[clang] [ssaf][UnsafeBufferUsage] Add JSON serialization for UnsafeBufferUsage (PR #187156)

[Balázs Benics via cfe-commits]

================
@@ -184,6 +186,128 @@ TEST_F(UnsafeBufferUsageTest, UnsafeBufferUsageEntityPointerLevelSetTest) {
   EXPECT_THAT(getSubsetOf(Set, E3), UnorderedElementsAre(P5));
 }
 
+//////////////////////////////////////////////////////////////
+//                     JSON Tests                           //
+//////////////////////////////////////////////////////////////
+// Oracle JSON output for the example:
+// void foo(int ***p, int ****q, int x) {
+//   p[5][5][5];
+//   q[5][5][5][5];
+// }
+constexpr const char *const SerilizationTestOracle = R"cpp({
+  "UnsafeBuffers": [
+    [
+      {
+        "@": 42
+      },
+      1
+    ],
+    [
+      {
+        "@": 42
+      },
+      2
+    ],
+    [
+      {
+        "@": 42
+      },
+      3
+    ],
+    [
+      {
+        "@": 108
+      },
+      1
+    ],
+    [
+      {
+        "@": 108
+      },
+      2
+    ],
+    [
+      {
+        "@": 108
+      },
+      3
+    ],
+    [
+      {
+        "@": 108
+      },
+      4
+    ]
+  ]
+})cpp";
+
+TEST_F(UnsafeBufferUsageTest, UnsafeBufferUsageSerializeTest) {
+  auto Sum = setUpTest(R"cpp(
+    void foo(int ***p, int ****q, int x) {
+      p[5][5][5];
+      q[5][5][5][5];
+    }
+  )cpp",
+                       "foo");
+  ASSERT_NE(Sum, nullptr);
+  EXPECT_EQ(*Sum, makeSet(__LINE__, {{"p", 1U},
+                                     {"p", 2U},
+                                     {"p", 3U},
+                                     {"q", 1U},
+                                     {"q", 2U},
+                                     {"q", 3U},
+                                     {"q", 4U}}));
+
+  using Object = llvm::json::Object;
+
+  std::map<EntityId, uint64_t> DummyTable{{*getEntityId("p"), 42},
+                                          {*getEntityId("q"), 108}};
+  Object JData = UnsafeBufferUsageEntitySummary::jsonSerializeFn(
+      *Sum,
+      [&DummyTable](EntityId Id) { return Object{{"@", DummyTable[Id]}}; });
+
+  EXPECT_EQ(llvm::formatv("{0:2}", llvm::json::Value(std::move(JData))).str(),
+            SerilizationTestOracle);
+}
+
+TEST_F(UnsafeBufferUsageTest, UnsafeBufferUsageDeserializeTest) {
+  auto Sum = setUpTest(R"cpp(
+    void foo(int ***p, int ****q, int x) {
+      p[5][5][5];
+      q[5][5][5][5];
+    }
+  )cpp",
+                       "foo");
+  ASSERT_NE(Sum, nullptr);
+  EXPECT_EQ(*Sum, makeSet(__LINE__, {{"p", 1U},
+                                     {"p", 2U},
+                                     {"p", 3U},
+                                     {"q", 1U},
+                                     {"q", 2U},
+                                     {"q", 3U},
+                                     {"q", 4U}}));
+
+  using Object = llvm::json::Object;
+  using Value = llvm::json::Value;
----------------
steakhal wrote:

I almost recommended to move this to the top of the file, but I think that's not actually what I want now that I'm thinking about it.
Rather, just move all of these test files to a specific `UnsafeBufferUsageJSONTest.cpp` and there you have the right to have these usings at the top because it actually makes sense for a JSON-specific test file - while here in this file it would be awkward.

https://github.com/llvm/llvm-project/pull/187156