Fixes for handling .gitignore edge cases in GitIgnorePattern.

pathspec/gitignore.py

@@ -39,6 +39,12 @@ def __init__(self, pattern):
 			regex = None
 			include = None
 
+		elif pattern == '/':
+			# EDGE CASE: According to git check-ignore (v2.4.1)), a single '/'
+			# does not match any file.
+			regex = None
+			include = None
+
 		elif pattern:
 
 			if pattern.startswith('!'):
@@ -68,15 +74,24 @@ def __init__(self, pattern):
 				# paths. So, remove empty first segment to make pattern relative
 				# to root.
 				del pattern_segs[0]
-			else:
-				# A pattern without a beginning slash ('/') will match any
-				# descendant path. This is equivilent to "**/{pattern}". So,
-				# prepend with double-asterisks to make pattern relative to
-				# root.
+			elif len(pattern_segs) == 1 or \
+				 (len(pattern_segs) == 2 and not pattern_segs[1]):
+				# A **single** pattern without a beginning slash ('/') will
+				# match any descendant path. This is equivalent to
+				# "**/{pattern}". So, prepend with double-asterisks to make
+				# pattern relative to root.
+				# EDGE CASE: This also holds for a single pattern with a
+				# trailing slash (e.g. dir/).
 				if pattern_segs[0] != '**':
 					pattern_segs.insert(0, '**')
+			else:
+				# EDGE CASE: A pattern without a beginning slash ('/') but
+				# contains at least one prepended directory (e.g.
+				# "dir/{pattern}") should not match "**/dir/{pattern}",
+				# according to `git check-ignore` (v2.4.1).
+				pass
 
-			if not pattern_segs[-1]:
+			if not pattern_segs[-1] and len(pattern_segs) > 1:
 				# A pattern ending with a slash ('/') will match all descendant
 				# paths if it is a directory but not if it is a regular file.
 				# This is equivilent to "{pattern}/**". So, set last segment to
@@ -118,6 +133,13 @@ def __init__(self, pattern):
 					if need_slash:
 						regex.append('/')
 					regex.append(self._translate_segment_glob(seg))
+					if i == end and include == True:
+						# A pattern ending without a slash ('/') will match a file
+						# or a directory (with paths underneath it).
+						# e.g. foo matches: foo, foo/bar, foo/bar/baz, etc.
+						# EDGE CASE: However, this does not hold for exclusion cases
+						# according to `git check-ignore` (v2.4.1).
+						regex.append('(?:/.*)?')
 					need_slash = True
 			regex.append('$')
 			regex = ''.join(regex)

pathspec/tests/test_gitignore.py

@@ -22,21 +22,60 @@ def test_00_empty(self):
 		self.assertIsNone(spec.include)
 		self.assertIsNone(spec.regex)
 
+	def test_01_absolute_root(self):
+		"""
+		Tests a single root absolute path pattern.
+
+		This should NOT match any file (according to git check-ignore (v2.4.1)).
+		"""
+		spec = GitIgnorePattern('/')
+		self.assertIsNone(spec.include)
+		self.assertIsNone(spec.regex)
+
 	def test_01_absolute(self):
 		"""
 		Tests an absolute path pattern.
+
+		This should match:
+		an/absolute/file/path
+		an/absolute/file/path/foo
+
+		This should NOT match:
+		foo/an/absolute/file/path
 		"""
 		spec = GitIgnorePattern('/an/absolute/file/path')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^an/absolute/file/path$')
+		self.assertEquals(spec.regex.pattern, '^an/absolute/file/path(?:/.*)?$')
 
 	def test_01_relative(self):
 		"""
 		Tests a relative path pattern.
+
+		This should match:
+		spam
+		spam/
+		foo/spam
+		spam/foo
+		foo/spam/bar
 		"""
 		spec = GitIgnorePattern('spam')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?spam$')
+		self.assertEquals(spec.regex.pattern, '^(?:.+/)?spam(?:/.*)?$')
+
+	def test_01_relative_nested(self):
+		"""
+		Tests a relative nested path pattern.
+
+		This should match:
+		foo/spam
+		foo/spam/bar
+
+		This should **not** match (according to git check-ignore (v2.4.1)):
+		bar/foo/spam
+		"""
+		spec = GitIgnorePattern('foo/spam')
+		self.assertTrue(spec.include)
+		self.assertEquals(spec.regex.pattern, '^foo/spam(?:/.*)?$')
 
 	def test_02_comment(self):
 		"""
@@ -49,6 +88,9 @@ def test_02_comment(self):
 	def test_02_ignore(self):
 		"""
 		Tests an exclude pattern.
+
+		This should NOT match (according to git check-ignore (v2.4.1)):
+		temp/foo
 		"""
 		spec = GitIgnorePattern('!temp')
 		self.assertIsNotNone(spec.include)
@@ -59,18 +101,32 @@ def test_03_child_double_asterisk(self):
 		"""
 		Tests a directory name with a double-asterisk child
 		directory.
+
+		This should match:
+		spam/bar
+
+		This should **not** match (according to git check-ignore (v2.4.1)):
+		foo/spam/bar
 		"""
 		spec = GitIgnorePattern('spam/**')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?spam/.*$')
+		self.assertEquals(spec.regex.pattern, '^spam/.*$')
 
 	def test_03_inner_double_asterisk(self):
 		"""
 		Tests a path with an inner double-asterisk directory.
+
+		This should match:
+		left/bar/right
+		left/foo/bar/right
+		left/bar/right/foo
+
+		This should **not** match (according to git check-ignore (v2.4.1)):
+		foo/left/bar/right
 		"""
 		spec = GitIgnorePattern('left/**/right')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?left(?:/.+)?/right$')
+		self.assertEquals(spec.regex.pattern, '^left(?:/.+)?/right(?:/.*)?$')
 
 	def test_03_only_double_asterisk(self):
 		"""
@@ -83,38 +139,70 @@ def test_03_only_double_asterisk(self):
 	def test_03_parent_double_asterisk(self):
 		"""
 		Tests a file name with a double-asterisk parent directory.
+
+		This should match:
+		foo/spam
+		foo/spam/bar
 		"""
 		spec = GitIgnorePattern('**/spam')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?spam$')
+		self.assertEquals(spec.regex.pattern, '^(?:.+/)?spam(?:/.*)?$')
 
 	def test_04_infix_wildcard(self):
 		"""
 		Tests a pattern with an infix wildcard.
+
+		This should match:
+		foo--bar
+		foo-hello-bar
+		a/foo-hello-bar
+		foo-hello-bar/b
+		a/foo-hello-bar/b
 		"""
 		spec = GitIgnorePattern('foo-*-bar')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?foo\\-[^/]*\\-bar$')
+		self.assertEquals(spec.regex.pattern, '^(?:.+/)?foo\\-[^/]*\\-bar(?:/.*)?$')
 
 	def test_04_postfix_wildcard(self):
 		"""
 		Tests a pattern with a postfix wildcard.
+
+		This should match:
+		~temp-
+		~temp-foo
+		~temp-foo/bar
+		foo/~temp-bar
+		foo/~temp-bar/baz
 		"""
 		spec = GitIgnorePattern('~temp-*')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?\\~temp\\-[^/]*$')
+		self.assertEquals(spec.regex.pattern, '^(?:.+/)?\\~temp\\-[^/]*(?:/.*)?$')
 
 	def test_04_prefix_wildcard(self):
 		"""
 		Tests a pattern with a prefix wildcard.
+
+		This should match:
+		bar.py
+		bar.py/
+		foo/bar.py
+		foo/bar.py/baz
 		"""
 		spec = GitIgnorePattern('*.py')
 		self.assertTrue(spec.include)
-		self.assertEquals(spec.regex.pattern, '^(?:.+/)?[^/]*\\.py$')
+		self.assertEquals(spec.regex.pattern, '^(?:.+/)?[^/]*\\.py(?:/.*)?$')
 
 	def test_05_directory(self):
 		"""
 		Tests a directory pattern.
+
+		This should match:
+		dir/
+		foo/dir/
+		foo/dir/bar
+
+		This should **not** match:
+		dir
 		"""
 		spec = GitIgnorePattern('dir/')
 		self.assertTrue(spec.include)