Bug 1662254 - Emit input filename in files generated for static prefs to make it easier to track backwards to a pref via searchfox r=KrisWright

Differential Revision: https://phabricator.services.mozilla.com/D94794

modules/libpref/init/generate_static_pref_list.py

@@ -57,7 +57,7 @@ RUST_TYPES = {
     "float": "f32",
 }
 
-FIRST_LINE = "// This file was generated by generate_static_pref_list.py. DO NOT EDIT."
+HEADER_LINE = "// This file was generated by generate_static_pref_list.py from {input_filename}. DO NOT EDIT."
 
 MIRROR_TEMPLATES = {
     "never": """\
@@ -222,19 +222,21 @@ def check_pref_list(pref_list):
         prev_pref = pref
 
 
-def generate_code(pref_list):
+def generate_code(pref_list, input_filename):
     check_pref_list(pref_list)
 
+    first_line = HEADER_LINE.format(input_filename=input_filename)
+
     # The required includes for StaticPrefs_<group>.h.
     includes = defaultdict(set)
 
     # StaticPrefList_<group>.h contains all the pref definitions for this
     # group.
-    static_pref_list_group_h = defaultdict(lambda: [FIRST_LINE, ""])
+    static_pref_list_group_h = defaultdict(lambda: [first_line, ""])
 
     # StaticPrefsCGetters.cpp contains C getters for all the mirrored prefs,
     # for use by Rust code.
-    static_prefs_c_getters_cpp = [FIRST_LINE, ""]
+    static_prefs_c_getters_cpp = [first_line, ""]
 
     # static_prefs.rs contains C getter declarations and a macro.
     static_prefs_rs_decls = []
@@ -310,7 +312,7 @@ def generate_code(pref_list):
 
     # StaticPrefListAll.h contains one `#include "mozilla/StaticPrefList_X.h`
     # line per pref group.
-    static_pref_list_all_h = [FIRST_LINE, ""]
+    static_pref_list_all_h = [first_line, ""]
     static_pref_list_all_h.extend(
         '#include "mozilla/StaticPrefList_{}.h"'.format(group)
         for group in sorted(static_pref_list_group_h)
@@ -319,7 +321,7 @@ def generate_code(pref_list):
 
     # StaticPrefsAll.h contains one `#include "mozilla/StaticPrefs_X.h` line per
     # pref group.
-    static_prefs_all_h = [FIRST_LINE, ""]
+    static_prefs_all_h = [first_line, ""]
     static_prefs_all_h.extend(
         '#include "mozilla/StaticPrefs_{}.h"'.format(group)
         for group in sorted(static_pref_list_group_h)
@@ -330,7 +332,7 @@ def generate_code(pref_list):
     # used directly by application code.
     static_prefs_group_h = defaultdict(list)
     for group in sorted(static_pref_list_group_h):
-        static_prefs_group_h[group] = [FIRST_LINE]
+        static_prefs_group_h[group] = [first_line]
         static_prefs_group_h[group].append(
             STATIC_PREFS_GROUP_H_TEMPLATE1.format(group=group)
         )
@@ -344,7 +346,7 @@ def generate_code(pref_list):
         )
 
     # static_prefs.rs contains the Rust macro getters.
-    static_prefs_rs = [FIRST_LINE, "", 'extern "C" {']
+    static_prefs_rs = [first_line, "", 'extern "C" {']
     static_prefs_rs.extend(static_prefs_rs_decls)
     static_prefs_rs.extend(["}", "", "#[macro_export]", "macro_rules! pref {"])
     static_prefs_rs.extend(static_prefs_rs_macro)
@@ -382,7 +384,8 @@ def emit_code(fd, pref_list_filename):
 
     try:
         pref_list = yaml.safe_load(pp.out.getvalue())
-        code = generate_code(pref_list)
+        input_file = os.path.relpath(pref_list_filename, os.environ["TOPSRCDIR"])
+        code = generate_code(pref_list, input_file)
     except (IOError, ValueError) as e:
         print("{}: error:\n  {}\n".format(pref_list_filename, e))
         sys.exit(1)