Move duplicated code into a helper function.

Author: nico

src/deps_log.cc

@@ -325,18 +325,8 @@ bool DepsLog::Recompact(const string& path, string* err) {
     Deps* deps = deps_[old_id];
     if (!deps) continue;  // If nodes_[old_id] is a leaf, it has no deps.
 
-    Node* n = nodes_[old_id];
-    Edge* e = n->in_edge();
-    // FIXME: move this condition to a helper: (also used in src/ninja.cc)
-    if (!e || e->GetBinding("deps").empty()) {
-      // Skip entries that don't have in-edges or whose edges don't have a
-      // "deps" attribute. They were in the deps log from previous builds, but
-      // the the files they were for were removed from the build and their deps
-      // entries are no longer needed.
-      // (Without the check for "deps", a chain of two or more nodes that each
-      // had deps wouldn't be collected in a single recompaction.)
+    if (!IsDepsEntryLiveFor(nodes_[old_id]))
       continue;
-    }
 
     if (!new_log.RecordDeps(nodes_[old_id], deps->mtime,
                             deps->node_count, deps->nodes)) {
@@ -364,6 +354,16 @@ bool DepsLog::Recompact(const string& path, string* err) {
   return true;
 }
 
+bool DepsLog::IsDepsEntryLiveFor(Node* node) {
+  // Skip entries that don't have in-edges or whose edges don't have a
+  // "deps" attribute. They were in the deps log from previous builds, but
+  // the the files they were for were removed from the build and their deps
+  // entries are no longer needed.
+  // (Without the check for "deps", a chain of two or more nodes that each
+  // had deps wouldn't be collected in a single recompaction.)
+  return node->in_edge() && !node->in_edge()->GetBinding("deps").empty();
+}
+
 bool DepsLog::UpdateDeps(int out_id, Deps* deps) {
   if (out_id >= (int)deps_.size())
     deps_.resize(out_id + 1);

src/deps_log.h

@@ -88,6 +88,14 @@ struct DepsLog {
   /// Rewrite the known log entries, throwing away old data.
   bool Recompact(const string& path, string* err);
 
+  /// Returns if the deps entry for a node is still reachable from the manifest.
+  ///
+  /// The deps log can contain deps entries for files that were built in the
+  /// past but are no longer part of the manifest.  This function returns if
+  /// this is the case for a given node.  This function is slow, don't call
+  /// it from code that runs on every build.
+  bool IsDepsEntryLiveFor(Node* node);
+
   /// Used for tests.
   const vector<Node*>& nodes() const { return nodes_; }
   const vector<Deps*>& deps() const { return deps_; }

src/ninja.cc

@@ -449,9 +449,7 @@ int NinjaMain::ToolDeps(int argc, char** argv) {
   if (argc == 0) {
     for (vector<Node*>::const_iterator ni = deps_log_.nodes().begin();
          ni != deps_log_.nodes().end(); ++ni) {
-      // Only query for targets with an incoming edge and deps
-      Edge* e = (*ni)->in_edge();
-      if (e && !e->GetBinding("deps").empty())
+      if (deps_log_.IsDepsEntryLiveFor(*ni))
         nodes.push_back(*ni);
     }
   } else {