Clang: Add clang query

Clang query is mechanism to use AST matcher to search for code. Think
about regular expression but in the context of AST. So you get a semantic
search tool for C++.

Change-Id: I72e882c5b53a0c52f352a3664847c4c3e4f6fc2e
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/tools/clangrefactoringbackend/source/sourcelocationsutils.h

@@ -26,6 +26,7 @@
 #pragma once
 
 #include <sourcelocationscontainer.h>
+#include <sourcerangescontainer.h>
 
 #if defined(__GNUC__)
 #pragma GCC diagnostic push
@@ -40,6 +41,8 @@
 #pragma GCC diagnostic pop
 #endif
 
+#include <cctype>
+
 namespace ClangBackEnd {
 
 inline
@@ -65,6 +68,75 @@ Utils::SmallString fromNativePath(Container container)
     return path;
 }
 
+inline Utils::SmallString getSourceText(const clang::FullSourceLoc &startFullSourceLocation,
+                                        uint startOffset,
+                                        uint endOffset)
+{
+    auto startBuffer = startFullSourceLocation.getBufferData();
+    const auto bufferSize = endOffset - startOffset;
+
+    return Utils::SmallString(startBuffer.data() + startOffset, bufferSize + 1);
+}
+
+inline void makePrintable(Utils::SmallString &text)
+{
+    text.replace("\n", " ");
+    text.replace("\t", " ");
+
+    auto end = std::unique(text.begin(), text.end(), [](char l, char r){
+        return std::isspace(l) && std::isspace(r) && l == r;
+    });
+    text.resize(std::distance(text.begin(), end));
+}
+
+inline void appendSourceRangeToSourceRangesContainer(
+        const clang::SourceRange &sourceRange,
+        ClangBackEnd::SourceRangesContainer &sourceRangesContainer,
+        const clang::SourceManager &sourceManager)
+{
+    clang::FullSourceLoc startFullSourceLocation(sourceRange.getBegin(), sourceManager);
+    clang::FullSourceLoc endFullSourceLocation(sourceRange.getEnd(), sourceManager);
+    if (startFullSourceLocation.isFileID() && endFullSourceLocation.isFileID()) {
+        const auto startDecomposedLoction = startFullSourceLocation.getDecomposedLoc();
+        const auto endDecomposedLoction = endFullSourceLocation.getDecomposedLoc();
+        const auto fileId = startDecomposedLoction.first;
+        const auto startOffset = startDecomposedLoction.second;
+        const auto endOffset = endDecomposedLoction.second;
+        const auto fileEntry = sourceManager.getFileEntryForID(fileId);
+        auto filePath = absolutePath(fileEntry->getName());
+        const auto fileName = llvm::sys::path::filename(filePath);
+        llvm::sys::path::remove_filename(filePath);
+        Utils::SmallString content = getSourceText(startFullSourceLocation,
+                                                   startOffset,
+                                                   endOffset);
+        makePrintable(content);
+
+        sourceRangesContainer.insertFilePath(fileId.getHashValue(),
+                                             fromNativePath(filePath),
+                                             fromNativePath(fileName));
+        sourceRangesContainer.insertSourceRange(fileId.getHashValue(),
+                                                startFullSourceLocation.getSpellingLineNumber(),
+                                                startFullSourceLocation.getSpellingColumnNumber(),
+                                                startOffset,
+                                                endFullSourceLocation.getSpellingLineNumber(),
+                                                endFullSourceLocation.getSpellingColumnNumber(),
+                                                endOffset,
+                                                std::move(content));
+    }
+}
+
+inline
+void appendSourceRangesToSourceRangesContainer(
+        ClangBackEnd::SourceRangesContainer &sourceRangesContainer,
+        const std::vector<clang::SourceRange> &sourceRanges,
+        const clang::SourceManager &sourceManager)
+{
+    sourceRangesContainer.reserve(sourceRanges.size());
+
+    for (const auto &sourceRange : sourceRanges)
+        appendSourceRangeToSourceRangesContainer(sourceRange, sourceRangesContainer, sourceManager);
+}
+
 inline
 void appendSourceLocationsToSourceLocationsContainer(
         ClangBackEnd::SourceLocationsContainer &sourceLocationsContainer,
@@ -75,10 +147,12 @@ void appendSourceLocationsToSourceLocationsContainer(
 
     for (const auto &sourceLocation : sourceLocations) {
         clang::FullSourceLoc fullSourceLocation(sourceLocation, sourceManager);
-        auto fileId = fullSourceLocation.getFileID();
-        auto fileEntry = sourceManager.getFileEntryForID(fileId);
+        const auto decomposedLoction = fullSourceLocation.getDecomposedLoc();
+        const auto fileId = decomposedLoction.first;
+        const auto offset = decomposedLoction.second;
+        const auto fileEntry = sourceManager.getFileEntryForID(fileId);
         auto filePath = absolutePath(fileEntry->getName());
-        auto fileName = llvm::sys::path::filename(filePath);
+        const auto fileName = llvm::sys::path::filename(filePath);
         llvm::sys::path::remove_filename(filePath);
 
         sourceLocationsContainer.insertFilePath(fileId.getHashValue(),
@@ -86,8 +160,11 @@ void appendSourceLocationsToSourceLocationsContainer(
                                                 fromNativePath(fileName));
         sourceLocationsContainer.insertSourceLocation(fileId.getHashValue(),
                                                       fullSourceLocation.getSpellingLineNumber(),
-                                                      fullSourceLocation.getSpellingColumnNumber());
+                                                      fullSourceLocation.getSpellingColumnNumber(),
+                                                      offset);
     }
 }
 
+
+
 } // namespace ClangBackEnd