revision: --skip=<n>

This adds --skip=<n> option to revision traversal machinery.
Documentation and test were added by Robert Fitzsimons.

Signed-off-by: Robert Fitzsimons <robfitz@273k.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Documentation/git-rev-list.txt b/Documentation/git-rev-list.txt
index ec43c0b3a8ca87c2bd0116e1a20061eda3ca3f21..9e0dcf8d3fef2495da4940ce662a46cc8a2bf621 100644 (file)
--- a/Documentation/git-rev-list.txt
+++ b/Documentation/git-rev-list.txt
@@ -10,6 +10,7 @@ SYNOPSIS
 --------
 [verse]
 'git-rev-list' [ \--max-count=number ]
+            [ \--skip=number ]
             [ \--max-age=timestamp ]
             [ \--min-age=timestamp ]
             [ \--sparse ]
@@ -139,6 +140,10 @@ limiting may be applied.
 
        Limit the number of commits output.
 
+--skip='number'::
+
+       Skip 'number' commits before starting to show the commit output.
+
 --since='date', --after='date'::
 
        Show commits more recent than a specific date.

diff --git a/revision.c b/revision.c
index 7b6f91f83ef4a04f1af74daf37fbae2da7eac0d7..5dc1e70260d45efded8f2329b6a4d8bf050c0537 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -523,6 +523,7 @@ void init_revisions(struct rev_info *revs, const char *prefix)
        revs->prefix = prefix;
        revs->max_age = -1;
        revs->min_age = -1;
+       revs->skip_count = -1;
        revs->max_count = -1;
 
        revs->prune_fn = NULL;
@@ -759,6 +760,10 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
                                revs->max_count = atoi(arg + 12);
                                continue;
                        }
+                       if (!strncmp(arg, "--skip=", 7)) {
+                               revs->skip_count = atoi(arg + 7);
+                               continue;
+                       }
                        /* accept -<digit>, like traditional "head" */
                        if ((*arg == '-') && isdigit(arg[1])) {
                                revs->max_count = atoi(arg + 1);
@@ -1122,23 +1127,11 @@ static int commit_match(struct commit *commit, struct rev_info *opt)
                           commit->buffer, strlen(commit->buffer));
 }
 
-struct commit *get_revision(struct rev_info *revs)
+static struct commit *get_revision_1(struct rev_info *revs)
 {
-       struct commit_list *list = revs->commits;
-
-       if (!list)
+       if (!revs->commits)
                return NULL;
 
-       /* Check the max_count ... */
-       switch (revs->max_count) {
-       case -1:
-               break;
-       case 0:
-               return NULL;
-       default:
-               revs->max_count--;
-       }
-
        do {
                struct commit_list *entry = revs->commits;
                struct commit *commit = entry->item;
@@ -1205,3 +1198,28 @@ struct commit *get_revision(struct rev_info *revs)
        } while (revs->commits);
        return NULL;
 }
+
+struct commit *get_revision(struct rev_info *revs)
+{
+       struct commit *c = NULL;
+
+       if (0 < revs->skip_count) {
+               while ((c = get_revision_1(revs)) != NULL) {
+                       if (revs->skip_count-- <= 0)
+                               break;
+               }
+       }
+
+       /* Check the max_count ... */
+       switch (revs->max_count) {
+       case -1:
+               break;
+       case 0:
+               return NULL;
+       default:
+               revs->max_count--;
+       }
+       if (c)
+               return c;
+       return get_revision_1(revs);
+}

diff --git a/revision.h b/revision.h
index 3adab9590a14e25c2659a1933db4af456c263a5b..81f522c35d21397f432bdeed42dab1f0044df377 100644 (file)
--- a/revision.h
+++ b/revision.h
@@ -75,6 +75,7 @@ struct rev_info {
        struct grep_opt *grep_filter;
 
        /* special limits */
+       int skip_count;
        int max_count;
        unsigned long max_age;
        unsigned long min_age;

diff --git a/t/t6005-rev-list-count.sh b/t/t6005-rev-list-count.sh
new file mode 100755 (executable)
index 0000000..334fccf
--- /dev/null
+++ b/t/t6005-rev-list-count.sh
@@ -0,0 +1,51 @@
+#!/bin/sh
+
+test_description='git-rev-list --max-count and --skip test'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+    for n in 1 2 3 4 5 ; do \
+        echo $n > a ; \
+        git add a ; \
+        git commit -m "$n" ; \
+    done
+'
+
+test_expect_success 'no options' '
+    test $(git-rev-list HEAD | wc -l) = 5
+'
+
+test_expect_success '--max-count' '
+    test $(git-rev-list HEAD --max-count=0 | wc -l) = 0 &&
+    test $(git-rev-list HEAD --max-count=3 | wc -l) = 3 &&
+    test $(git-rev-list HEAD --max-count=5 | wc -l) = 5 &&
+    test $(git-rev-list HEAD --max-count=10 | wc -l) = 5
+'
+
+test_expect_success '--max-count all forms' '
+    test $(git-rev-list HEAD --max-count=1 | wc -l) = 1 &&
+    test $(git-rev-list HEAD -1 | wc -l) = 1 &&
+    test $(git-rev-list HEAD -n1 | wc -l) = 1 &&
+    test $(git-rev-list HEAD -n 1 | wc -l) = 1
+'
+
+test_expect_success '--skip' '
+    test $(git-rev-list HEAD --skip=0 | wc -l) = 5 &&
+    test $(git-rev-list HEAD --skip=3 | wc -l) = 2 &&
+    test $(git-rev-list HEAD --skip=5 | wc -l) = 0 &&
+    test $(git-rev-list HEAD --skip=10 | wc -l) = 0
+'
+
+test_expect_success '--skip --max-count' '
+    test $(git-rev-list HEAD --skip=0 --max-count=0 | wc -l) = 0 &&
+    test $(git-rev-list HEAD --skip=0 --max-count=10 | wc -l) = 5 &&
+    test $(git-rev-list HEAD --skip=3 --max-count=0 | wc -l) = 0 &&
+    test $(git-rev-list HEAD --skip=3 --max-count=1 | wc -l) = 1 &&
+    test $(git-rev-list HEAD --skip=3 --max-count=2 | wc -l) = 2 &&
+    test $(git-rev-list HEAD --skip=3 --max-count=10 | wc -l) = 2 &&
+    test $(git-rev-list HEAD --skip=5 --max-count=10 | wc -l) = 0 &&
+    test $(git-rev-list HEAD --skip=10 --max-count=10 | wc -l) = 0
+'
+
+test_done