Merge branch 'jc/t2300-setup' into HEAD

* jc/t2300-setup:
  t2300: run git-sh-setup in an environment that better mimics the real life
  More topics for 2.8.4

Documentation/RelNotes/2.8.4.txt

@@ -24,4 +24,32 @@ Fixes since v2.8.3
  * Many 'linkgit:<git documentation page>' references were broken,
    which are all fixed with this.
 
+ * "git describe --contains" often made a hard-to-justify choice of
+   tag to give name to a given commit, because it tried to come up
+   with a name with smallest number of hops from a tag, causing an old
+   commit whose close descendant that is recently tagged were not
+   described with respect to an old tag but with a newer tag.  It did
+   not help that its computation of "hop" count was further tweaked to
+   penalize being on a side branch of a merge.  The logic has been
+   updated to favor using the tag with the oldest tagger date, which
+   is a lot easier to explain to the end users: "We describe a commit
+   in terms of the (chronologically) oldest tag that contains the
+   commit."
+
+ * Running tests with '-x' option to trace the individual command
+   executions is a useful way to debug test scripts, but some tests
+   that capture the standard error stream and check what the command
+   said can be broken with the trace output mixed in.  When running
+   our tests under "bash", however, we can redirect the trace output
+   to another file descriptor to keep the standard error of programs
+   being tested intact.
+
+ * "http.cookieFile" configuration variable clearly wants a pathname,
+   but we forgot to treat it as such by e.g. applying tilde expansion.
+
+ * When de-initialising all submodules, "git submodule deinit" gave a
+   faulty recommendation to use "git submodule deinit .", which would
+   result in a strange error message in a pathological corner case.
+   This has been corrected to suggest "submodule deinit --all" instead.
+
 Also contains other minor documentation updates and code clean-ups.

t/t2300-cd-to-toplevel.sh

@@ -8,7 +8,8 @@ test_cd_to_toplevel () {
 	test_expect_success $3 "$2" '
 		(
 			cd '"'$1'"' &&
-			. "$(git --exec-path)"/git-sh-setup &&
+			PATH="$(git --exec-path):$PATH" &&
+			. git-sh-setup &&
 			cd_to_toplevel &&
 			[ "$(pwd -P)" = "$TOPLEVEL" ]
 		)