add unit tests for url encoding

MODULE.bazel

@@ -28,6 +28,11 @@ bazel_dep(
     version = "6.0.2",
     dev_dependency = True,
 )
+bazel_dep(
+    name = "rules_testing",
+    version = "0.6.0",
+    dev_dependency=True,
+)
 bazel_dep(
     name = "stardoc",
     version = "0.7.0",

tests/unit/url_encoding/BUILD.bazel

@@ -0,0 +1,3 @@
+load(":test_url_encoding.bzl", "url_encoding_test_suite")
+
+url_encoding_test_suite(name="test_url_encoding")

tests/unit/url_encoding/test_url_encoding.bzl

@@ -0,0 +1,29 @@
+load("@rules_testing//lib:analysis_test.bzl", "test_suite", "analysis_test")
+load("@rules_testing//lib:util.bzl", "util")
+load("//gcs/private:url_encoding.bzl", "url_encode", "url_decode")
+
+def _test_url_encode(env):
+    env.expect.that_str(url_encode("foo")).equals("foo")
+    env.expect.that_str(url_encode("a/b/c")).equals("a%2fb%2fc")
+    env.expect.that_str(url_encode("🖥️")).equals("%f0%9f%96%a5%ef%b8%8f")
+
+def _test_url_decode(env):
+    env.expect.that_str(url_decode("foo")).equals("foo")
+    env.expect.that_str(url_decode("a%2fb%2fc")).equals("a/b/c")
+    env.expect.that_str(url_decode("%f0%9f%96%a5%ef%b8%8f")).equals("🖥️")
+
+def _test_invariant_holds(env):
+    _invariant(env, """ !"#$%&\'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~""")
+
+def _invariant(env, s):
+    env.expect.that_str(url_decode(url_encode(s))).equals(s)
+
+def url_encoding_test_suite(name):
+    test_suite(
+        name = name,
+        basic_tests = [
+            _test_url_encode,
+            _test_url_decode,
+            _test_invariant_holds,
+        ]
+    )