Re: [PATCH 3/3] for-each-ref: introduce %(upstream:track[short])

Introduce %(upstream:track) to display "[ahead M, behind N]" and
%(upstream:trackshort) to display "=", ">", "<", or "<>"
appropriately (inspired by contrib/completion/git-prompt.sh).

Now you can use the following format in for-each-ref:

 %C(green)%(refname:short)%C(reset)%(upstream:trackshort)

to display refs with terse tracking information.

Note that :track and :trackshort only work with "upstream", and error
out when used with anything else.

Signed-off-by: Ramkumar Ramachandra <redacted>
---
Documentation/git-for-each-ref.txt |  6 +++++-
builtin/for-each-ref.c             | 44 ++++++++++++++++++++++++++++++++++++--
2 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt
index f1d4e9e..682eaa8 100644
--- a/Documentation/git-for-each-ref.txt
+++ b/Documentation/git-for-each-ref.txt

@@ -93,7 +93,11 @@ objectname::

upstream::
 The name of a local ref which can be considered ``upstream''
 from the displayed ref. Respects `:short` in the same way as
- `refname` above.
+ `refname` above.  Additionally respects `:track` to show
+ "[ahead N, behind M]" and `:trackshort` to show the terse
+ version (like the prompt) ">", "<", "<>", or "=".  Has no
+ effect if the ref does not have tracking information
+ associated with it.

HEAD::
 Used to indicate the currently checked out branch.  Is '*' if

diff --git a/builtin/for-each-ref.c b/builtin/for-each-ref.c
index e54b5d8..10843bb 100644
--- a/builtin/for-each-ref.c
+++ b/builtin/for-each-ref.c

@@ -631,6 +631,7 @@ static void populate_value(struct refinfo *ref)
 int eaten, i;
 unsigned long size;
 const unsigned char *tagged;
+ int upstream_present = 0;

 ref->value = xcalloc(sizeof(struct atom_value), used_atom_cnt);

@@ -648,6 +649,7 @@ static void populate_value(struct refinfo *ref)
 int deref = 0;
 const char *refname;
 const char *formatp;
+ struct branch *branch;

 if (*name == '*') {
 deref = 1;

@@ -659,7 +661,6 @@ static void populate_value(struct refinfo *ref)
 else if (!prefixcmp(name, "symref"))
 refname = ref->symref ? ref->symref : "";
 else if (!prefixcmp(name, "upstream")) {
- struct branch *branch;
 /* only local branches may have an upstream */
 if (prefixcmp(ref->refname, "refs/heads/"))
 continue;

@@ -669,6 +670,7 @@ static void populate_value(struct refinfo *ref)
     !branch->merge[0]->dst)
 continue;
 refname = branch->merge[0]->dst;
+ upstream_present = 1;
 }
 else if (!strcmp(name, "flag")) {
 char buf[256], *cp = buf;

@@ -686,6 +688,7 @@ static void populate_value(struct refinfo *ref)
 } else if (!strcmp(name, "HEAD")) {
 const char *head;
 unsigned char sha1[20];
+
 head = resolve_ref_unsafe("HEAD", sha1, 1, NULL);
 if (!strcmp(ref->refname, head))
 v->s = "*";

@@ -698,11 +701,48 @@ static void populate_value(struct refinfo *ref)
 formatp = strchr(name, ':');
 /* look for "short" refname format */
 if (formatp) {
+ int num_ours, num_theirs;
+
 formatp++;
 if (!strcmp(formatp, "short"))
 refname = shorten_unambiguous_ref(refname,
       warn_ambiguous_refs);
- else
+ else if (!strcmp(formatp, "track") &&
+ !prefixcmp(name, "upstream")) {
+ char buf[40];
+
+ if (!upstream_present)
+ continue;
+ stat_tracking_info(branch, &num_ours, &num_theirs);
+ if (!num_ours && !num_theirs)
+ v->s = "";
+ else if (!num_ours) {
+ sprintf(buf, "[behind %d]", num_theirs);
+ v->s = xstrdup(buf);
+ } else if (!num_theirs) {
+ sprintf(buf, "[ahead %d]", num_ours);
+ v->s = xstrdup(buf);
+ } else {
+ sprintf(buf, "[ahead %d, behind %d]",
+ num_ours, num_theirs);
+ v->s = xstrdup(buf);
+ }
+ continue;
+ } else if (!strcmp(formatp, "trackshort") &&
+ !prefixcmp(name, "upstream")) {
+ if (!upstream_present)
+ continue;
+ stat_tracking_info(branch, &num_ours, &num_theirs);
+ if (!num_ours && !num_theirs)
+ v->s = "=";
+ else if (!num_ours)
+ v->s = "<";
+ else if (!num_theirs)
+ v->s = ">";
+ else
+ v->s = "<>";
+ continue;
+ } else
 die("unknown %.*s format %s",
     (int)(formatp - name), name, formatp);
 }

-- 
1.8.4.478.g55109e3

--