Auto-generate v8 version based on tags.

tools/push-to-trunk/generate_version.py

Index: tools/push-to-trunk/generate_version.py
diff --git a/tools/push-to-trunk/generate_version.py b/tools/push-to-trunk/generate_version.py
index b4a0221eae5c10224a18d79bf8067ca3df958177..28cd2033c935b397eb1b2b917aa54000ed057b22 100755
--- a/tools/push-to-trunk/generate_version.py
+++ b/tools/push-to-trunk/generate_version.py
@@ -19,6 +19,12 @@ CWD = os.path.abspath(
 VERSION_CC = os.path.join(CWD, "src", "version.cc")
 
 def main():
+  if len(sys.argv) != 2:
+    print "Error: Specify the output file path for version.cc"
+    return 1
+  version_out = sys.argv[1]
+  assert os.path.exists(os.path.dirname(version_out))
+
   tag = subprocess.check_output(
       "git describe --tags",
       shell=True,
@@ -50,21 +56,20 @@ def main():
     patch = "0"
 
   # Modify version.cc with the new values.
-  with open(VERSION_CC, "r") as f:
-    text = f.read()
   output = []
-  for line in text.split("\n"):
-    for definition, substitute in (
-        ("MAJOR_VERSION", major),
-        ("MINOR_VERSION", minor),
-        ("BUILD_NUMBER", build),
-        ("PATCH_LEVEL", patch),
-        ("IS_CANDIDATE_VERSION", candidate)):
-      if line.startswith("#define %s" % definition):
-        line =  re.sub("\d+$", substitute, line)
-    output.append(line)
-  with open(VERSION_CC, "w") as f:
-    f.write("\n".join(output))
+  with open(VERSION_CC, "r") as f:
+    for line in f:
+      for definition, substitute in (
+          ("MAJOR_VERSION", major),
+          ("MINOR_VERSION", minor),
+          ("BUILD_NUMBER", build),
+          ("PATCH_LEVEL", patch),
+          ("IS_CANDIDATE_VERSION", candidate)):
+        if line.startswith("#define %s" % definition):
+          line =  re.sub("\d+$", substitute, line)
+      output.append(line)
+  with open(version_out, "w") as f:
+    f.write("".join(output))
 
   # Log what was done.
   candidate_txt = " (candidate)" if candidate == "1" else ""