Add compliance test for sparse query parameters

modules/protocol-tests/resources/META-INF/smithy/Pizza.smithy

@@ -9,7 +9,7 @@ use alloy#simpleRestJson
 service PizzaAdminService {
     version: "1.0.0",
     errors: [GenericServerError, GenericClientError],
-    operations: [AddMenuItem, GetMenu, Version, Health, HeaderEndpoint, RoundTrip, GetEnum, GetIntEnum, CustomCode, HttpPayloadWithDefault]
+    operations: [AddMenuItem, GetMenu, Version, Health, HeaderEndpoint, RoundTrip, GetEnum, GetIntEnum, CustomCode, HttpPayloadWithDefault, SparseQueryParam]
 }
 
 @http(method: "POST", uri: "/restaurant/{restaurant}/menu/item", code: 201)
@@ -316,3 +316,37 @@ structure HttpPayloadWithDefaultInputOutput {
     @default("default value")
     body: String,
 }
+
+
+@readonly
+@http(uri: "/sparseQueryParam", method: "GET")
+operation SparseQueryParam {
+    input: SparseQueryParamInput,
+    output: SparseQueryParamOutput
+}
+
+structure SparseQueryParamInput {
+    @httpQuery("foo")
+    @required
+    foo: FooList
+
+    @httpQuery("bar")
+    @required
+    bar: BarList
+}
+
+structure SparseQueryParamOutput {
+    @httpPayload
+    @required
+    foo: FooList
+}
+
+@sparse
+list FooList {
+    member: String
+}
+
+@sparse
+list BarList {
+    member: Integer
+}

modules/protocol-tests/resources/META-INF/smithy/SparseQueryParameter.smithy

@@ -0,0 +1,32 @@
+$version: "2.0"
+
+namespace alloy.test
+
+use alloy#simpleRestJson
+use smithy.test#httpRequestTests
+use smithy.test#httpResponseTests
+
+apply SparseQueryParam @httpRequestTests([
+    {
+        id: "SparseQueryParam"
+        documentation: "Tests sparse query param serialization"
+        protocol: simpleRestJson
+        method: "GET"
+        uri: "/sparseQueryParam"
+        params: {
+            foo: ["bar", null, "baz", ""],
+            bar: [1, null, 2, null]
+        }
+        queryParams: [
+            "foo=bar",
+            "foo",
+            "foo=baz",
+            "foo=",
+            "bar=1",
+            "bar",
+            "bar=2",
+            "bar="
+        ]
+
+    }
+])

modules/protocol-tests/resources/META-INF/smithy/manifest

@@ -9,4 +9,5 @@ Pizza.smithy
 RoundTrip.smithy
 Version.smithy
 HttpPayloadWithDefault.smithy
+SparseQueryParameter.smithy
 test-config.json