[Format] Don't sort includes if DisableFormat is true

[njames93]

Summary

Fixes https://llvm.org/PR35099.

I'm not sure if this decision was intentional but its definitely confusing for users.

[MyDeveloperDay]

I've seen this asked for multiple time, I think this is fine.

[HazardyKnusperkeks]

Jep, that would also confuse myself.

[curdeius]

Is it testable?

[njames93]

In D101628#2734501, @curdeius wrote:

Is it testable?

I guess it would be, gimme a few to have a look at format unittests and I'll rustle up a quick test.

[njames93]

Add test case demonstrating new behvaiour.

[curdeius]

LGTM. Thanks!

clang/lib/Format/Format.cpp

 }
 
 bool isLikelyXml(StringRef Code) { return Code.ltrim().startswith("<"); }
 
 tooling::Replacements sortIncludes(const FormatStyle &Style, StringRef Code,
                                    ArrayRef<tooling::Range> Ranges,
                                    StringRef FileName, unsigned *Cursor) {
   tooling::Replacements Replaces;
-  if (!Style.SortIncludes)
+  if (!Style.SortIncludes || Style.DisableFormat)
     return Replaces;
   if (isLikelyXml(Code))
     return Replaces;
   if (Style.Language == FormatStyle::LanguageKind::LK_JavaScript &&
       isMpegTS(Code))
     return Replaces;
   if (Style.Language == FormatStyle::LanguageKind::LK_JavaScript)
     return sortJavaScriptImports(Style, Code, Ranges, FileName);

clang/unittests/Format/SortIncludesTest.cpp

 //===- unittest/Format/SortIncludesTest.cpp - Include sort unit tests -----===//
 //
 // 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 "FormatTestUtils.h"
 #include "clang/Format/Format.h"
 #include "llvm/ADT/None.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Debug.h"
 #include "gtest/gtest.h"
 
 #define DEBUG_TYPE "format-test"
 
 namespace clang {
 namespace format {
 namespace {
TEST_F(SortIncludesTest, MergeLines) {
   std::string Expected = "#include \"a.h\"\r\n"
                          "#include \"b\\\r\n"
                          ".h\"\r\n"
                          "#include \"c.h\"\r\n";
 
   EXPECT_EQ(Expected, sort(Code, "a.cpp", 1));
 }
 
+TEST_F(SortIncludesTest, DisableFormatDisablesIncludeSorting) {
+  StringRef Sorted = "#include <a.h>\n"
+                     "#include <b.h>\n";
+  StringRef Unsorted = "#include <b.h>\n"
+                       "#include <a.h>\n";
+  EXPECT_EQ(Sorted, sort(Unsorted));
+  FmtStyle.DisableFormat = true;
+  EXPECT_EQ(Unsorted, sort(Unsorted, "input.cpp", 0));
+}
+
 } // end namespace
 } // end namespace format
 } // end namespace clang