ui-commit: handle root commits

Both cgit_print_diff() and cgit_diff_tree() handles root commits nicely,
but cgit_print_commit() forgot to check the case of 0 parents.

This fixes it, and adds tests to avoid future regressions.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

2 files changed, 22 insertions, 3 deletions

diff --git a/tests/t0105-commit.sh b/tests/t0105-commit.sh
index aa2bf33..4e1236b 100755
--- a/tests/t0105-commit.sh
+++ b/tests/t0105-commit.sh
@@ -6,17 +6,32 @@ prepare_tests "Check content on commit page"
 
 run_test 'generate foo/commit' 'cgit_url "foo/commit" >trash/tmp'
 run_test 'find tree link' 'grep -e "<a href=./foo/tree/.>" trash/tmp'
 run_test 'find parent link' 'grep -E "<a href=./foo/commit/\?id=.+>" trash/tmp'
 
 run_test 'find commit subject' '
         grep -e "<div class=.commit-subject.>commit 5</div>" trash/tmp
 '
 
 run_test 'find commit msg' 'grep -e "<div class=.commit-msg.></div>" trash/tmp'
 run_test 'find diffstat' 'grep -e "<table summary=.diffstat. class=.diffstat.>" trash/tmp'
 
 run_test 'find diff summary' '
          grep -e "1 files changed, 1 insertions, 0 deletions" trash/tmp
 '
 
+run_test 'get root commit' '
+         root=$(cd trash/repos/foo && git rev-list --reverse HEAD | head -1) &&
+         cgit_url "foo/commit&id=$root" >trash/tmp &&
+         grep "</html>" trash/tmp
+'
+
+run_test 'root commit contains diffstat' '
+         grep "<a href=./foo/diff/file-1.>file-1</a>" trash/tmp
+'
+
+run_test 'root commit contains diff' '
+         grep ">diff --git a/file-1 b/file-1<" trash/tmp &&
+         grep -e "<div class=.add.>+1</div>" trash/tmp
+'
+
 tests_done
diff --git a/ui-commit.c b/ui-commit.c
index 1aa5d34..4bbb391 100644
--- a/ui-commit.c
+++ b/ui-commit.c
@@ -5,32 +5,33 @@
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 #include "html.h"
 #include "ui-shared.h"
 #include "ui-diff.h"
 
 void cgit_print_commit(char *hex)
 {
         struct commit *commit, *parent;
         struct commitinfo *info;
         struct commit_list *p;
         unsigned char sha1[20];
         char *tmp;
+        int parents = 0;
 
         if (!hex)
                 hex = ctx.qry.head;
 
         if (get_sha1(hex, sha1)) {
                 cgit_print_error(fmt("Bad object id: %s", hex));
                 return;
         }
         commit = lookup_commit_reference(sha1);
         if (!commit) {
                 cgit_print_error(fmt("Bad commit reference: %s", hex));
                 return;
         }
         info = cgit_parse_commit(commit);
 
         html("<table summary='commit info' class='commit-info'>\n");
@@ -62,37 +63,40 @@ void cgit_print_commit(char *hex)
               for (p = commit->parents; p ; p = p->next) {
                 parent = lookup_commit_reference(p->item->object.sha1);
                 if (!parent) {
                         html("<tr><td colspan='3'>");
                         cgit_print_error("Error reading parent commit");
                         html("</td></tr>");
                         continue;
                 }
                 html("<tr><th>parent</th>"
                      "<td colspan='2' class='sha1'>");
                 cgit_commit_link(sha1_to_hex(p->item->object.sha1), NULL, NULL,
                                  ctx.qry.head, sha1_to_hex(p->item->object.sha1));
                 html(" (");
                 cgit_diff_link("diff", NULL, NULL, ctx.qry.head, hex,
                                sha1_to_hex(p->item->object.sha1), NULL);
                 html(")</td></tr>");
+                parents++;
         }
         if (ctx.repo->snapshots) {
                 html("<tr><th>download</th><td colspan='2' class='sha1'>");
                 cgit_print_snapshot_links(ctx.qry.repo, ctx.qry.head,
                                           hex, ctx.repo->snapshots);
                 html("</td></tr>");
         }
         html("</table>\n");
         html("<div class='commit-subject'>");
         html_txt(info->subject);
         html("</div>");
         html("<div class='commit-msg'>");
         html_txt(info->msg);
         html("</div>");
-        if (!(commit->parents && commit->parents->next &&
-              commit->parents->next->next)) {
-                tmp = sha1_to_hex(commit->parents->item->object.sha1);
+        if (parents < 3) {
+                if (parents)
+                        tmp = sha1_to_hex(commit->parents->item->object.sha1);
+                else
+                        tmp = NULL;
                 cgit_print_diff(ctx.qry.sha1, tmp, NULL);
         }
         cgit_free_commitinfo(info);
 }