[llvm] 12c2646 - [gn build] sync script: only compute tokloc when adding files

[Nico Weber via llvm-commits]

Author: Nico Weber
Date: 2020-11-25T21:05:13-05:00
New Revision: 12c2646feb10c3aa14f590bcf9f5a3f9fc7b41b7

URL: https://github.com/llvm/llvm-project/commit/12c2646feb10c3aa14f590bcf9f5a3f9fc7b41b7
DIFF: https://github.com/llvm/llvm-project/commit/12c2646feb10c3aa14f590bcf9f5a3f9fc7b41b7.diff

LOG: [gn build] sync script: only compute tokloc when adding files

No behavior change, but maybe a bit clearer.

Added: 
    

Modified: 
    llvm/utils/gn/build/sync_source_lists_from_cmake.py

Removed: 
    


################################################################################
diff  --git a/llvm/utils/gn/build/sync_source_lists_from_cmake.py b/llvm/utils/gn/build/sync_source_lists_from_cmake.py
index bb57d49179ea..5c96fd7263f4 100755
--- a/llvm/utils/gn/build/sync_source_lists_from_cmake.py
+++ b/llvm/utils/gn/build/sync_source_lists_from_cmake.py
@@ -26,20 +26,17 @@
 def patch_gn_file(gn_file, add, remove):
     with open(gn_file) as f:
         gn_contents = f.read()
-
-    srcs_tok = 'sources = ['
-    tokloc = gn_contents.find(srcs_tok)
-    while tokloc != -1 and tokloc + len(srcs_tok) < len(gn_contents) and \
-            gn_contents[tokloc + len(srcs_tok)] == ']':
-        tokloc = gn_contents.find(srcs_tok, tokloc + 1)
-
-    if tokloc == -1: raise ValueError(gn_file + ': Failed to find source list')
     if add:
+        srcs_tok = 'sources = ['
+        tokloc = gn_contents.find(srcs_tok)
+        while tokloc != -1 and tokloc + len(srcs_tok) < len(gn_contents) and \
+                gn_contents[tokloc + len(srcs_tok)] == ']':
+            tokloc = gn_contents.find(srcs_tok, tokloc + 1)
+        if tokloc == -1: raise ValueError(gn_file + ': No source list')
         if gn_contents.find(srcs_tok, tokloc + 1) != -1:
             raise ValueError(gn_file + ': Multiple source lists')
         if gn_contents.find('# NOSORT', 0, tokloc) != -1:
             raise ValueError(gn_file + ': Found # NOSORT, needs manual merge')
-
         tokloc += len(srcs_tok)
         for a in add:
             gn_contents = (gn_contents[:tokloc] + ('"%s",' % a) +