AutoMoc: do not scan files twice

We scanned files for the Q_OBJECT macro and then again to find
moc_XXX.cpp includes. This can be done in one pass.

Change-Id: I3b14be2a922ce244730b3ce21e7803c605ba59be
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>

2 files changed, 24 insertions, 30 deletions

diff --git a/src/lib/buildgraph/automoc.cpp b/src/lib/buildgraph/automoc.cpp
index 1c9374be8..40c798962 100644
--- a/src/lib/buildgraph/automoc.cpp
+++ b/src/lib/buildgraph/automoc.cpp
@@ -188,37 +188,21 @@ void AutoMoc::scan(Artifact *artifact, FileType fileType, bool &hasQObjectMacro,
     hasQObjectMacro = false;
 
     foreach (ScannerPlugin *scanner, fileType == HppFileType ? hppScanners() : cppScanners()) {
-        void *opaq = scanner->open(artifact->filePath().utf16(), ScanForFileTagsFlag);
-        if (!opaq || !scanner->additionalFileTags)
-            continue;
-
-        // HACK: misuse the file dependency scanner as provider for file tags
-        int length = 0;
-        const char **szFileTagsFromScanner = scanner->additionalFileTags(opaq, &length);
-        if (szFileTagsFromScanner && length > 0) {
-            for (int i=length; --i >= 0;) {
-                artifact->fileTags.insert(szFileTagsFromScanner[i]);
-                if (m_logger.traceEnabled())
-                    m_logger.qbsTrace() << "[AUTOMOC] finds Q_OBJECT macro";
-                const QByteArray fileTagFromScanner
-                        = QByteArray::fromRawData(szFileTagsFromScanner[i],
-                                                  qstrlen(szFileTagsFromScanner[i]));
-                if (fileTagFromScanner.startsWith("moc"))
-                    hasQObjectMacro = true;
-            }
-        }
-
-        scanner->close(opaq);
-
-        ScanResultCache::Result scanResult;
-        if (m_scanResultCache)
-            scanResult = m_scanResultCache->value(artifact->filePath());
+        ScanResultCache::Result scanResult = m_scanResultCache->value(artifact->filePath());
         if (!scanResult.valid) {
             scanResult.valid = true;
-            opaq = scanner->open(artifact->filePath().utf16(), ScanForDependenciesFlag);
-            if (!opaq)
+            void *opaq = scanner->open(artifact->filePath().utf16(),
+                                       ScanForDependenciesFlag | ScanForFileTagsFlag);
+            if (!opaq || !scanner->additionalFileTags)
                 continue;
 
+            int length = 0;
+            const char **szFileTagsFromScanner = scanner->additionalFileTags(opaq, &length);
+            if (szFileTagsFromScanner && length > 0) {
+                for (int i = length; --i >= 0;)
+                    scanResult.additionalFileTags += szFileTagsFromScanner[i];
+            }
+
             forever {
                 int flags = 0;
                 const char *szOutFilePath = scanner->next(opaq, &length, &flags);
@@ -232,8 +216,16 @@ void AutoMoc::scan(Artifact *artifact, FileType fileType, bool &hasQObjectMacro,
             }
 
             scanner->close(opaq);
-            if (m_scanResultCache)
-                m_scanResultCache->insert(artifact->filePath(), scanResult);
+            m_scanResultCache->insert(artifact->filePath(), scanResult);
+        }
+
+        foreach (const FileTag &tag, scanResult.additionalFileTags) {
+            artifact->fileTags.insert(tag);
+            if (tag.name().startsWith("moc")) {
+                hasQObjectMacro = true;
+                if (m_logger.traceEnabled())
+                    m_logger.qbsTrace() << "[AUTOMOC] finds Q_OBJECT macro";
+            }
         }
 
         foreach (const ScanResultCache::Dependency &dependency, scanResult.deps) {
diff --git a/src/lib/buildgraph/scanresultcache.h b/src/lib/buildgraph/scanresultcache.h
index 922141be5..d71f66ccf 100644
--- a/src/lib/buildgraph/scanresultcache.h
+++ b/src/lib/buildgraph/scanresultcache.h
@@ -30,8 +30,9 @@
 #ifndef QBS_SCANRESULTCACHE_H
 #define QBS_SCANRESULTCACHE_H
 
+#include <language/filetags.h>
+
 #include <QHash>
-#include <QSet>
 #include <QString>
 #include <QVector>
 
@@ -68,6 +69,7 @@ public:
         {}
 
         QVector<Dependency> deps;
+        FileTags additionalFileTags;
         bool valid;
     };