From 19210d5715a8504debf0f479791c0f0d1aba91bf Mon Sep 17 00:00:00 2001
From: Peter Dillinger <peterd@fb.com>
Date: Wed, 27 Jan 2021 16:19:43 -0800
Subject: [PATCH] Accurate re-generate command in TARGETS file (#7902)

Summary:
TIL we have different versions of TARGETS file generated with
options passed to buckifier. Someone thought they were totally fine to
squash the file by re-running the command to generate (pretty reasonable
assumption) but the command was incorrect due to missing the extra
argument used to generate THAT TARGETS file.

This change includes in the command written in the TARGETS header the
extra argument passed to buckify (when used).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7902

Test Plan:
manual, as in the (now fixed) comments at the top of
buckify_rocksdb.py

Reviewed By: ajkr

Differential Revision: D26108317

Pulled By: pdillinger

fbshipit-source-id: 46e93dc1465e27bd18e0e0baa8eeee1b591c765d
---
 TARGETS                      |  3 ++-
 buckifier/buckify_rocksdb.py | 16 +++++++++++-----
 buckifier/targets_builder.py |  5 +++--
 buckifier/targets_cfg.py     |  7 ++++---
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/TARGETS b/TARGETS
index 4b9460f05f..26c6d9a48c 100644
--- a/TARGETS
+++ b/TARGETS
@@ -1,4 +1,5 @@
-# This file @generated by `python3 buckifier/buckify_rocksdb.py`
+# This file @generated by:
+#$ python3 buckifier/buckify_rocksdb.py
 # --> DO NOT EDIT MANUALLY <--
 # This file is a Facebook-specific integration for buck builds, so can
 # only be validated by Facebook employees.
diff --git a/buckifier/buckify_rocksdb.py b/buckifier/buckify_rocksdb.py
index f0909bc617..6dfedbce1e 100644
--- a/buckifier/buckify_rocksdb.py
+++ b/buckifier/buckify_rocksdb.py
@@ -24,10 +24,10 @@ from util import ColorString
 # (This generates a TARGET file without user-specified dependency for unit
 # tests.)
 # $python3 buckifier/buckify_rocksdb.py \
-#        '{"fake": { \
-#                      "extra_deps": [":test_dep", "//fakes/module:mock1"],  \
-#                      "extra_compiler_flags": ["-DROCKSDB_LITE", "-Os"], \
-#                  } \
+#        '{"fake": {
+#                      "extra_deps": [":test_dep", "//fakes/module:mock1"],
+#                      "extra_compiler_flags": ["-DROCKSDB_LITE", "-Os"]
+#                  }
 #         }'
 # (Generated TARGETS file has test_dep and mock1 as dependencies for RocksDB
 # unit tests, and will use the extra_compiler_flags to compile the unit test
@@ -129,7 +129,13 @@ def generate_targets(repo_path, deps_map):
     if src_mk is None or cc_files is None or parallel_tests is None:
         return False
 
-    TARGETS = TARGETSBuilder("%s/TARGETS" % repo_path)
+    extra_argv = ""
+    if len(sys.argv) >= 2:
+        # Heuristically quote and canonicalize whitespace for inclusion
+        # in how the file was generated.
+        extra_argv = " '{0}'".format(" ".join(sys.argv[1].split()))
+
+    TARGETS = TARGETSBuilder("%s/TARGETS" % repo_path, extra_argv)
 
     # rocksdb_lib
     TARGETS.add_library(
diff --git a/buckifier/targets_builder.py b/buckifier/targets_builder.py
index e55238b2fa..bf61b3ae1f 100644
--- a/buckifier/targets_builder.py
+++ b/buckifier/targets_builder.py
@@ -25,10 +25,11 @@ def pretty_list(lst, indent=8):
 
 
 class TARGETSBuilder(object):
-    def __init__(self, path):
+    def __init__(self, path, extra_argv):
         self.path = path
         self.targets_file = open(path, 'wb')
-        header = targets_cfg.rocksdb_target_header_template
+        header = targets_cfg.rocksdb_target_header_template.format(
+            extra_argv=extra_argv)
         self.targets_file.write(header.encode("utf-8"))
         self.total_lib = 0
         self.total_bin = 0
diff --git a/buckifier/targets_cfg.py b/buckifier/targets_cfg.py
index 0c20ef095c..986a75b881 100644
--- a/buckifier/targets_cfg.py
+++ b/buckifier/targets_cfg.py
@@ -5,7 +5,8 @@ from __future__ import print_function
 from __future__ import unicode_literals
 
 rocksdb_target_header_template = \
-    """# This file \100generated by `python3 buckifier/buckify_rocksdb.py`
+    """# This file \100generated by:
+#$ python3 buckifier/buckify_rocksdb.py{extra_argv}
 # --> DO NOT EDIT MANUALLY <--
 # This file is a Facebook-specific integration for buck builds, so can
 # only be validated by Facebook employees.
@@ -99,11 +100,11 @@ ROCKSDB_PREPROCESSOR_FLAGS = [
     "-I" + REPO_PATH,
 ]
 
-ROCKSDB_ARCH_PREPROCESSOR_FLAGS = {
+ROCKSDB_ARCH_PREPROCESSOR_FLAGS = {{
     "x86_64": [
         "-DHAVE_PCLMUL",
     ],
-}
+}}
 
 build_mode = read_config("fbcode", "build_mode")