[PATCH v2 8/8] grep: -W: don't extend context to trailing empty lines
- From
René Scharfe <l.s.r@web.de>
- Date
- May 28, 2016, 15:06 UTC
- Message-ID
- <5749B3EB.7090308@web.de>
- In-Reply-To
- <5749AF59.2070704@web.de>
Empty lines between functions are shown by grep -W, as it considers them to be part of the function preceding them. They are not interesting in most languages. The previous patches stopped showing them for diff -W.
Stop showing empty lines trailing a function with grep -W. Grep scans the lines of a buffer from top to bottom and prints matching lines immediately. Thus we need to peek ahead in order to determine if an empty line is part of a function body and worth showing or not.
Remember how far ahead we peeked in order to avoid having to do so repeatedly when handling multiple consecutive empty lines.
Signed-off-by: Rene Scharfe <l.s.r@web.de> --- grep.c | 28 ++++++++++++++++++++++++++-- t/t7810-grep.sh | 2 +- 2 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/grep.c b/grep.c index ec6f7ff..1e15b62 100644 --- a/grep.c +++ b/grep.c @@ -1396,9 +1396,17 @@ static int fill_textconv_grep(struct userdiff_driver *driver, return 0; } +static int is_empty_line(const char *bol, const char *eol) +{ + while (bol < eol && isspace(*bol)) + bol++; + return bol == eol; +} + static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int collect_hits) { char *bol; + char *peek_bol = NULL; unsigned long left; unsigned lno = 1; unsigned last_hit = 0; @@ -1543,8 +1551,24 @@ static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int colle show_function = 1; goto next_line; } - if (show_function && match_funcname(opt, gs, bol, eol)) - show_function = 0; + if (show_function && (!peek_bol || peek_bol < bol)) { + unsigned long peek_left = left; + char *peek_eol = eol; + + /* + * Trailing empty lines are not interesting. + * Peek past them to see if they belong to the + * body of the current function. + */ + peek_bol = bol; + while (is_empty_line(peek_bol, peek_eol)) { + peek_bol = peek_eol + 1; + peek_eol = end_of_line(peek_bol, &peek_left); + } + + if (match_funcname(opt, gs, peek_bol, peek_eol)) + show_function = 0; + } if (show_function || (last_hit && lno <= last_hit + opt->post_context)) { /* If the last hit is within the post context, diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh index 26912dc..960425a 100755 --- a/t/t7810-grep.sh +++ b/t/t7810-grep.sh @@ -748,7 +748,7 @@ hello.c-#include <assert.h> hello.c:#include <stdio.h> EOF -test_expect_failure 'grep -W shows no trailing empty lines' ' +test_expect_success 'grep -W shows no trailing empty lines' ' git grep -W stdio >actual && test_cmp expected actual '
-- 2.8.3