Clean up color in diff cli. Fix symlink detection

src/nancy/cli/diff.py

@@ -8,11 +8,11 @@ import warnings
 
 
 def print_diff(ABdiff: fs.FSDiff, version_info='count', indent=2,
-               indent_level=0, use_color=True):
+               indent_level=0, use_color=True, show_hashes=False):
     """Pretty print an FSDiff object"""
     if use_color:
         try:
-            from colorama import Fore, Back, Style
+            from colorama import init, Fore, Back, Style
         except ImportError:
             warnings.warn("Could not import colorama library. Color output disabled.")
             use_color = False
@@ -22,21 +22,52 @@ def print_diff(ABdiff: fs.FSDiff, version_info='count', indent=2,
         DEL=Fore.RED + 'DEL' + Style.RESET_ALL if use_color else 'DEL',
         MOD=Fore.YELLOW + 'MOD' + Style.RESET_ALL if use_color else 'MOD',
     )
+    filetypecolors = dict(
+        DIR=Fore.BLUE if use_color else '',
+        REG='',
+        LNK=Fore.CYAN if use_color else '',
+    )
+    reset = Style.RESET_ALL if use_color else ''
+    hashcolor = Fore.MAGENTA if use_color else ''
+
+    def _print_row(tag, entry, level):
+        relpath = entry.relpath[2:]
+
+        # Format relpath using filetype-based colors
+        dname, fname = os.path.split(relpath)
+        if fname == '':  # root directory leads to empty fname here
+            dirstr = (filetypecolors['DIR'] + '<root>' + reset)
+        else:
+            dirstr = (filetypecolors['DIR'] + dname + '/' + reset) \
+                if dname != '' else ''
+        fname = filetypecolors.get(entry.filetype, '') + fname + reset
+
+        if entry.filetype == 'LNK':  # append symlink target
+            fname += ' -> ' + entry.symlink_target
+
+        relpath = dirstr + fname
+
+        hashchange = (hashcolor + entry.sha256.hex() + reset +
+                     ' ' + changetags[tag]) \
+            if show_hashes else changetags[tag]
+
+        print(
+            hashchange,
+            entry.unfrozen_perms,
+            relpath,
+        )
 
     for l, d in ABdiff.flatten_tree():
         if d.A is None:
             assert d.B is not None
-            print(changetags['NEW'], d.B.unfrozen_perms,
-                #(indent_level + l) * indent * ' ' + d.B.filename,
-                    d.B.relpath[2:],
-            )
+            _print_row('NEW', d.B, l)
         elif d.B is None:
-            print(changetags['DEL'], d.A.unfrozen_perms, (indent_level + l) * indent * ' ' + d.A.filename)
+            _print_row('DEL', d.A, l)
         else:
-            print(changetags['MOD'], d.B.unfrozen_perms, (indent_level + l) * indent * ' ' + d.B.filename)
+            _print_row('MOD', d.B, l)
 
 
-def diff(store, filedir_path, version_info='count'):
+def diff(store, filedir_path, version_info='count', show_hashes=False, use_color=True):
     """Unwrapped diff command that prints a diff"""
     if not os.path.exists(filedir_path):
         raise FileNotFoundError(f"Cannot diff non-existent file or directory {filedir_path}")
@@ -44,7 +75,7 @@ def diff(store, filedir_path, version_info='count'):
     # get the diff object
     fsdiff = store.diff(filedir_path)
 
-    print_diff(fsdiff, version_info=version_info)
+    print_diff(fsdiff, version_info=version_info, show_hashes=show_hashes, use_color=use_color)
 
 
 @click.command()
@@ -55,7 +86,17 @@ def diff(store, filedir_path, version_info='count'):
     default='count',
     help='How much info to display about file versions.',
 )
-def diff_cli(path, version_info):
+@click.option(
+    '-H', "--show-hashes",
+    is_flag=True,
+    help='If given, prepend each line in the diff with the new file hash (SHA256).',
+)
+@click.option(
+    "--no-color",
+    is_flag=True,
+    help='If given, do not print any color output.',
+)
+def diff_cli(path, version_info, show_hashes, no_color):
     """Detect and describe changes to PATH
 
     PATH is a path to a file or directory inside an existing nancy store
@@ -77,7 +118,7 @@ def diff_cli(path, version_info):
     s = store.Store(storepath)
 
     try:
-        diff(store=s, filedir_path=path)
+        diff(store=s, filedir_path=path, show_hashes=show_hashes, use_color=not no_color)
     except FileNotFoundError as e:
         print(str(e), file=sys.stderr)
         sys.exit(1)

src/nancy/fs.py

@@ -113,7 +113,7 @@ class FSEntry:
 
         children = []
         symlink_target = None
-        if stat.S_ISLNK(s):
+        if os.path.islink(path):
             # Check links first, since it is not exclusive with dir or file checks
             filetype = 'LNK'
             symlink_target = os.readlink(path)