From 0ec15eeb09c5456f6a16063250516cdf426c4905 Mon Sep 17 00:00:00 2001
From: Avery Pennarun <apenwarr@gmail.com>
Date: Wed, 24 Nov 2010 03:37:30 -0800
Subject: [PATCH] If a target's .do file disappears, don't forget to stamp it.

If a file previously was generated but now isn't (ie. its .do file
disappears), we would never re-stamp that target, and so all its
dependencies would rebuild continually.
---
 builder.py         |  1 +
 t/deps/.gitignore  |  2 ++
 t/deps/clean.do    |  3 ++-
 t/deps/genfile1.do |  2 ++
 t/deps/gentest.do  | 20 ++++++++++++++++++++
 t/deps/test.do     |  3 +--
 6 files changed, 28 insertions(+), 3 deletions(-)
 create mode 100644 t/deps/genfile1.do
 create mode 100644 t/deps/gentest.do

diff --git a/builder.py b/builder.py
index 783d6e4..febfeb6 100644
--- a/builder.py
+++ b/builder.py
@@ -70,6 +70,7 @@ class BuildJob:
         (dofile, basename, ext) = _find_do_file(t)
         if not dofile:
             if os.path.exists(t):
+                state.stamp(t)
                 return self._after2(0)
             else:
                 err('no rule to make %r\n' % t)
diff --git a/t/deps/.gitignore b/t/deps/.gitignore
index efb409b..4dfb618 100644
--- a/t/deps/.gitignore
+++ b/t/deps/.gitignore
@@ -2,3 +2,5 @@ t1a
 t2.count
 overwrite
 overwrite[123]
+genfile2
+genfile.log
\ No newline at end of file
diff --git a/t/deps/clean.do b/t/deps/clean.do
index fc9a0cc..a1d9f1e 100644
--- a/t/deps/clean.do
+++ b/t/deps/clean.do
@@ -1,3 +1,4 @@
 redo basic/clean dirtest/clean
-rm -f *~ .*~ *.count t1a overwrite overwrite[123]
+rm -f *~ .*~ *.count t1a overwrite overwrite[123] genfile2 genfile.log
+
 
diff --git a/t/deps/genfile1.do b/t/deps/genfile1.do
new file mode 100644
index 0000000..2f85915
--- /dev/null
+++ b/t/deps/genfile1.do
@@ -0,0 +1,2 @@
+redo-ifchange genfile2
+echo $$ >>genfile.log
diff --git a/t/deps/gentest.do b/t/deps/gentest.do
new file mode 100644
index 0000000..5b6772e
--- /dev/null
+++ b/t/deps/gentest.do
@@ -0,0 +1,20 @@
+rm -f genfile2 genfile2.do genfile.log
+
+echo echo hello >genfile2.do
+. ../flush-cache.sh
+redo genfile1
+
+# this will cause a rebuild:
+#      genfile1 depends on genfile2 depends on genfile2.do
+rm -f genfile2.do
+. ../flush-cache.sh
+redo-ifchange genfile1
+
+# but genfile2.do was gone last time, so genfile2 no longer depends on it.
+# thus, it can be considered up-to-date.  Prior versions of redo had a bug
+# where the dependency on genfile2.do was never dropped.
+. ../flush-cache.sh
+redo-ifchange genfile1
+
+COUNT=$(wc -l <genfile.log)
+[ "$COUNT" = 2 ] || exit 77
diff --git a/t/deps/test.do b/t/deps/test.do
index 34ccbe9..2815253 100644
--- a/t/deps/test.do
+++ b/t/deps/test.do
@@ -1,2 +1 @@
-redo test1 test2 ifchange-fail overwrite basic/test dirtest/test
-
+redo test1 test2 ifchange-fail overwrite gentest basic/test dirtest/test
\ No newline at end of file