Reland "Move #include manipulation code to new lib/Tooling/Inclusions."

This reverts commit r333534 (i.e. reland r332720) after fixing module build.

Differential Revision: https://reviews.llvm.org/D47068

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@333874 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 133 insertions, 0 deletions

diff --git a/include/clang/Tooling/Inclusions/IncludeStyle.h b/include/clang/Tooling/Inclusions/IncludeStyle.h
new file mode 100644
index 0000000000..42d6e1a5cf
--- /dev/null
+++ b/include/clang/Tooling/Inclusions/IncludeStyle.h
@@ -0,0 +1,133 @@
+//===--- IncludeStyle.h - Style of C++ #include directives -------*- C++-*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLING_INCLUSIONS_INCLUDESTYLE_H
+#define LLVM_CLANG_TOOLING_INCLUSIONS_INCLUDESTYLE_H
+
+#include "llvm/Support/YAMLTraits.h"
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace tooling {
+
+/// Style for sorting and grouping C++ #include directives.
+struct IncludeStyle {
+  /// Styles for sorting multiple ``#include`` blocks.
+  enum IncludeBlocksStyle {
+    /// Sort each ``#include`` block separately.
+    /// \code
+    ///    #include "b.h"               into      #include "b.h"
+    ///
+    ///    #include <lib/main.h>                  #include "a.h"
+    ///    #include "a.h"                         #include <lib/main.h>
+    /// \endcode
+    IBS_Preserve,
+    /// Merge multiple ``#include`` blocks together and sort as one.
+    /// \code
+    ///    #include "b.h"               into      #include "a.h"
+    ///                                           #include "b.h"
+    ///    #include <lib/main.h>                  #include <lib/main.h>
+    ///    #include "a.h"
+    /// \endcode
+    IBS_Merge,
+    /// Merge multiple ``#include`` blocks together and sort as one.
+    /// Then split into groups based on category priority. See
+    /// ``IncludeCategories``.
+    /// \code
+    ///    #include "b.h"               into      #include "a.h"
+    ///                                           #include "b.h"
+    ///    #include <lib/main.h>
+    ///    #include "a.h"                         #include <lib/main.h>
+    /// \endcode
+    IBS_Regroup,
+  };
+
+  /// Dependent on the value, multiple ``#include`` blocks can be sorted
+  /// as one and divided based on category.
+  IncludeBlocksStyle IncludeBlocks;
+
+  /// See documentation of ``IncludeCategories``.
+  struct IncludeCategory {
+    /// The regular expression that this category matches.
+    std::string Regex;
+    /// The priority to assign to this category.
+    int Priority;
+    bool operator==(const IncludeCategory &Other) const {
+      return Regex == Other.Regex && Priority == Other.Priority;
+    }
+  };
+
+  /// Regular expressions denoting the different ``#include`` categories
+  /// used for ordering ``#includes``.
+  ///
+  /// These regular expressions are matched against the filename of an include
+  /// (including the <> or "") in order. The value belonging to the first
+  /// matching regular expression is assigned and ``#includes`` are sorted first
+  /// according to increasing category number and then alphabetically within
+  /// each category.
+  ///
+  /// If none of the regular expressions match, INT_MAX is assigned as
+  /// category. The main header for a source file automatically gets category 0.
+  /// so that it is generally kept at the beginning of the ``#includes``
+  /// (http://llvm.org/docs/CodingStandards.html#include-style). However, you
+  /// can also assign negative priorities if you have certain headers that
+  /// always need to be first.
+  ///
+  /// To configure this in the .clang-format file, use:
+  /// \code{.yaml}
+  ///   IncludeCategories:
+  ///     - Regex:           '^"(llvm|llvm-c|clang|clang-c)/'
+  ///       Priority:        2
+  ///     - Regex:           '^(<|"(gtest|gmock|isl|json)/)'
+  ///       Priority:        3
+  ///     - Regex:           '.*'
+  ///       Priority:        1
+  /// \endcode
+  std::vector<IncludeCategory> IncludeCategories;
+
+  /// Specify a regular expression of suffixes that are allowed in the
+  /// file-to-main-include mapping.
+  ///
+  /// When guessing whether a #include is the "main" include (to assign
+  /// category 0, see above), use this regex of allowed suffixes to the header
+  /// stem. A partial match is done, so that:
+  /// - "" means "arbitrary suffix"
+  /// - "$" means "no suffix"
+  ///
+  /// For example, if configured to "(_test)?$", then a header a.h would be seen
+  /// as the "main" include in both a.cc and a_test.cc.
+  std::string IncludeIsMainRegex;
+};
+
+} // namespace tooling
+} // namespace clang
+
+LLVM_YAML_IS_SEQUENCE_VECTOR(clang::tooling::IncludeStyle::IncludeCategory)
+
+namespace llvm {
+namespace yaml {
+
+template <>
+struct MappingTraits<clang::tooling::IncludeStyle::IncludeCategory> {
+  static void mapping(IO &IO,
+                      clang::tooling::IncludeStyle::IncludeCategory &Category);
+};
+
+template <>
+struct ScalarEnumerationTraits<
+    clang::tooling::IncludeStyle::IncludeBlocksStyle> {
+  static void
+  enumeration(IO &IO, clang::tooling::IncludeStyle::IncludeBlocksStyle &Value);
+};
+
+} // namespace yaml
+} // namespace llvm
+
+#endif // LLVM_CLANG_TOOLING_INCLUSIONS_INCLUDESTYLE_H