use DiskInterface to create the build directory

Fixes issue #392 (didn't handle creating nested build dirs right).

Moves MakeDir out of util.h; all code should go through
DiskInterface to simplify testing.  Moves ownership of the
DiskInterface into the client of the Builder, which also allows
removing some code that reached inside the object as well as
a minor leak.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/build.cc b/src/build.cc
index a1c94e4..6d1318c 100644
--- a/src/build.cc
+++ b/src/build.cc
@@ -552,9 +552,9 @@ struct DryRunCommandRunner : public CommandRunner {
   queue<Edge*> finished_;
 };
 
-Builder::Builder(State* state, const BuildConfig& config)
-    : state_(state), config_(config) {
-  disk_interface_ = new RealDiskInterface;
+Builder::Builder(State* state, const BuildConfig& config,
+                 DiskInterface* disk_interface)
+    : state_(state), config_(config), disk_interface_(disk_interface) {
   status_ = new BuildStatus(config);
   log_ = state->build_log_;
 }