Replace the -code-completion-dump option with

  -code-completion-at=filename:line:column

which performs code completion at the specified location by truncating
the file at that position and enabling code completion. This approach
makes it possible to run multiple tests from a single test file, and
gives a more natural command-line interface.

llvm-svn: 82571

3 files changed, 100 insertions, 19 deletions

diff --git a/clang/lib/Basic/SourceManager.cpp b/clang/lib/Basic/SourceManager.cpp
index d1c47095a24..962cb4c42a8 100644
--- a/clang/lib/Basic/SourceManager.cpp
+++ b/clang/lib/Basic/SourceManager.cpp
@@ -41,9 +41,10 @@ unsigned ContentCache::getSizeBytesMapped() const {
 /// getSize - Returns the size of the content encapsulated by this ContentCache.
 ///  This can be the size of the source file or the size of an arbitrary
 ///  scratch buffer.  If the ContentCache encapsulates a source file, that
-///  file is not lazily brought in from disk to satisfy this query.
+///  file is not lazily brought in from disk to satisfy this query unless it
+///  needs to be truncated due to a truncateAt() call.
 unsigned ContentCache::getSize() const {
-  return Entry ? Entry->getSize() : Buffer->getBufferSize();
+  return Buffer ? Buffer->getBufferSize() : Entry->getSize();
 }
 
 const llvm::MemoryBuffer *ContentCache::getBuffer() const {
@@ -52,10 +53,54 @@ const llvm::MemoryBuffer *ContentCache::getBuffer() const {
     // FIXME: Should we support a way to not have to do this check over
     //   and over if we cannot open the file?
     Buffer = MemoryBuffer::getFile(Entry->getName(), 0, Entry->getSize());
+    if (isTruncated())
+      const_cast<ContentCache *>(this)->truncateAt(TruncateAtLine, 
+                                                   TruncateAtColumn);
   }
   return Buffer;
 }
 
+void ContentCache::truncateAt(unsigned Line, unsigned Column) {
+  TruncateAtLine = Line;
+  TruncateAtColumn = Column;
+  
+  if (!isTruncated() || !Buffer)
+    return;
+  
+  // Find the byte position of the truncation point.
+  const char *Position = Buffer->getBufferStart();
+  for (unsigned Line = 1; Line < TruncateAtLine; ++Line) {
+    for (; *Position; ++Position) {
+      if (*Position != '\r' && *Position != '\n')
+        continue;
+      
+      // Eat \r\n or \n\r as a single line.
+      if ((Position[1] == '\r' || Position[1] == '\n') &&
+          Position[0] != Position[1])
+        ++Position;
+      ++Position;
+      break;
+    }
+  }
+  
+  for (unsigned Column = 1; Column < TruncateAtColumn; ++Column, ++Position) {
+    if (!*Position)
+      break;
+    
+    if (*Position == '\t')
+      Column += 7;
+  }
+  
+  // Truncate the buffer.
+  if (Position != Buffer->getBufferEnd()) {
+    MemoryBuffer *TruncatedBuffer 
+      = MemoryBuffer::getMemBufferCopy(Buffer->getBufferStart(), Position, 
+                                       Buffer->getBufferIdentifier());
+    delete Buffer;
+    Buffer = TruncatedBuffer;
+  }
+}
+
 unsigned LineTableInfo::getLineTableFilenameID(const char *Ptr, unsigned Len) {
   // Look up the filename in the string table, returning the pre-existing value
   // if it exists.
@@ -287,6 +332,16 @@ SourceManager::getOrCreateContentCache(const FileEntry *FileEnt) {
   EntryAlign = std::max(8U, EntryAlign);
   Entry = ContentCacheAlloc.Allocate<ContentCache>(1, EntryAlign);
   new (Entry) ContentCache(FileEnt);
+  
+  if (FileEnt == TruncateFile) {
+    // If we had queued up a file truncation request, perform the truncation
+    // now.
+    Entry->truncateAt(TruncateAtLine, TruncateAtColumn);
+    TruncateFile = 0;
+    TruncateAtLine = 0;
+    TruncateAtColumn = 0;
+  }
+  
   return Entry;
 }
 
@@ -1058,6 +1113,28 @@ bool SourceManager::isBeforeInTranslationUnit(SourceLocation LHS,
   }
 }
 
+void SourceManager::truncateFileAt(const FileEntry *Entry, unsigned Line, 
+                                   unsigned Column) {
+  llvm::DenseMap<const FileEntry*, SrcMgr::ContentCache*>::iterator FI
+     = FileInfos.find(Entry);
+  if (FI != FileInfos.end()) {
+    FI->second->truncateAt(Line, Column);
+    return;
+  }
+  
+  // We cannot perform the truncation until we actually see the file, so
+  // save the truncation information.
+  assert(TruncateFile == 0 && "Can't queue up multiple file truncations!");
+  TruncateFile = Entry;
+  TruncateAtLine = Line;
+  TruncateAtColumn = Column;
+}
+
+/// \brief Determine whether this file was truncated.
+bool SourceManager::isTruncatedFile(FileID FID) const {
+  return getSLocEntry(FID).getFile().getContentCache()->isTruncated();
+}
+
 /// PrintStats - Print statistics to stderr.
 ///
 void SourceManager::PrintStats() const {
diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index 74ac55cf2eb..0f01155a8f2 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -101,12 +101,16 @@ Lexer::Lexer(FileID FID, Preprocessor &PP)
     Features(PP.getLangOptions()) {
 
   const llvm::MemoryBuffer *InputFile = PP.getSourceManager().getBuffer(FID);
-
+  
   InitLexer(InputFile->getBufferStart(), InputFile->getBufferStart(),
             InputFile->getBufferEnd());
 
   // Default to keeping comments if the preprocessor wants them.
   SetCommentRetentionState(PP.getCommentRetentionState());
+      
+  // If the input file is truncated, the EOF is a code-completion token.
+  if (PP.getSourceManager().isTruncatedFile(FID))
+    IsEofCodeCompletion = true;
 }
 
 /// Lexer constructor - Create a new raw lexer object.  This object is only
@@ -1323,15 +1327,23 @@ bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
   // unterminated #if and missing newline.
 
   if (IsEofCodeCompletion) {
-    // We're at the end of the file, but we've been asked to conside the
-    // end of the file to be a code-completion token. Return the
-    // code-completion token.
-    Result.startToken();
-    FormTokenWithChars(Result, CurPtr, tok::code_completion);
+    bool isIntendedFile = true;
+    if (PP && FileLoc.isFileID()) {
+      SourceManager &SM = PP->getSourceManager();
+      isIntendedFile = SM.isTruncatedFile(SM.getFileID(FileLoc));
+    }
     
-    // Only do the eof -> code_completion translation once.
-    IsEofCodeCompletion = false;
-    return true;
+    if (isIntendedFile) {
+      // We're at the end of the file, but we've been asked to consider the
+      // end of the file to be a code-completion token. Return the
+      // code-completion token.
+      Result.startToken();
+      FormTokenWithChars(Result, CurPtr, tok::code_completion);
+      
+      // Only do the eof -> code_completion translation once.
+      IsEofCodeCompletion = false;
+      return true;
+    }
   }
   
   // If we are in a #if directive, emit an error.
diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 4e522cbb8a4..bfa090a09e8 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -71,7 +71,6 @@ Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
   // Macro expansion is enabled.
   DisableMacroExpansion = false;
   InMacroArgs = false;
-  IsMainFileEofCodeCompletion = false;
   NumCachedTokenLexers = 0;
 
   CachedLexPos = 0;
@@ -369,13 +368,6 @@ void Preprocessor::EnterMainSourceFile() {
   // Enter the main file source buffer.
   EnterSourceFile(MainFileID, 0);
 
-  if (IsMainFileEofCodeCompletion) {
-    // Tell our newly-created lexer that it should treat its end-of-file as
-    // a code-completion token.
-    IsMainFileEofCodeCompletion = false;
-    static_cast<Lexer *>(getCurrentFileLexer())->SetEofIsCodeCompletion();
-  }
-  
   // Tell the header info that the main file was entered.  If the file is later
   // #imported, it won't be re-entered.
   if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))