Write top-level targets to the Ninja file in the alphabetical order

Fixes issue#238

3 files changed, 18 insertions, 7 deletions

diff --git a/src/dep.cc b/src/dep.cc
index d16f2d3..bf4c947 100644
--- a/src/dep.cc
+++ b/src/dep.cc
@@ -918,7 +918,12 @@ class DepBuilder {
   }
 
   Evaluator* ev_;
-  map<Symbol, RuleMerger> rules_;
+  struct TargetComp {
+    bool operator()(const Symbol& lhs, const Symbol& rhs) const {
+      return lhs.str() < rhs.str();
+    }
+  };
+  map<Symbol, RuleMerger, TargetComp> rules_;
   const unordered_map<Symbol, Vars*>& rule_vars_;
   unique_ptr<Vars> cur_rule_vars_;
 
diff --git a/testcase/build_once.mk b/testcase/build_once.mk
index ecb2a4e..792ae2b 100644
--- a/testcase/build_once.mk
+++ b/testcase/build_once.mk
@@ -1,7 +1,13 @@
 # expect protoc compile/link only once.
+
+# Caveat: this test relies on Make and Ninja updating 
+# the targets in the same order. Make's target update
+# order is depth first, Ninja's is the first lexically
+# updatable target. Caution should be taken as Kati reorders
+# targets.
 test: foo
 
-foo: foo.o bar.o
+foo: foo.o xbar.o
 	echo link $@ from $<
 
 %.o: %.c FORCE_DO_CMD
@@ -17,12 +23,12 @@ foo.c: foo.proto
 
 foo.proto:
 
-bar.c: | protoc
+xbar.c: | protoc
 
-bar.c: bar.proto
+xbar.c: xbar.proto
 	echo protoc $@ from $<
 
-bar.proto:
+xbar.proto:
 
 protoc: proto.o
 	echo link $@ from $<
diff --git a/testcase/curdir_implicit_rule.mk b/testcase/curdir_implicit_rule.mk
index 1f4ffaa..07df0ac 100644
--- a/testcase/curdir_implicit_rule.mk
+++ b/testcase/curdir_implicit_rule.mk
@@ -1,6 +1,6 @@
 srcdir := .
 
-test: foo.o bar.o
+test: foo.o xbar.o
 	echo linking $@ from $<
 
 %.o: $(srcdir)/%.c
@@ -9,5 +9,5 @@ test: foo.o bar.o
 $(srcdir)/foo.c:
 	echo source $@
 
-bar.c:
+xbar.c:
 	echo source $@