[clang-tools-extra] [clang-doc] integrate JSON generator with Mustache templates (PR #149006)

[Paul Kirth via cfe-commits]

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@@ -34,7 +34,7 @@ class Foo;
 // CHECK-NEXT:              <div>
 // CHECK-NEXT:                  <pre>
 // CHECK-NEXT:                      <code class="language-cpp code-clang-doc">
-// CHECK-NEXT:                          enum Color
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ilovepi wrote:

Is there a reason we'd want to drop this? Writing out that its an enum seems good, and IIRC was nicer in the generated HTML.

https://github.com/llvm/llvm-project/pull/149006