[clang] [Format] Configure ASSIGN_OR_RETURN macros for Google style (PR #169037)

[Ilya Biryukov via cfe-commits]

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@@ -144,6 +145,12 @@ TEST(ConfigParseTest, GetsCorrectBasedOnStyle) {
   EXPECT_EQ(0, parseConfiguration(TEXT, &Style).value());                      \
   EXPECT_EQ(VALUE, Style.FIELD) << "Unexpected value after parsing!"
 
+#define CHECK_PARSE_THAT(TEXT, FIELD, MATCHER)                                 \
+  EXPECT_THAT(Style.FIELD, ::testing::Not(MATCHER))                            \
+      << "Initial value already matches!";                                     \
+  EXPECT_EQ(0, parseConfiguration(TEXT, &Style).value());                      \
+  EXPECT_THAT(Style.FIELD, (MATCHER)) << "Does not match after parsing!";
+
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ilya-biryukov wrote:

Done.

https://github.com/llvm/llvm-project/pull/169037