[clang-tools-extra] [clang-doc] Add HTMLMustacheGenerator methods (PR #138061)

[Daniel Thornburgh via cfe-commits]

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@@ -40,13 +42,43 @@ getClangDocContext(std::vector<std::string> UserStylesheets = {},
   return CDCtx;
 }
 
+static void verifyFileContents(const Twine &Path, StringRef Contents) {
+  auto Buffer = MemoryBuffer::getFile(Path);
+  ASSERT_TRUE((bool)Buffer);
+  StringRef Data = Buffer.get()->getBuffer();
+  ASSERT_EQ(Data, Contents);
+}
+
 TEST(HTMLMustacheGeneratorTest, createResources) {
   auto G = getHTMLMustacheGenerator();
   ASSERT_THAT(G, NotNull()) << "Could not find HTMLMustacheGenerator";
   ClangDocContext CDCtx = getClangDocContext();
+  EXPECT_THAT_ERROR(G->createResources(CDCtx), Failed())
+      << "Empty UserStylesheets or JsScripts should fail!";
+
+  unittest::TempDir RootTestDirectory("createResourcesTest", /*Unique=*/true);
+  CDCtx.OutDirectory = RootTestDirectory.path();
+
+  unittest::TempFile CSS("clang-doc-mustache", "css", "CSS");
+  unittest::TempFile JS("mustache", "js", "JavaScript");
+
+  CDCtx.UserStylesheets[0] = CSS.path();
+  CDCtx.JsScripts[0] = JS.path();
 
   EXPECT_THAT_ERROR(G->createResources(CDCtx), Succeeded())
-      << "Failed to create resources.";
+      << "Failed to create resources with valid UserStylesheets and JsScripts";
+  {
+    SmallString<256> PathBuff;
----------------
mysterymath wrote:

nit: I don't know that I've ever come across `Buff`; `Buf` is typical abbreviation in my experience.

https://github.com/llvm/llvm-project/pull/138061