[libclang] Introduce a new parsing option 'CXTranslationUnit_SingleFileParse' that puts preprocessor in a mode for parsing a single file only.

This is useful for parsing a single file, as a fast/inaccurate 'mode' that can still provide declarations from the file, like the classes and their methods.

llvm-svn: 305044

2 files changed, 34 insertions, 2 deletions

diff --git a/clang/tools/c-index-test/c-index-test.c b/clang/tools/c-index-test/c-index-test.c
index 31ad828a2f1..d25ae117a68 100644
--- a/clang/tools/c-index-test/c-index-test.c
+++ b/clang/tools/c-index-test/c-index-test.c
@@ -1850,6 +1850,34 @@ int perform_test_reparse_source(int argc, const char **argv, int trials,
   return result;
 }
 
+static int perform_single_file_parse(const char *filename) {
+  CXIndex Idx;
+  CXTranslationUnit TU;
+  enum CXErrorCode Err;
+  int result;
+
+  Idx = clang_createIndex(/* excludeDeclsFromPCH */1,
+                          /* displayDiagnostics=*/1);
+
+  Err = clang_parseTranslationUnit2(Idx, filename,
+                                    /*command_line_args=*/NULL,
+                                    /*num_command_line_args=*/0,
+                                    /*unsaved_files=*/NULL,
+                                    /*num_unsaved_files=*/0,
+                                    CXTranslationUnit_SingleFileParse, &TU);
+  if (Err != CXError_Success) {
+    fprintf(stderr, "Unable to load translation unit!\n");
+    describeLibclangFailure(Err);
+    clang_disposeIndex(Idx);
+    return 1;
+  }
+
+  result = perform_test_load(Idx, TU, /*filter=*/"all", /*prefix=*/NULL, FilteredPrintingVisitor, /*PostVisit=*/NULL,
+                             /*CommentSchemaFile=*/NULL);
+  clang_disposeIndex(Idx);
+  return result;
+}
+
 /******************************************************************************/
 /* Logic for testing clang_getCursor().                                       */
 /******************************************************************************/
@@ -4439,6 +4467,8 @@ int cindextest_main(int argc, const char **argv) {
       return perform_test_load_source(argc - 3, argv + 3, argv[2], I,
                                       postVisit);
   }
+  else if (argc >= 3 && strcmp(argv[1], "-single-file-parse") == 0)
+    return perform_single_file_parse(argv[2]);
   else if (argc >= 4 && strcmp(argv[1], "-test-file-scan") == 0)
     return perform_file_scan(argv[2], argv[3],
                              argc >= 5 ? argv[4] : 0);
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 2d92de19d99..1ccf6cbd328 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -3300,12 +3300,14 @@ clang_parseTranslationUnit_Impl(CXIndex CIdx, const char *source_filename,
       options & CXTranslationUnit_CreatePreambleOnFirstParse;
   // FIXME: Add a flag for modules.
   TranslationUnitKind TUKind
-    = (options & CXTranslationUnit_Incomplete)? TU_Prefix : TU_Complete;
+    = (options & (CXTranslationUnit_Incomplete |
+                  CXTranslationUnit_SingleFileParse))? TU_Prefix : TU_Complete;
   bool CacheCodeCompletionResults
     = options & CXTranslationUnit_CacheCompletionResults;
   bool IncludeBriefCommentsInCodeCompletion
     = options & CXTranslationUnit_IncludeBriefCommentsInCodeCompletion;
   bool SkipFunctionBodies = options & CXTranslationUnit_SkipFunctionBodies;
+  bool SingleFileParse = options & CXTranslationUnit_SingleFileParse;
   bool ForSerialization = options & CXTranslationUnit_ForSerialization;
 
   // Configure the diagnostics.
@@ -3390,7 +3392,7 @@ clang_parseTranslationUnit_Impl(CXIndex CIdx, const char *source_filename,
       /*CaptureDiagnostics=*/true, *RemappedFiles.get(),
       /*RemappedFilesKeepOriginalName=*/true, PrecompilePreambleAfterNParses,
       TUKind, CacheCodeCompletionResults, IncludeBriefCommentsInCodeCompletion,
-      /*AllowPCHWithCompilerErrors=*/true, SkipFunctionBodies,
+      /*AllowPCHWithCompilerErrors=*/true, SkipFunctionBodies, SingleFileParse,
       /*UserFilesAreVolatile=*/true, ForSerialization,
       CXXIdx->getPCHContainerOperations()->getRawReader().getFormat(),
       &ErrUnit));