8 files changed, 95 insertions, 5 deletions
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-4670634698080256.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-4670634698080256.testcase
new file mode 100644
index 0000000..4828f8a
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-4670634698080256.testcase
@@ -0,0 +1 @@
+ ےے      ے <css
+\ No newline at end of file
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5000587759190016.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5000587759190016.testcase
new file mode 100644
index 0000000..8a585ce
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5000587759190016.testcase
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5270998950477824.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5270998950477824.testcase
new file mode 100644
index 0000000..fd41142
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5270998950477824.testcase
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5375146639360000.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5375146639360000.testcase
new file mode 100644
index 0000000..6248b2c
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5375146639360000.testcase
@@ -0,0 +1 @@
+ے                 ><applet></applet><applet></applet><apple|><applet><applet><appl›„><applet><applet></applet></applet></applet></applet><applet></applet><apple>t<applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet>et><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><azplet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><plet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet><applet></applet></applet></applet></applet></appt></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet></applet><<meta charset=utf-8>
+\ No newline at end of file
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5492400320282624.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5492400320282624.testcase
new file mode 100644
index 0000000..107da53
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-5492400320282624.testcase
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6306874195312640.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6306874195312640.testcase
new file mode 100644
index 0000000..b60a250
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6306874195312640.testcase
@@ -0,0 +1 @@
+-      ےے  <math><select><mi><select><select>t
+\ No newline at end of file
diff --git a/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6401239223762944.testcase b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6401239223762944.testcase
new file mode 100644
index 0000000..d8bbca3
--- /dev/null
+++ b/bs4/tests/fuzz/clusterfuzz-testcase-minimized-bs4_fuzzer-6401239223762944.testcase
diff --git a/bs4/tests/test_fuzz.py b/bs4/tests/test_fuzz.py
index f778539..92728c0 100644
--- a/bs4/tests/test_fuzz.py
+++ b/bs4/tests/test_fuzz.py
@@ -14,13 +14,54 @@ from bs4 import (
     BeautifulSoup,
     ParserRejectedMarkup,
 )
+try:
+    from soupsieve.util import SelectorSyntaxError
+    import lxml
+    import html5lib
+    fully_fuzzable = True
+except ImportError:
+    fully_fuzzable = False
+    
 
+@pytest.mark.skipif(not fully_fuzzable, reason="Prerequisites for fuzz tests are not installed.")
 class TestFuzz(object):
 
     # Test case markup files from fuzzers are given this extension so
     # they can be included in builds.
     TESTCASE_SUFFIX = ".testcase"
 
+    # Copied 20230512 from
+    # https://github.com/google/oss-fuzz/blob/4ac6a645a197a695fe76532251feb5067076b3f3/projects/bs4/bs4_fuzzer.py
+    #
+    # Copying the code lets us precisely duplicate the behavior of
+    # oss-fuzz.  The downside is that this code changes over time, so
+    # multiple copies of the code must be kept around to run against
+    # older tests. I'm not sure what to do about this, but I may
+    # retire old tests after a time.
+    def fuzz_test_with_css(self, filename):
+        data = self.__markup(filename)
+        parsers = ['lxml-xml', 'html5lib', 'html.parser', 'lxml']
+        try:
+            idx = int(data[0]) % len(parsers)
+        except ValueError:
+            return
+
+        css_selector, data = data[1:10], data[10:]
+
+        try:
+            soup = BeautifulSoup(data[1:], features=parsers[idx])
+        except ParserRejectedMarkup:
+            return
+        except ValueError:
+            return
+
+        list(soup.find_all(True))
+        try:
+            soup.css.select(css_selector.decode('utf-8', 'replace'))
+        except SelectorSyntaxError:
+            return
+        soup.prettify()
+    
     # This class of error has been fixed by catching a less helpful
     # exception from html.parser and raising ParserRejectedMarkup
     # instead.
@@ -33,11 +74,14 @@ class TestFuzz(object):
         markup = self.__markup(filename)
         with pytest.raises(ParserRejectedMarkup):
             BeautifulSoup(markup, 'html.parser')
-
+            
     # This class of error has to do with very deeply nested documents
     # which overflow the Python call stack when the tree is converted
     # to a string. This is an issue with Beautiful Soup which was fixed
     # as part of [bug=1471755].
+    #
+    # These test cases are in the older format that doesn't specify
+    # which parser to use or give a CSS selector.
     @pytest.mark.parametrize(
         "filename", [
             "clusterfuzz-testcase-minimized-bs4_fuzzer-5984173902397440",
@@ -46,18 +90,44 @@ class TestFuzz(object):
             "clusterfuzz-testcase-minimized-bs4_fuzzer-6450958476902400",
         ]
     )
-    def test_deeply_nested_document(self, filename):
+    def test_deeply_nested_document_without_css(self, filename):
         # Parsing the document and encoding it back to a string is
         # sufficient to demonstrate that the overflow problem has
         # been fixed.
         markup = self.__markup(filename)
         BeautifulSoup(markup, 'html.parser').encode()
 
+    # This class of error has to do with very deeply nested documents
+    # which overflow the Python call stack when the tree is converted
+    # to a string. This is an issue with Beautiful Soup which was fixed
+    # as part of [bug=1471755].
+    @pytest.mark.parametrize(
+        "filename", [
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-5000587759190016",
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-5375146639360000",
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-5492400320282624",
+        ]
+    )
+    def test_deeply_nested_document(self, filename): 
+       self.fuzz_test_with_css(filename)
+        
+    @pytest.mark.parametrize(
+        "filename", [
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-4670634698080256",
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-5270998950477824",
+        ]
+    )
+    def test_soupsieve_errors(self, filename):
+        self.fuzz_test_with_css(filename)
+        
     # This class of error represents problems with html5lib's parser,
     # not Beautiful Soup. I use
     # https://github.com/html5lib/html5lib-python/issues/568 to notify
     # the html5lib developers of these issues.
-    @pytest.mark.skip("html5lib problems")
+    #
+    # These test cases are in the older format that doesn't specify
+    # which parser to use or give a CSS selector.
+    @pytest.mark.skip(reason="html5lib-specific problems")
     @pytest.mark.parametrize(
         "filename", [
             # b"""أ؟<!DOCTyPEV PUBLIC'''أگ'"""
@@ -68,7 +138,7 @@ class TestFuzz(object):
 
             # b'-<math><sElect><mi><sElect><sElect>'
             "clusterfuzz-testcase-minimized-bs4_fuzzer-5843991618256896",
-
+           
             # b'أ±<table><svg><html>'
             "clusterfuzz-testcase-minimized-bs4_fuzzer-6241471367348224",
 
@@ -79,10 +149,27 @@ class TestFuzz(object):
             "crash-0d306a50c8ed8bcd0785b67000fcd5dea1d33f08"
         ]
     )
-    def test_html5lib_parse_errors(self, filename):
+    def test_html5lib_parse_errors_without_css(self, filename):
         markup = self.__markup(filename)
         print(BeautifulSoup(markup, 'html5lib').encode())
 
+    # This class of error represents problems with html5lib's parser,
+    # not Beautiful Soup. I use
+    # https://github.com/html5lib/html5lib-python/issues/568 to notify
+    # the html5lib developers of these issues.
+    @pytest.mark.skip(reason="html5lib-specific problems")
+    @pytest.mark.parametrize(
+        "filename", [
+            # b'-      \xff\xff  <math>\x10<select><mi><select><select>t'
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-6306874195312640",
+
+            # b'\xb1<a>\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff'
+            "clusterfuzz-testcase-minimized-bs4_fuzzer-6401239223762944"
+        ]
+    )
+    def test_html5lib_parse_errors(self, filename):
+        self.fuzz_test_with_css(filename)
+        
     def __markup(self, filename):
         if not filename.endswith(self.TESTCASE_SUFFIX):
             filename += self.TESTCASE_SUFFIX