Add a test that fails if a rule updates it output file but fails

https://groups.google.com/forum/#!msg/ninja-build/YQuGNrECI-4/ti-lAs9SPv8J
discusses a case where an rule updates its output file and then
fails.  The next run of ninja considers the ouptut file clean
and doesn't rebuild it.  Add a test for this case, which currently
fails.

3 files changed, 59 insertions, 2 deletions

diff --git a/src/build.cc b/src/build.cc
index a0c7ec8..44d0663 100644
--- a/src/build.cc
+++ b/src/build.cc
@@ -275,6 +275,13 @@ void BuildStatus::PrintStatus(Edge* edge, EdgeStatus status) {
 
 Plan::Plan() : command_edges_(0), wanted_edges_(0) {}
 
+void Plan::Reset() {
+  command_edges_ = 0;
+  wanted_edges_ = 0;
+  ready_.clear();
+  want_.clear();
+}
+
 bool Plan::AddTarget(Node* node, string* err) {
   vector<Node*> stack;
   return AddSubTarget(node, &stack, err);
diff --git a/src/build.h b/src/build.h
index 66ce607..f97d67e 100644
--- a/src/build.h
+++ b/src/build.h
@@ -71,6 +71,9 @@ struct Plan {
   /// Number of edges with commands to run.
   int command_edge_count() const { return command_edges_; }
 
+  /// Reset state.  Clears want and ready sets.
+  void Reset();
+
 private:
   bool AddSubTarget(Node* node, vector<Node*>* stack, string* err);
   bool CheckDependencyCycle(Node* node, const vector<Node*>& stack,
diff --git a/src/build_test.cc b/src/build_test.cc
index 640e1b0..d617143 100644
--- a/src/build_test.cc
+++ b/src/build_test.cc
@@ -608,7 +608,8 @@ bool FakeCommandRunner::StartCommand(Edge* edge) {
       edge->rule().name() == "cat_rsp_out" ||
       edge->rule().name() == "cc" ||
       edge->rule().name() == "touch" ||
-      edge->rule().name() == "touch-interrupt") {
+      edge->rule().name() == "touch-interrupt" ||
+      edge->rule().name() == "touch-fail-tick2") {
     for (vector<Node*>::iterator out = edge->outputs_.begin();
          out != edge->outputs_.end(); ++out) {
       fs_->Create((*out)->path(), "");
@@ -649,7 +650,8 @@ bool FakeCommandRunner::WaitForCommand(Result* result) {
     return true;
   }
 
-  if (edge->rule().name() == "fail")
+  if (edge->rule().name() == "fail" ||
+      (edge->rule().name() == "touch-fail-tick2" && fs_->now_ == 2))
     result->status = ExitFailure;
   else
     result->status = ExitSuccess;
@@ -1258,6 +1260,51 @@ TEST_F(BuildWithLogTest, NotInLogButOnDisk) {
   EXPECT_TRUE(builder_.AlreadyUpToDate());
 }
 
+TEST_F(BuildWithLogTest, RebuildAfterFailure) {
+  ASSERT_NO_FATAL_FAILURE(AssertParse(&state_,
+"rule touch-fail-tick2\n"
+"  command = touch-fail-tick2\n"
+"build out1: touch-fail-tick2 in\n"));
+
+  string err;
+
+  fs_.Create("in", "");
+
+  // Run once successfully to get out1 in the log
+  EXPECT_TRUE(builder_.AddTarget("out1", &err));
+  EXPECT_TRUE(builder_.Build(&err));
+  EXPECT_EQ("", err);
+  EXPECT_EQ(1u, command_runner_.commands_ran_.size());
+
+  command_runner_.commands_ran_.clear();
+  state_.Reset();
+  builder_.Cleanup();
+  builder_.plan_.Reset();
+
+  fs_.Tick();
+  fs_.Create("in", "");
+
+  // Run again with a failure that updates the output file timestamp
+  EXPECT_TRUE(builder_.AddTarget("out1", &err));
+  EXPECT_FALSE(builder_.Build(&err));
+  EXPECT_EQ("subcommand failed", err);
+  EXPECT_EQ(1u, command_runner_.commands_ran_.size());
+
+  command_runner_.commands_ran_.clear();
+  state_.Reset();
+  builder_.Cleanup();
+  builder_.plan_.Reset();
+
+  fs_.Tick();
+
+  // Run again, should rerun even though the output file is up to date on disk
+  EXPECT_TRUE(builder_.AddTarget("out1", &err));
+  EXPECT_FALSE(builder_.AlreadyUpToDate());
+  EXPECT_TRUE(builder_.Build(&err));
+  EXPECT_EQ(1u, command_runner_.commands_ran_.size());
+  EXPECT_EQ("", err);
+}
+
 TEST_F(BuildWithLogTest, RestatTest) {
   ASSERT_NO_FATAL_FAILURE(AssertParse(&state_,
 "rule true\n"