Add symlink support to pkg_zip (#499)

* add symlink support to pkg_zip.  #309
* update tests to new mklink attributes

.gitignore

@@ -1,3 +1,3 @@
+.bazeliskrc
 .ijwb
 bazel-*
-

pkg/private/zip/build_zip.py

@@ -27,6 +27,7 @@
 # Unix dir bit and Windows dir bit. Magic from zip spec
 UNIX_DIR_BIT = 0o40000
 MSDOS_DIR_BIT = 0x10
+UNIX_SYMLINK_BIT = 0o120000
 
 def _create_argument_parser():
   """Creates the command line arg parser."""
@@ -108,6 +109,11 @@ def _add_manifest_entry(options, zip_file, entry, default_mode, ts):
     # Set directory bits
     entry_info.external_attr |= (UNIX_DIR_BIT << 16) | MSDOS_DIR_BIT
     zip_file.writestr(entry_info, '')
+  elif entry_type == manifest.ENTRY_IS_LINK:
+    entry_info.compress_type = zipfile.ZIP_STORED
+    # Set directory bits
+    entry_info.external_attr |= (UNIX_SYMLINK_BIT << 16)
+    zip_file.writestr(entry_info, src)
   # TODO(#309): All the rest
 
 def main(args):

tests/zip/BUILD

@@ -13,7 +13,7 @@
 # limitations under the License.
 # -*- coding: utf-8 -*-
 
-load("//pkg:mappings.bzl", "pkg_attributes", "pkg_mkdirs")
+load("//pkg:mappings.bzl", "pkg_attributes", "pkg_mkdirs", "pkg_mklink")
 load("//pkg:zip.bzl", "pkg_zip")
 load("//tests/util:defs.bzl", "directory", "fake_artifact")
 load("@rules_python//python:defs.bzl", "py_test")
@@ -42,6 +42,15 @@ pkg_mkdirs(
     ],
 )
 
+pkg_mklink(
+    name = "link",
+    target = "/usr/local/foo/foo.real",
+    link_name = "/usr/bin/foo",
+    attributes = pkg_attributes(
+        mode = "555",
+    ),
+)
+
 directory(
     name = "generate_tree",
     contents = "hello there",
@@ -79,6 +88,7 @@ pkg_zip(
         "//tests:testdata/hello.txt",
         "//tests:testdata/loremipsum.txt",
         ":dirs",
+        ":link",
     ],
 )
 
@@ -107,6 +117,7 @@ pkg_zip(
         "//tests:testdata/hello.txt",
         "//tests:testdata/loremipsum.txt",
         ":dirs",
+        ":link",
     ],
     timestamp = 0,
 )

tests/zip/zip_test.py

@@ -26,6 +26,7 @@
 # Unix dir bit and Windows dir bit. Magic from zip spec
 UNIX_DIR_BIT = 0o40000
 MSDOS_DIR_BIT = 0x10
+UNIX_RWX_BITS = 0o777
 
 # The ZIP epoch date: (1980, 1, 1, 0, 0, 0)
 _ZIP_EPOCH_DT = datetime.datetime(1980, 1, 1, 0, 0, 0, tzinfo=datetime.timezone.utc)
@@ -76,7 +77,7 @@ def assertZipFileContent(self, zip_file, content):
           expect_dir_bits = UNIX_DIR_BIT << 16 | MSDOS_DIR_BIT
           self.assertEqual(info.external_attr & expect_dir_bits,
                            expect_dir_bits)
-        self.assertEqual(info.external_attr >> 16 & ~UNIX_DIR_BIT,
+        self.assertEqual((info.external_attr >> 16) & UNIX_RWX_BITS,
                          expected.get("attr", 0o555))
 
   def test_empty(self):
@@ -87,6 +88,7 @@ def test_basic(self):
         {"filename": "foodir/", "isdir": True, "attr": 0o711},
         {"filename": "hello.txt", "crc": HELLO_CRC},
         {"filename": "loremipsum.txt", "crc": LOREM_CRC},
+        {"filename": "usr/bin/foo", "attr": 0o555, "data": "/usr/local/foo/foo.real"},
     ])
 
   def test_timestamp(self):