[clang-format] Only add pragma continuation indentation for 'omp' clauses

The patch in D136100 added custom handling for pragmas to assist in
formatting OpenMP clauses correctly. One of these changes added extra
indentation. This is desirable for OpenMP pragmas as they are several
complete tokens that would otherwise we on the exact same line. However,
this is not desired for the other pragmas.

This solution is extremely hacky, I'm not overly familiar with the
`clang-format` codebase. A better solution would probably require
actually parsing these as tokens, but I just wanted to propose a
solution.

Fixes #59473

Reviewed By: HazardyKnusperkeks

Differential Revision: https://reviews.llvm.org/D144884

Author: jhuber6

clang/lib/Format/ContinuationIndenter.cpp

@@ -1273,8 +1273,13 @@ unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
     return ContinuationIndent;
   }
 
-  if (State.Line->InPragmaDirective)
-    return CurrentState.Indent + Style.ContinuationIndentWidth;
+  // OpenMP clauses want to get additional indentation when they are pushed onto
+  // the next line.
+  if (State.Line->InPragmaDirective) {
+    FormatToken *PragmaType = State.Line->First->Next->Next;
+    if (PragmaType && PragmaType->TokenText.equals("omp"))
+      return CurrentState.Indent + Style.ContinuationIndentWidth;
+  }
 
   // This ensure that we correctly format ObjC methods calls without inputs,
   // i.e. where the last element isn't selector like: [callee method];

clang/unittests/Format/FormatTest.cpp

@@ -20560,6 +20560,21 @@ TEST_F(FormatTest, UnderstandsPragmas) {
             "(including parentheses).",
             format("#pragma    mark   Any non-hyphenated or hyphenated string "
                    "(including parentheses)."));
+
+  EXPECT_EQ("#pragma mark Any non-hyphenated or hyphenated string "
+            "(including parentheses).",
+            format("#pragma    mark   Any non-hyphenated or hyphenated string "
+                   "(including parentheses)."));
+
+  EXPECT_EQ(
+      "#pragma comment(linker,    \\\n"
+      "                \"argument\" \\\n"
+      "                \"argument\"",
+      format("#pragma comment(linker,      \\\n"
+             "                 \"argument\" \\\n"
+             "                 \"argument\"",
+             getStyleWithColumns(
+                 getChromiumStyle(FormatStyle::LanguageKind::LK_Cpp), 32)));
 }
 
 TEST_F(FormatTest, UnderstandsPragmaOmpTarget) {