---r--rwx', '047'),
+    ('---r-xrw-', '056'), ('---r-xrwx', '057'), ('---rw-rwx', '067'),
+    ('--x-w--wx', '123'), ('--x-w-r--', '124'), ('--x-w-r-x', '125'),
+    ('--x-w-rw-', '126'), ('--x-w-rwx', '127'), ('--x-wxr--', '134'),
+    ('--x-wxr-x', '135'), ('--x-wxrw-', '136'), ('--x-wxrwx', '137'),
+    ('--xr--r-x', '145'), ('--xr--rw-', '146'), ('--xr--rwx', '147'),
+    ('--xr-xrw-', '156'), ('--xr-xrwx', '157'), ('--xrw-rwx', '167'),
+    ('-w--wxr--', '234'), ('-w--wxr-x', '235'), ('-w--wxrw-', '236'),
+    ('-w--wxrwx', '237'), ('-w-r--r-x', '245'), ('-w-r--rw-', '246'),
+    ('-w-r--rwx', '247'), ('-w-r-xrw-', '256'), ('-w-r-xrwx', '257'),
+    ('-w-rw-rwx', '267'), ('-wxr--r-x', '345'), ('-wxr--rw-', '346'),
+    ('-wxr--rwx', '347'), ('-wxr-xrw-', '356'), ('-wxr-xrwx', '357'),
+    ('-wxrw-rwx', '367'), ('r--r-xrw-', '456'), ('r--r-xrwx', '457'),
+    ('r--rw-rwx', '467'), ('r-xrw-rwx', '567'),
+])
+def test_octal_results_for_different_rwx_combinations(input_arg, expected):
+    assert get_octal_from_file_permission(input_arg) == expected