Merge branch 'nd/fetch-ref-summary'

Improve the look of the way "git fetch" reports what happened to
each ref that was fetched.

* nd/fetch-ref-summary:
  fetch: reduce duplicate in ref update status lines with placeholder
  fetch: align all "remote -> local" output
  fetch: change flag code for displaying tag update and deleted ref
  fetch: refactor ref update status formatting code
  git-fetch.txt: document fetch output

4 files changed, 243 insertions, 40 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 226c12a154..e455faeb23 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -1243,6 +1243,11 @@ fetch.prune::
 	If true, fetch will automatically behave as if the `--prune`
 	option was given on the command line.  See also `remote.<name>.prune`.
 
+fetch.output::
+	Control how ref update status is printed. Valid values are
+	`full` and `compact`. Default value is `full`. See section
+	OUTPUT in linkgit:git-fetch[1] for detail.
+
 format.attach::
 	Enable multipart/mixed attachments as the default for
 	'format-patch'.  The value can also be a double quoted string
diff --git a/Documentation/git-fetch.txt b/Documentation/git-fetch.txt
index efe56e0808..9e4216999d 100644
--- a/Documentation/git-fetch.txt
+++ b/Documentation/git-fetch.txt
@@ -99,6 +99,57 @@ The latter use of the `remote.<repository>.fetch` values can be
 overridden by giving the `--refmap=<refspec>` parameter(s) on the
 command line.
 
+OUTPUT
+------
+
+The output of "git fetch" depends on the transport method used; this
+section describes the output when fetching over the Git protocol
+(either locally or via ssh) and Smart HTTP protocol.
+
+The status of the fetch is output in tabular form, with each line
+representing the status of a single ref. Each line is of the form:
+
+-------------------------------
+ <flag> <summary> <from> -> <to> [<reason>]
+-------------------------------
+
+The status of up-to-date refs is shown only if the --verbose option is
+used.
+
+In compact output mode, specified with configuration variable
+fetch.output, if either entire `<from>` or `<to>` is found in the
+other string, it will be substituted with `*` in the other string. For
+example, `master -> origin/master` becomes `master -> origin/*`.
+
+flag::
+	A single character indicating the status of the ref:
+(space);; for a successfully fetched fast-forward;
+`+`;; for a successful forced update;
+`-`;; for a successfully pruned ref;
+`t`;; for a successful tag update;
+`*`;; for a successfully fetched new ref;
+`!`;; for a ref that was rejected or failed to update; and
+`=`;; for a ref that was up to date and did not need fetching.
+
+summary::
+	For a successfully fetched ref, the summary shows the old and new
+	values of the ref in a form suitable for using as an argument to
+	`git log` (this is `<old>..<new>` in most cases, and
+	`<old>...<new>` for forced non-fast-forward updates).
+
+from::
+	The name of the remote ref being fetched from, minus its
+	`refs/<type>/` prefix. In the case of deletion, the name of
+	the remote ref is "(none)".
+
+to::
+	The name of the local ref being updated, minus its
+	`refs/<type>/` prefix.
+
+reason::
+	A human-readable explanation. In the case of successfully fetched
+	refs, no explanation is needed. For a failed ref, the reason for
+	failure is described.
 
 EXAMPLES
 --------
diff --git a/builtin/fetch.c b/builtin/fetch.c
index f896aa1f88..d9ea6f392a 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -15,6 +15,7 @@
 #include "submodule.h"
 #include "connected.h"
 #include "argv-array.h"
+#include "utf8.h"
 
 static const char * const builtin_fetch_usage[] = {
 	N_("git fetch [<options>] [<repository> [<refspec>...]]"),
@@ -449,7 +450,132 @@ fail:
 			   : STORE_REF_ERROR_OTHER;
 }
 
-#define REFCOL_WIDTH  10
+static int refcol_width = 10;
+static int compact_format;
+
+static void adjust_refcol_width(const struct ref *ref)
+{
+	int max, rlen, llen, len;
+
+	/* uptodate lines are only shown on high verbosity level */
+	if (!verbosity && !oidcmp(&ref->peer_ref->old_oid, &ref->old_oid))
+		return;
+
+	max    = term_columns();
+	rlen   = utf8_strwidth(prettify_refname(ref->name));
+
+	llen   = utf8_strwidth(prettify_refname(ref->peer_ref->name));
+
+	/*
+	 * rough estimation to see if the output line is too long and
+	 * should not be counted (we can't do precise calculation
+	 * anyway because we don't know if the error explanation part
+	 * will be printed in update_local_ref)
+	 */
+	if (compact_format) {
+		llen = 0;
+		max = max * 2 / 3;
+	}
+	len = 21 /* flag and summary */ + rlen + 4 /* -> */ + llen;
+	if (len >= max)
+		return;
+
+	/*
+	 * Not precise calculation for compact mode because '*' can
+	 * appear on the left hand side of '->' and shrink the column
+	 * back.
+	 */
+	if (refcol_width < rlen)
+		refcol_width = rlen;
+}
+
+static void prepare_format_display(struct ref *ref_map)
+{
+	struct ref *rm;
+	const char *format = "full";
+
+	git_config_get_string_const("fetch.output", &format);
+	if (!strcasecmp(format, "full"))
+		compact_format = 0;
+	else if (!strcasecmp(format, "compact"))
+		compact_format = 1;
+	else
+		die(_("configuration fetch.output contains invalid value %s"),
+		    format);
+
+	for (rm = ref_map; rm; rm = rm->next) {
+		if (rm->status == REF_STATUS_REJECT_SHALLOW ||
+		    !rm->peer_ref ||
+		    !strcmp(rm->name, "HEAD"))
+			continue;
+
+		adjust_refcol_width(rm);
+	}
+}
+
+static void print_remote_to_local(struct strbuf *display,
+				  const char *remote, const char *local)
+{
+	strbuf_addf(display, "%-*s -> %s", refcol_width, remote, local);
+}
+
+static int find_and_replace(struct strbuf *haystack,
+			    const char *needle,
+			    const char *placeholder)
+{
+	const char *p = strstr(haystack->buf, needle);
+	int plen, nlen;
+
+	if (!p)
+		return 0;
+
+	if (p > haystack->buf && p[-1] != '/')
+		return 0;
+
+	plen = strlen(p);
+	nlen = strlen(needle);
+	if (plen > nlen && p[nlen] != '/')
+		return 0;
+
+	strbuf_splice(haystack, p - haystack->buf, nlen,
+		      placeholder, strlen(placeholder));
+	return 1;
+}
+
+static void print_compact(struct strbuf *display,
+			  const char *remote, const char *local)
+{
+	struct strbuf r = STRBUF_INIT;
+	struct strbuf l = STRBUF_INIT;
+
+	if (!strcmp(remote, local)) {
+		strbuf_addf(display, "%-*s -> *", refcol_width, remote);
+		return;
+	}
+
+	strbuf_addstr(&r, remote);
+	strbuf_addstr(&l, local);
+
+	if (!find_and_replace(&r, local, "*"))
+		find_and_replace(&l, remote, "*");
+	print_remote_to_local(display, r.buf, l.buf);
+
+	strbuf_release(&r);
+	strbuf_release(&l);
+}
+
+static void format_display(struct strbuf *display, char code,
+			   const char *summary, const char *error,
+			   const char *remote, const char *local)
+{
+	strbuf_addf(display, "%c %-*s ", code, TRANSPORT_SUMMARY(summary));
+	if (!compact_format)
+		print_remote_to_local(display, remote, local);
+	else
+		print_compact(display, remote, local);
+	if (error)
+		strbuf_addf(display, "  (%s)", error);
+}
 
 static int update_local_ref(struct ref *ref,
 			    const char *remote,
@@ -467,9 +593,8 @@ static int update_local_ref(struct ref *ref,
 
 	if (!oidcmp(&ref->old_oid, &ref->new_oid)) {
 		if (verbosity > 0)
-			strbuf_addf(display, "= %-*s %-*s -> %s",
-				    TRANSPORT_SUMMARY(_("[up to date]")),
-				    REFCOL_WIDTH, remote, pretty_ref);
+			format_display(display, '=', _("[up to date]"), NULL,
+				       remote, pretty_ref);
 		return 0;
 	}
 
@@ -481,10 +606,9 @@ static int update_local_ref(struct ref *ref,
 		 * If this is the head, and it's not okay to update
 		 * the head, and the old value of the head isn't empty...
 		 */
-		strbuf_addf(display,
-			    _("! %-*s %-*s -> %s  (can't fetch in current branch)"),
-			    TRANSPORT_SUMMARY(_("[rejected]")),
-			    REFCOL_WIDTH, remote, pretty_ref);
+		format_display(display, '!', _("[rejected]"),
+			       _("can't fetch in current branch"),
+			       remote, pretty_ref);
 		return 1;
 	}
 
@@ -492,11 +616,9 @@ static int update_local_ref(struct ref *ref,
 	    starts_with(ref->name, "refs/tags/")) {
 		int r;
 		r = s_update_ref("updating tag", ref, 0);
-		strbuf_addf(display, "%c %-*s %-*s -> %s%s",
-			    r ? '!' : '-',
-			    TRANSPORT_SUMMARY(_("[tag update]")),
-			    REFCOL_WIDTH, remote, pretty_ref,
-			    r ? _("  (unable to update local ref)") : "");
+		format_display(display, r ? '!' : 't', _("[tag update]"),
+			       r ? _("unable to update local ref") : NULL,
+			       remote, pretty_ref);
 		return r;
 	}
 
@@ -527,11 +649,9 @@ static int update_local_ref(struct ref *ref,
 		    (recurse_submodules != RECURSE_SUBMODULES_ON))
 			check_for_new_submodule_commits(ref->new_oid.hash);
 		r = s_update_ref(msg, ref, 0);
-		strbuf_addf(display, "%c %-*s %-*s -> %s%s",
-			    r ? '!' : '*',
-			    TRANSPORT_SUMMARY(what),
-			    REFCOL_WIDTH, remote, pretty_ref,
-			    r ? _("  (unable to update local ref)") : "");
+		format_display(display, r ? '!' : '*', what,
+			       r ? _("unable to update local ref") : NULL,
+			       remote, pretty_ref);
 		return r;
 	}
 
@@ -545,11 +665,9 @@ static int update_local_ref(struct ref *ref,
 		    (recurse_submodules != RECURSE_SUBMODULES_ON))
 			check_for_new_submodule_commits(ref->new_oid.hash);
 		r = s_update_ref("fast-forward", ref, 1);
-		strbuf_addf(display, "%c %-*s %-*s -> %s%s",
-			    r ? '!' : ' ',
-			    TRANSPORT_SUMMARY_WIDTH, quickref.buf,
-			    REFCOL_WIDTH, remote, pretty_ref,
-			    r ? _("  (unable to update local ref)") : "");
+		format_display(display, r ? '!' : ' ', quickref.buf,
+			       r ? _("unable to update local ref") : NULL,
+			       remote, pretty_ref);
 		strbuf_release(&quickref);
 		return r;
 	} else if (force || ref->force) {
@@ -562,18 +680,14 @@ static int update_local_ref(struct ref *ref,
 		    (recurse_submodules != RECURSE_SUBMODULES_ON))
 			check_for_new_submodule_commits(ref->new_oid.hash);
 		r = s_update_ref("forced-update", ref, 1);
-		strbuf_addf(display, "%c %-*s %-*s -> %s  (%s)",
-			    r ? '!' : '+',
-			    TRANSPORT_SUMMARY_WIDTH, quickref.buf,
-			    REFCOL_WIDTH, remote, pretty_ref,
-			    r ? _("unable to update local ref") : _("forced update"));
+		format_display(display, r ? '!' : '+', quickref.buf,
+			       r ? _("unable to update local ref") : _("forced update"),
+			       remote, pretty_ref);
 		strbuf_release(&quickref);
 		return r;
 	} else {
-		strbuf_addf(display, "! %-*s %-*s -> %s  %s",
-			    TRANSPORT_SUMMARY(_("[rejected]")),
-			    REFCOL_WIDTH, remote, pretty_ref,
-			    _("(non-fast-forward)"));
+		format_display(display, '!', _("[rejected]"), _("non-fast-forward"),
+			       remote, pretty_ref);
 		return 1;
 	}
 }
@@ -620,6 +734,8 @@ static int store_updated_refs(const char *raw_url, const char *remote_name,
 		goto abort;
 	}
 
+	prepare_format_display(ref_map);
+
 	/*
 	 * We do a pass for each fetch_head_status type in their enum order, so
 	 * merged entries are written before not-for-merge. That lets readers
@@ -714,11 +830,10 @@ static int store_updated_refs(const char *raw_url, const char *remote_name,
 				rc |= update_local_ref(ref, what, rm, &note);
 				free(ref);
 			} else
-				strbuf_addf(&note, "* %-*s %-*s -> FETCH_HEAD",
-					    TRANSPORT_SUMMARY_WIDTH,
-					    *kind ? kind : "branch",
-					    REFCOL_WIDTH,
-					    *what ? what : "HEAD");
+				format_display(&note, '*',
+					       *kind ? kind : "branch", NULL,
+					       *what ? what : "HEAD",
+					       "FETCH_HEAD");
 			if (note.len) {
 				if (verbosity >= 0 && !shown_url) {
 					fprintf(stderr, _("From %.*s\n"),
@@ -812,13 +927,15 @@ static int prune_refs(struct refspec *refs, int ref_count, struct ref *ref_map,
 
 	if (verbosity >= 0) {
 		for (ref = stale_refs; ref; ref = ref->next) {
+			struct strbuf sb = STRBUF_INIT;
 			if (!shown_url) {
 				fprintf(stderr, _("From %.*s\n"), url_len, url);
 				shown_url = 1;
 			}
-			fprintf(stderr, " x %-*s %-*s -> %s\n",
-				TRANSPORT_SUMMARY(_("[deleted]")),
-				REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
+			format_display(&sb, '-', _("[deleted]"), NULL,
+				       _("(none)"), prettify_refname(ref->name));
+			fprintf(stderr, " %s\n",sb.buf);
+			strbuf_release(&sb);
 			warn_dangling_symref(stderr, dangling_msg, ref->name);
 		}
 	}
diff --git a/t/t5510-fetch.sh b/t/t5510-fetch.sh
index 88076da1e6..6bd4853079 100755
--- a/t/t5510-fetch.sh
+++ b/t/t5510-fetch.sh
@@ -688,4 +688,34 @@ test_expect_success 'fetching with auto-gc does not lock up' '
 	)
 '
 
+test_expect_success 'fetch aligned output' '
+	git clone . full-output &&
+	test_commit looooooooooooong-tag &&
+	(
+		cd full-output &&
+		git -c fetch.output=full fetch origin 2>&1 | \
+			grep -e "->" | cut -c 22- >../actual
+	) &&
+	cat >expect <<-\EOF &&
+	master               -> origin/master
+	looooooooooooong-tag -> looooooooooooong-tag
+	EOF
+	test_cmp expect actual
+'
+
+test_expect_success 'fetch compact output' '
+	git clone . compact &&
+	test_commit extraaa &&
+	(
+		cd compact &&
+		git -c fetch.output=compact fetch origin 2>&1 | \
+			grep -e "->" | cut -c 22- >../actual
+	) &&
+	cat >expect <<-\EOF &&
+	master     -> origin/*
+	extraaa    -> *
+	EOF
+	test_cmp expect actual
+'
+
 test_done