Bug 1454831 - Generate nsCSSPropertyID.h from data file directly. r=emilio

MozReview-Commit-ID: CcX2uzgjWFo

layout/style/GenerateCSSPropertyID.py

@@ -0,0 +1,35 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import string
+
+def generate(output, template, dataFile):
+    with open(template, "r") as f:
+        template = string.Template(f.read())
+    with open(dataFile, "r") as f:
+        data = eval(f.read())
+
+    longhand_count = 0
+    shorthand_count = 0
+    alias_count = 0
+    property_ids = []
+    for name, method, id, flags, pref, prototype in data:
+        if prototype != "alias":
+            if prototype == "longhand":
+                assert shorthand_count == 0
+                longhand_count += 1
+            else:
+                assert alias_count == 0
+                shorthand_count += 1
+            property_ids.append("eCSSProperty_{}".format(id))
+        else:
+            alias_count += 1
+            property_ids.append("eCSSPropertyAlias_{}".format(id[0]))
+
+    output.write("/* THIS IS AN AUTOGENERATED FILE.  DO NOT EDIT */\n\n")
+    output.write(template.substitute({
+        "property_ids": "\n".join("  {},".format(p) for p in property_ids),
+        "longhand_count": property_ids[longhand_count],
+        "shorthand_count": property_ids[longhand_count + shorthand_count],
+    }))