From 68437ede53dccd1dea9e44e831a59de274d389de Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Carlos=20L=C3=B3pez?= <00xc@protonmail.com> Date: Wed, 22 Jun 2022 19:47:32 +0000 Subject: [PATCH] grep: add --max-count command line option MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds a command line option analogous to that of GNU grep(1)'s -m / --max-count, which users might already be used to. This makes it possible to limit the amount of matches shown in the output while keeping the functionality of other options such as -C (show code context) or -p (show containing function), which would be difficult to do with a shell pipeline (e.g. head(1)). Signed-off-by: Carlos López 00xc@protonmail.com Signed-off-by: Junio C Hamano --- Documentation/git-grep.txt | 9 ++++ builtin/grep.c | 9 ++++ grep.c | 2 +- grep.h | 2 + t/t7810-grep.sh | 87 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 108 insertions(+), 1 deletion(-) diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt index 3d393fbac1..58d944bd57 100644 --- a/Documentation/git-grep.txt +++ b/Documentation/git-grep.txt @@ -23,6 +23,7 @@ SYNOPSIS [--break] [--heading] [-p | --show-function] [-A ] [-B ] [-C ] [-W | --function-context] + [(-m | --max-count) ] [--threads ] [-f ] [-e] [--and|--or|--not|(|)|-e ...] @@ -238,6 +239,14 @@ providing this option will cause it to die. `git diff` works out patch hunk headers (see 'Defining a custom hunk-header' in linkgit:gitattributes[5]). +-m :: +--max-count :: + Limit the amount of matches per file. When using the `-v` or + `--invert-match` option, the search stops after the specified + number of non-matches. A value of -1 will return unlimited + results (the default). A value of 0 will exit immediately with + a non-zero status. + --threads :: Number of grep worker threads to use. See `grep.threads` in 'CONFIGURATION' for more information. diff --git a/builtin/grep.c b/builtin/grep.c index bcb07ea7f7..e6bcdf860c 100644 --- a/builtin/grep.c +++ b/builtin/grep.c @@ -961,6 +961,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix) OPT_BOOL_F(0, "ext-grep", &external_grep_allowed__ignored, N_("allow calling of grep(1) (ignored by this build)"), PARSE_OPT_NOCOMPLETE), + OPT_INTEGER('m', "max-count", &opt.max_count, + N_("maximum number of results per file")), OPT_END() }; grep_prefix = prefix; @@ -1101,6 +1103,13 @@ int cmd_grep(int argc, const char **argv, const char *prefix) if (recurse_submodules && untracked) die(_("--untracked not supported with --recurse-submodules")); + /* + * Optimize out the case where the amount of matches is limited to zero. + * We do this to keep results consistent with GNU grep(1). + */ + if (opt.max_count == 0) + return 1; + if (show_in_pager) { if (num_threads > 1) warning(_("invalid option combination, ignoring --threads")); diff --git a/grep.c b/grep.c index 82eb7da102..52a894c989 100644 --- a/grep.c +++ b/grep.c @@ -1615,7 +1615,7 @@ static int grep_source_1(struct grep_opt *opt, struct grep_source *gs, int colle return 0; goto next_line; } - if (hit) { + if (hit && (opt->max_count < 0 || count < opt->max_count)) { count++; if (opt->status_only) return 1; diff --git a/grep.h b/grep.h index c722d25ed9..bdcadce61b 100644 --- a/grep.h +++ b/grep.h @@ -171,6 +171,7 @@ struct grep_opt { int show_hunk_mark; int file_break; int heading; + int max_count; void *priv; void (*output)(struct grep_opt *opt, const void *data, size_t size); @@ -181,6 +182,7 @@ struct grep_opt { .relative = 1, \ .pathname = 1, \ .max_depth = -1, \ + .max_count = -1, \ .pattern_type_option = GREP_PATTERN_TYPE_UNSPECIFIED, \ .colors = { \ [GREP_COLOR_CONTEXT] = "", \ diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh index 6935601171..0f937990a0 100755 --- a/t/t7810-grep.sh +++ b/t/t7810-grep.sh @@ -77,6 +77,7 @@ test_expect_success setup ' # Say hello. function hello() { echo "Hello world." + echo "Hello again." } # hello # Still a no-op. @@ -595,6 +596,92 @@ test_expect_success 'grep --files-without-match --quiet' ' test_must_be_empty actual ' +test_expect_success 'grep --max-count 0 (must exit with non-zero)' ' + test_must_fail git grep --max-count 0 foo >actual && + test_must_be_empty actual +' + +test_expect_success 'grep --max-count 3' ' + cat >expected <<-EOF && + file:foo mmap bar + file:foo_mmap bar + file:foo_mmap bar mmap + EOF + git grep --max-count 3 foo >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count -1 (no limit)' ' + cat >expected <<-EOF && + file:foo mmap bar + file:foo_mmap bar + file:foo_mmap bar mmap + file:foo mmap bar_mmap + file:foo_mmap bar mmap baz + EOF + git grep --max-count -1 foo >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 1 --context 2' ' + cat >expected <<-EOF && + file-foo mmap bar + file:foo_mmap bar + file-foo_mmap bar mmap + EOF + git grep --max-count 1 --context 1 foo_mmap >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 1 --show-function' ' + cat >expected <<-EOF && + hello.ps1=function hello() { + hello.ps1: echo "Hello world." + EOF + git grep --max-count 1 --show-function Hello hello.ps1 >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 2 --show-function' ' + cat >expected <<-EOF && + hello.ps1=function hello() { + hello.ps1: echo "Hello world." + hello.ps1: echo "Hello again." + EOF + git grep --max-count 2 --show-function Hello hello.ps1 >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 1 --count' ' + cat >expected <<-EOF && + hello.ps1:1 + EOF + git grep --max-count 1 --count Hello hello.ps1 >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 1 (multiple files)' ' + cat >expected <<-EOF && + hello.c:#include + hello.ps1:# No-op. + EOF + git grep --max-count 1 -e o -- hello.\* >actual && + test_cmp expected actual +' + +test_expect_success 'grep --max-count 1 --context 1 (multiple files)' ' + cat >expected <<-EOF && + hello.c-#include + hello.c:#include + hello.c- + -- + hello.ps1:# No-op. + hello.ps1-function dummy() {} + EOF + git grep --max-count 1 --context 1 -e o -- hello.\* >actual && + test_cmp expected actual +' + cat >expected <