Maintain change log file directly on trunk branch in push-to-trunk.

tools/push-to-trunk/test_scripts.py

Index: tools/push-to-trunk/test_scripts.py
diff --git a/tools/push-to-trunk/test_scripts.py b/tools/push-to-trunk/test_scripts.py
index 207cac45e8531584fb233430b0264e146fd452b0..505cbda2949c9baecc290a778245194e2ea64d1f 100644
--- a/tools/push-to-trunk/test_scripts.py
+++ b/tools/push-to-trunk/test_scripts.py
@@ -643,7 +643,10 @@ Performance and stability improvements on all platforms."""
     TEST_CONFIG[CHANGELOG_FILE] = self.MakeEmptyTempFile()
     if not os.path.exists(TEST_CONFIG[CHROMIUM]):
       os.makedirs(TEST_CONFIG[CHROMIUM])
-    TextToFile("1999-04-05: Version 3.22.4", TEST_CONFIG[CHANGELOG_FILE])
+    old_change_log = """1999-04-05: Version 3.22.4
+
+        Performance and stability improvements on all platforms.\n"""
+    TextToFile(old_change_log, TEST_CONFIG[CHANGELOG_FILE])
     TextToFile("Some line\n   \"v8_revision\": \"123444\",\n  some line",
                  TEST_CONFIG[DEPS_FILE])
     os.environ["EDITOR"] = "vi"
@@ -660,6 +663,11 @@ Performance and stability improvements on all platforms."""
       version = FileToText(TEST_CONFIG[VERSION_FILE])
       self.assertTrue(re.search(r"#define BUILD_NUMBER\s+6", version))
 
+    def TrunkBranchSideEffects():
+      """On 'git co -b new_branch svn/trunk', the ChangLog will be reset to its
+      original content."""
+      TextToFile(old_change_log, TEST_CONFIG[CHANGELOG_FILE])
+
     def CheckSVNCommit():
       commit = FileToText(TEST_CONFIG[COMMITMSG_FILE])
       self.assertEquals(
@@ -675,6 +683,21 @@ Performance and stability improvements on all platforms.""", commit)
       self.assertTrue(re.search(r"#define PATCH_LEVEL\s+0", version))
       self.assertTrue(re.search(r"#define IS_CANDIDATE_VERSION\s+0", version))
 
+      # Check that the change log on the trunk branch got correctly modified.
+      change_log = FileToText(TEST_CONFIG[CHANGELOG_FILE])
+      self.assertEquals(
+"""1999-07-31: Version 3.22.5
+
+        Log text 1 (issue 321).
+
+        Performance and stability improvements on all platforms.
+
+
+1999-04-05: Version 3.22.4
+
+        Performance and stability improvements on all platforms.\n""",
+          change_log)
+
     force_flag = " -f" if not manual else ""
     review_suffix = "\n\nTBR=reviewer@chromium.org" if not manual else ""
     self.ExpectGit([
@@ -711,10 +734,14 @@ Performance and stability improvements on all platforms.""", commit)
       Git(("log -1 --format=%H --grep=\"Prepare push to trunk.  "
            "Now working on version 3.22.6.\""),
           "hash1\n"),
-      Git("diff --name-only svn/trunk hash1", "file1\nfile2\n"),
+      # The ChangeLog file will be one of the files with differences between
+      # trunk and bleeding edge.
+      Git("diff --name-only svn/trunk hash1",
+          "file1\n%s\nfile2\n" % TEST_CONFIG[CHANGELOG_FILE]),
       Git("diff svn/trunk hash1 file1 file2", "patch content"),
       Git("svn find-rev hash1", "123455\n"),
-      Git("checkout -b %s svn/trunk" % TEST_CONFIG[TRUNKBRANCH], ""),
+      Git("checkout -b %s svn/trunk" % TEST_CONFIG[TRUNKBRANCH], "",
+          cb=TrunkBranchSideEffects),
       Git("apply --index --reject \"%s\"" % TEST_CONFIG[PATCH_FILE], ""),
       Git("add \"%s\"" % TEST_CONFIG[VERSION_FILE], ""),
       Git("commit -aF \"%s\"" % TEST_CONFIG[COMMITMSG_FILE], "",