[PATCH/RFC v1 1/1] bug fix, diff whitespace ignore options
- From
Keith Cascio <keith@cs.ucla.edu>
- Date
- Jan 19, 2009, 02:01 UTC
- Message-ID
- <alpine.GSO.2.00.0901181754190.9333@kiwi.cs.ucla.edu>
- In-Reply-To
- <alpine.DEB.1.00.0901190218470.3586@pacific.mpi-cbg.de>
Fixed bug in diff whitespace ignore options. It is now OK to specify more than one whitespace ignore option on the command line. In unit test 4015, expect success rather than failure for 4 cases. Note: I do not fully understand why this fix works, but it passes all 68 t4???-* diff test scripts.
The semantics of the three whitespace ignore flags { -w, -b, --ignore-space-at-eol } obey a relation of transitive implication, i.e. the stronger options imply the weaker options: -w implies the other two -b implies --ignore-space-at-eol --ignore-space-at-eol implies only itself
Therefore it is never necessary to specify more than one of these on the command line. Yet we imagine scenarios where software wrappers (e.g. GUIs, etc) generate command lines that switch on more than one of these flags simultaneously. It is unreasonable to prohibit specifying more than one, since a new user might not immediately discern the implication relation. Now we call such a command line valid and legal.
Signed-off-by: Keith Cascio <keith@cs.ucla.edu> --- t/t4015-diff-whitespace.sh | 8 ++++---- xdiff/xutils.c | 22 ++++++++++++---------- 2 files changed, 16 insertions(+), 14 deletions(-)
diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh index dbb608c..6d13da3 100755 --- a/t/t4015-diff-whitespace.sh +++ b/t/t4015-diff-whitespace.sh @@ -99,11 +99,11 @@ EOF git diff -w > out test_expect_success 'another test, with -w' 'test_cmp expect out' git diff -w -b > out -test_expect_failure 'another test, with -w -b' 'test_cmp expect out' +test_expect_success 'another test, with -w -b' 'test_cmp expect out' git diff -w --ignore-space-at-eol > out -test_expect_failure 'another test, with -w --ignore-space-at-eol' 'test_cmp expect out' +test_expect_success 'another test, with -w --ignore-space-at-eol' 'test_cmp expect out' git diff -w -b --ignore-space-at-eol > out -test_expect_failure 'another test, with -w -b --ignore-space-at-eol' 'test_cmp expect out' +test_expect_success 'another test, with -w -b --ignore-space-at-eol' 'test_cmp expect out' tr 'Q' '\015' << EOF > expect diff --git a/x b/x @@ -123,7 +123,7 @@ EOF git diff -b > out test_expect_success 'another test, with -b' 'test_cmp expect out' git diff -b --ignore-space-at-eol > out -test_expect_failure 'another test, with -b --ignore-space-at-eol' 'test_cmp expect out' +test_expect_success 'another test, with -b --ignore-space-at-eol' 'test_cmp expect out' tr 'Q' '\015' << EOF > expect diff --git a/x b/x diff --git a/xdiff/xutils.c b/xdiff/xutils.c index d7974d1..b9bda86 100644 --- a/xdiff/xutils.c +++ b/xdiff/xutils.c @@ -245,17 +245,19 @@ static unsigned long xdl_hash_record_with_whitespace(char const **data, while (ptr + 1 < top && isspace(ptr[1]) && ptr[1] != '\n') ptr++; - if (flags & XDF_IGNORE_WHITESPACE_CHANGE - && ptr[1] != '\n') { - ha += (ha << 5); - ha ^= (unsigned long) ' '; - } - if (flags & XDF_IGNORE_WHITESPACE_AT_EOL - && ptr[1] != '\n') { - while (ptr2 != ptr + 1) { + if( ! ( flags & XDF_IGNORE_WHITESPACE )){ + if( flags & XDF_IGNORE_WHITESPACE_CHANGE + && ptr[1] != '\n') { ha += (ha << 5); - ha ^= (unsigned long) *ptr2; - ptr2++; + ha ^= (unsigned long) ' '; + } + else if( flags & XDF_IGNORE_WHITESPACE_AT_EOL + && ptr[1] != '\n') { + while (ptr2 != ptr + 1) { + ha += (ha << 5); + ha ^= (unsigned long) *ptr2; + ptr2++; + } } } continue;
-- 1.6.1.203.ga83c8.dirty