Merge pull request #313 from wolfp/restat_missing_input

Do not reset restat_mtime if an input is missing

2 files changed, 55 insertions, 7 deletions

diff --git a/src/build.cc b/src/build.cc
index 65aa6a9..eed52ae 100644
--- a/src/build.cc
+++ b/src/build.cc
@@ -739,19 +739,13 @@ void Builder::FinishEdge(Edge* edge, bool success, const string& output) {
         for (vector<Node*>::iterator i = edge->inputs_.begin();
              i != edge->inputs_.end() - edge->order_only_deps_; ++i) {
           TimeStamp input_mtime = disk_interface_->Stat((*i)->path());
-          if (input_mtime == 0) {
-            restat_mtime = 0;
-            break;
-          }
           if (input_mtime > restat_mtime)
             restat_mtime = input_mtime;
         }
 
         if (restat_mtime != 0 && !edge->rule().depfile().empty()) {
           TimeStamp depfile_mtime = disk_interface_->Stat(edge->EvaluateDepFile());
-          if (depfile_mtime == 0)
-            restat_mtime = 0;
-          else if (depfile_mtime > restat_mtime)
+          if (depfile_mtime > restat_mtime)
             restat_mtime = depfile_mtime;
         }
 
diff --git a/src/build_test.cc b/src/build_test.cc
index 23f1909..a3f345b 100644
--- a/src/build_test.cc
+++ b/src/build_test.cc
@@ -802,6 +802,60 @@ TEST_F(BuildWithLogTest, RestatMissingFile) {
   ASSERT_EQ(1u, commands_ran_.size());
 }
 
+// Test scenario, in which an input file is removed, but output isn't changed
+// https://github.com/martine/ninja/issues/295
+TEST_F(BuildWithLogTest, RestatMissingInput) {
+  ASSERT_NO_FATAL_FAILURE(AssertParse(&state_,
+    "rule true\n"
+    "  command = true\n"
+    "  depfile = $out.d\n"
+    "  restat = 1\n"
+    "rule cc\n"
+    "  command = cc\n"
+    "build out1: true in\n"
+    "build out2: cc out1\n"));
+
+  // Create all necessary files
+  fs_.Create("in", now_, "");
+
+  // The implicit dependencies and the depfile itself 
+  // are newer than the output
+  TimeStamp restat_mtime = ++now_;
+  fs_.Create("out1.d", now_, "out1: will.be.deleted restat.file\n");
+  fs_.Create("will.be.deleted", now_, "");
+  fs_.Create("restat.file", now_, "");
+
+  // Run the build, out1 and out2 get built
+  string err;
+  EXPECT_TRUE(builder_.AddTarget("out2", &err));
+  ASSERT_EQ("", err);
+  EXPECT_TRUE(builder_.Build(&err));
+  ASSERT_EQ(2u, commands_ran_.size());
+
+  // See that an entry in the logfile is created, capturing
+  // the right mtime
+  BuildLog::LogEntry * log_entry = build_log_.LookupByOutput("out1");
+  ASSERT_TRUE(NULL != log_entry);
+  ASSERT_EQ(restat_mtime, log_entry->restat_mtime);
+
+  // Now remove a file, referenced from depfile, so that target becomes 
+  // dirty, but the output does not change
+  fs_.RemoveFile("will.be.deleted");
+  
+  // Trigger the build again - only out1 gets built
+  commands_ran_.clear();
+  state_.Reset();
+  EXPECT_TRUE(builder_.AddTarget("out2", &err));
+  ASSERT_EQ("", err);
+  EXPECT_TRUE(builder_.Build(&err));
+  ASSERT_EQ(1u, commands_ran_.size());
+
+  // Check that the logfile entry remains correctly set
+  log_entry = build_log_.LookupByOutput("out1");
+  ASSERT_TRUE(NULL != log_entry);
+  ASSERT_EQ(restat_mtime, log_entry->restat_mtime);
+}
+
 struct BuildDryRun : public BuildWithLogTest {
   BuildDryRun() {
     config_.dry_run = true;