Add all_whl_requirements similar to rules_python (#93)

This is needed to generated the gazelle_manifest.yaml

e2e/bzlmod/BUILD.bazel

@@ -9,4 +9,5 @@ exports_files([
     "test_regex.py",
     "test_zstandard.py",
     "testlib.bzl",
+    "test_all_whl_requirements.py",
 ])

e2e/bzlmod/pdm/BUILD.bazel

@@ -1,5 +1,5 @@
 load("@bazel_skylib//rules:write_file.bzl", "write_file")
-load("@pdm//:requirements.bzl", "all_requirements", "requirement")
+load("@pdm//:requirements.bzl", "all_requirements", "all_whl_requirements", "requirement")
 load("@rules_pycross//pycross:defs.bzl", "pycross_wheel_build")
 load("@rules_python//python:defs.bzl", "py_test")
 
@@ -91,3 +91,13 @@ py_test(
     main = "test_regex.py",
     deps = all_requirements,
 )
+
+# Test using `all_whl_requirements`
+py_test(
+    name = "test_all_whl_requirements",
+    srcs = ["//:test_all_whl_requirements.py"],
+    env = {
+        "ALL_WHL_REQUIREMENTS": ",".join(all_whl_requirements),
+    },
+    main = "test_all_whl_requirements.py",
+)

e2e/bzlmod/test_all_whl_requirements.py

@@ -0,0 +1,12 @@
+import os
+import unittest
+
+
+class TestAllWhlRequirements(unittest.TestCase):
+    def test_all_whl_requirements(self):
+        self.maxDiff = None
+        self.assertNotEqual(os.environ["ALL_WHL_REQUIREMENTS"], "")
+
+
+if __name__ == "__main__":
+    unittest.main()

pycross/private/package_repo.bzl

@@ -147,6 +147,14 @@ def _requirements_bzl(rctx, pins):
     for pin in pins:
         lines.append('    "@@{repo_name}//:{pin}",'.format(repo_name = rctx.name, pin = pin))
     lines.append("]")
+    lines.extend([
+        "",
+        "# All wheel requirements",
+        "all_whl_requirements = [",
+    ])
+    for pin in pins.values():
+        lines.append('    "@@{repo_name}//_wheel:{pin}",'.format(repo_name = rctx.name, pin = pin))
+    lines.append("]")
 
     return "\n".join(lines) + "\n"