Maintain header order in merge_csv
Previously, if the --header property was not specified then merge_csv
would use a header constructed by sorting all the fields in the input
files. That required that any use of merge_csv which did not already
have headers in the required order would have to explicitly specify the
headers. That made it harder to use merge_csv as a generic tool as each
invocation needed to be aware of what headers were exported in the
output.
This change causes merge_csv to simply use the headers in the order in
which they are encountered in the input files. That removes the need to
specify the --header option when generating the index files.
Bug: 179354495
Test: m out/soong/hiddenapi/hiddenapi-index.csv out/soong/hiddenapi/hiddenapi-unsupported.csv
- make sure that they are not changed by this change.
Change-Id: I420b7d07aea85af6372cd7580a8be5e2cc82a513
diff --git a/scripts/hiddenapi/merge_csv.py b/scripts/hiddenapi/merge_csv.py
index b047aab..a65326c 100755
--- a/scripts/hiddenapi/merge_csv.py
+++ b/scripts/hiddenapi/merge_csv.py
@@ -55,14 +55,15 @@
if entry.endswith('.uau'):
csv_readers.append(dict_reader(io.TextIOWrapper(zip.open(entry, 'r'))))
-headers = set()
if args.header:
fieldnames = args.header.split(',')
else:
+ headers = {}
# Build union of all columns from source files:
for reader in csv_readers:
- headers = headers.union(reader.fieldnames)
- fieldnames = sorted(headers)
+ for fieldname in reader.fieldnames:
+ headers[fieldname] = ""
+ fieldnames = list(headers.keys())
# By default chain the csv readers together so that the resulting output is
# the concatenation of the rows from each of them: