Improve parent blame to detect renames by using the previous information

From git commit 96e117099c0e4f7d508eb071f60b6275038f6f37:

 It gives the parent commit of the blamed commit, _and_ a path in that
 parent commit that corresponds to the blamed path --- in short, it is
 the origin that would have been blamed (or passed blame through) for
 the line _if_ the blamed commit did not change that line.

This functionality was released in git version 1.6.3 in 2009-05-06.

diff --git a/NEWS b/NEWS
index f46ee701454f992162952c10831d3db9ece1ce64..86bad0c251fa751ed02fcdd3156e9aa38d8417ac 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -39,6 +39,8 @@ Bug fixes:
  - Fix unbind to behave as if the keybinding was never defined.
  - Fix unbind to also cover built-in run requests.
  - Fix parsing of unknown keymap names.
+ - Blame view: fix parent blame to detect renames. It uses "previous"
+   line info from the blame porcelain output added in git version 1.6.3.
 
 tig-0.15
 --------

diff --git a/tig.c b/tig.c
index 810e5e785135ddbfb84b77c822ebb5ab3e7d6296..c2417bfee168eb4b52c6287ee01bcc524a9bc635 100644 (file)
--- a/tig.c
+++ b/tig.c
@@ -3977,73 +3977,6 @@ parse_author_line(char *ident, const char **author, struct time *time)
        }
 }
 
-static bool
-open_commit_parent_menu(char buf[SIZEOF_STR], int *parents)
-{
-       char rev[SIZEOF_REV];
-       const char *revlist_argv[] = {
-               "git", "log", "--no-color", "-1", "--pretty=format:%s", rev, NULL
-       };
-       struct menu_item *items;
-       char text[SIZEOF_STR];
-       bool ok = TRUE;
-       int i;
-
-       items = calloc(*parents + 1, sizeof(*items));
-       if (!items)
-               return FALSE;
-
-       for (i = 0; i < *parents; i++) {
-               string_copy_rev(rev, &buf[SIZEOF_REV * i]);
-               if (!io_run_buf(revlist_argv, text, sizeof(text)) ||
-                   !(items[i].text = strdup(text))) {
-                       ok = FALSE;
-                       break;
-               }
-       }
-
-       if (ok) {
-               *parents = 0;
-               ok = prompt_menu("Select parent", items, parents);
-       }
-       for (i = 0; items[i].text; i++)
-               free((char *) items[i].text);
-       free(items);
-       return ok;
-}
-
-static bool
-select_commit_parent(const char *id, char rev[SIZEOF_REV], const char *path)
-{
-       char buf[SIZEOF_STR * 4];
-       const char *revlist_argv[] = {
-               "git", "log", "--no-color", "-1",
-                       "--pretty=format:%P", id, "--", path, NULL
-       };
-       int parents;
-
-       if (!io_run_buf(revlist_argv, buf, sizeof(buf)) ||
-           (parents = strlen(buf) / 40) < 0) {
-               report("Failed to get parent information");
-               return FALSE;
-
-       } else if (parents == 0) {
-               if (path)
-                       report("Path '%s' does not exist in the parent", path);
-               else
-                       report("The selected commit has no parents");
-               return FALSE;
-       }
-
-       if (parents == 1)
-               parents = 0;
-       else if (!open_commit_parent_menu(buf, &parents))
-               return FALSE;
-
-       string_copy_rev(rev, &buf[41 * parents]);
-       return TRUE;
-}
-
 /*
  * Pager backend
  */
@@ -4898,7 +4831,8 @@ struct blame_commit {
        const char *author;             /* Author of the commit. */
        struct time time;               /* Date from the author ident. */
        char filename[128];             /* Name of file. */
-       bool has_previous;              /* Was a "previous" line detected. */
+       char parent_id[SIZEOF_REV];     /* Parent/previous SHA1 ID. */
+       char parent_filename[128];      /* Parent/previous name of file. */
 };
 
 struct blame {
@@ -5116,7 +5050,11 @@ blame_read(struct view *view, char *line)
                string_ncopy(commit->title, line, strlen(line));
 
        } else if (match_blame_header("previous ", &line)) {
-               commit->has_previous = TRUE;
+               if (strlen(line) <= SIZEOF_REV)
+                       return FALSE;
+               string_copy_rev(commit->parent_id, line);
+               line += SIZEOF_REV;
+               string_ncopy(commit->parent_filename, line, strlen(line));
 
        } else if (match_blame_header("filename ", &line)) {
                string_ncopy(commit->filename, line, strlen(line));
@@ -5223,10 +5161,13 @@ blame_request(struct view *view, enum request request, struct line *line)
                break;
 
        case REQ_PARENT:
-               if (check_blame_commit(blame, TRUE) &&
-                   select_commit_parent(blame->commit->id, opt_ref,
-                                        blame->commit->filename)) {
-                       string_copy(opt_file, blame->commit->filename);
+               if (!check_blame_commit(blame, TRUE))
+                       break;
+               if (!*blame->commit->parent_id) {
+                       report("The selected commit has no parents");
+               } else {
+                       string_copy_rev(opt_ref, blame->commit->parent_id);
+                       string_copy(opt_file, blame->commit->parent_filename);
                        setup_blame_parent_line(view, blame);
                        open_view(view, REQ_VIEW_BLAME, OPEN_REFRESH);
                }
@@ -5247,7 +5188,7 @@ blame_request(struct view *view, enum request request, struct line *line)
                                        "-C", "-M", "HEAD", "--", view->vid, NULL
                        };
 
-                       if (!blame->commit->has_previous) {
+                       if (!*blame->commit->parent_id) {
                                diff_index_argv[1] = "diff";
                                diff_index_argv[2] = "--no-color";
                                diff_index_argv[6] = "--";