[clang-format] Inherit RightAlign options across scopes

[rymiel]

Summary

D119599 added the ability to align compound assignments, right aligning
them in order to line up at the equals sign.
However, that patch didn't account for AlignTokens being called
recursively across scopes, which reset the right justification to be
false in any scope besides the top scope. This meant the compound
assignments were aligned, just not at the right place.
(No tests also ever introduced any scopes)

This patch makes sure to inherit the right justification value, just as
every other parameter is passed on.

Fixes https://github.com/llvm/llvm-project/issues/58029

[owenpan]

LGTM

[MyDeveloperDay]

Nice!

clang/lib/Format/WhitespaceManager.cpp

for (unsigned e = Changes.size(); i != e; ++i) {
 
     if (!Changes[i].Tok->is(tok::comment))
       LineIsComment = false;
 
     if (Changes[i].Tok->is(tok::comma)) {
       ++CommasBeforeMatch;
     } else if (Changes[i].indentAndNestingLevel() > IndentAndNestingLevel) {
       // Call AlignTokens recursively, skipping over this scope block.
-      unsigned StoppedAt = AlignTokens(Style, Matches, Changes, i, ACS);
+      unsigned StoppedAt =
+          AlignTokens(Style, Matches, Changes, i, ACS, RightJustify);
       i = StoppedAt - 1;
       continue;
     }
 
     if (!Matches(Changes[i]))
       continue;
 
     // If there is more than one matching token per line, or if the number of

clang/unittests/Format/FormatTest.cpp

TEST_F(FormatTest, AlignCompoundAssignments) {
   verifyFormat("sfdbddfbdfbb   ^= 5;\n"
                "dvsdsv         |= 5;\n"
                "int dsvvdvsdvvv = 123;",
                Alignment);
   verifyFormat("sfdbddfbdfbb   ^= 5;\n"
                "dvsdsv        <<= 5;\n"
                "int dsvvdvsdvvv = 123;",
                Alignment);
+  verifyFormat("int xxx = 5;\n"
+               "xxx     = 5;\n"
+               "{\n"
+               "  int yyy = 6;\n"
+               "  yyy     = 6;\n"
+               "}",
+               Alignment);
+  verifyFormat("int xxx = 5;\n"
+               "xxx    += 5;\n"
+               "{\n"
+               "  int yyy = 6;\n"
+               "  yyy    += 6;\n"
+               "}",
+               Alignment);
   // Test that `<=` is not treated as a compound assignment.
   verifyFormat("aa &= 5;\n"
                "b <= 10;\n"
                "c = 15;",
                Alignment);
   Alignment.AlignConsecutiveAssignments.PadOperators = true;
   verifyFormat("sfdbddfbdfbb    = 5;\n"
                "dvsdsv          = 5;\n"