From 5a7e39c0cbca3f2b94834167154472a61fc34a03 Mon Sep 17 00:00:00 2001 From: Sebastian Hahn Date: Mon, 17 Apr 2017 10:07:31 +0200 Subject: [PATCH] Fix diff generation with line added at start The consdiff generation logic would skip over lines added at the start of the second file, and generate a diff that it would the immediately refuse because it couldn't be used to reproduce the second file from the first. Fixes #21996. --- src/or/consdiff.c | 2 +- src/test/test_consdiff.c | 11 +++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/src/or/consdiff.c b/src/or/consdiff.c index d2a2af1b5f..cd22fd44a1 100644 --- a/src/or/consdiff.c +++ b/src/or/consdiff.c @@ -671,7 +671,7 @@ gen_ed_diff(const smartlist_t *cons1, const smartlist_t *cons2, */ i1=len1-1, i2=len2-1; char buf[128]; - while (i1 > 0 || i2 > 0) { + while (i1 >= 0 || i2 >= 0) { int start1x, start2x, end1, end2, added, deleted; diff --git a/src/test/test_consdiff.c b/src/test/test_consdiff.c index 1b4e2ad3c1..193d524c81 100644 --- a/src/test/test_consdiff.c +++ b/src/test/test_consdiff.c @@ -622,6 +622,17 @@ test_consdiff_gen_ed_diff(void *arg) tt_str_eq_line(".", smartlist_get(diff, 5)); tt_str_eq_line("2d", smartlist_get(diff, 6)); + smartlist_clear(cons1); + smartlist_clear(cons2); + consensus_split_lines(cons1, "B\n", area); + consensus_split_lines(cons2, "A\nB\n", area); + diff = gen_ed_diff(cons1, cons2, area); + tt_ptr_op(NULL, OP_NE, diff); + tt_int_op(3, OP_EQ, smartlist_len(diff)); + tt_str_eq_line("0a", smartlist_get(diff, 0)); + tt_str_eq_line("A", smartlist_get(diff, 1)); + tt_str_eq_line(".", smartlist_get(diff, 2)); + /* TODO: small real use-cases, i.e. consensuses. */ done: