[clang-tools-extra] [clang-tidy] Improve redundant-casting check for binary operation (PR #191386)

[Gaurav Dhingra via cfe-commits]

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@@ -27,11 +27,24 @@ Options
 
 .. option:: IgnoreMacros
 
-   If set to `true`, the check will not give warnings inside macros. Default
-   is `true`.
+  If set to `true`, the check will not give warnings inside macros. Default
+  is `true`.
 
 .. option:: IgnoreTypeAliases
 
-   When set to `false`, the check will consider type aliases, and when set to
-   `true`, it will resolve all type aliases and operate on the underlying
-   types. Default is `false`.
+  When set to `false`, the check will consider type aliases, and when set to
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gxyd wrote:

> Currently we already mix 2 whitespaces and 3 whitespaces indention in the documentation.

That's true. Until now I had mostly seen 2 whitespaces, but `redundant-qualified-alias.rst` etc. (there are more) use 3 whitespaces as well.

https://github.com/llvm/llvm-project/pull/191386