[clang] [clang-format] Add an option to format integer and float literal case (PR #151590)

[via cfe-commits]

================
@@ -0,0 +1,354 @@
+//===- unittest/Format/NumericLiteralCaseTest.cpp -------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "FormatTestBase.h"
+
+#define DEBUG_TYPE "numeric-literal-case-test"
+
+namespace clang {
+namespace format {
+namespace test {
+namespace {
+
+class NumericLiteralCaseTest : public FormatTestBase {};
+
+TEST_F(NumericLiteralCaseTest, Prefix) {
+  FormatStyle Style = getLLVMStyle();
+  EXPECT_EQ(Style.Language, FormatStyle::LK_Cpp);
+  EXPECT_EQ(Style.NumericLiteralCase.Prefix, FormatStyle::NLCS_Leave);
+  EXPECT_EQ(Style.NumericLiteralCase.HexDigit, FormatStyle::NLCS_Leave);
+  EXPECT_EQ(Style.NumericLiteralCase.ExponentLetter, FormatStyle::NLCS_Leave);
+  EXPECT_EQ(Style.NumericLiteralCase.Suffix, FormatStyle::NLCS_Leave);
+
+  constexpr StringRef Bin0{"b = 0b0'10'010uL;"};
+  constexpr StringRef Bin1{"b = 0B010'010Ul;"};
+  constexpr StringRef Hex0{"b = 0xdead'BEEFuL;"};
+  constexpr StringRef Hex1{"b = 0Xdead'BEEFUl;"};
+  verifyFormat(Bin0, Style);
+  verifyFormat(Bin1, Style);
+  verifyFormat(Hex0, Style);
+  verifyFormat(Hex1, Style);
----------------
owenca wrote:

```suggestion
  verifyFormat(Bin0);
  verifyFormat(Bin1);
  verifyFormat(Hex0);
  verifyFormat(Hex1);
```
Also, you can move lines 28-36 to the top.

https://github.com/llvm/llvm-project/pull/151590