[gjs: 3/9] tools: Update clang-format scripts

[Philip Chimento <pchimento src gnome org>]

commit 7ad357442d78aab68f15001d3af309f4ccf06078
Author: Philip Chimento <philip chimento gmail com>
Date:   Sat Aug 18 16:20:46 2018 -0400

    tools: Update clang-format scripts
    
    A few bugs have been fixed upstream.

 tools/apply-format          |  6 +++---
 tools/git-pre-commit-format | 27 +++++++++++++++++++++++++--
 2 files changed, 28 insertions(+), 5 deletions(-)
---
diff --git a/tools/apply-format b/tools/apply-format
index 9ea3ead5..a601fe58 100755
--- a/tools/apply-format
+++ b/tools/apply-format
@@ -162,7 +162,7 @@ if [ ${#positionals[@]} -gt 0 ]; then
 fi
 
 [ -n "$style" ] || \
-    error_exit "If you use --style you need to speficy a valid style."
+    error_exit "If you use --style you need to specify a valid style."
 
 #######################################
 # Detection of clang-format & friends #
@@ -181,7 +181,7 @@ if [ -z "$format" ]; then
         $'On Ubuntu/Debian this is available in the clang-format package or, in\n' \
         $'older distro versions, clang-format-VERSION.\n' \
         $'On Fedora it\'s available in the clang package.\n' \
-        $'You can also speficy your own path for clang-format by setting the\n' \
+        $'You can also specify your own path for clang-format by setting the\n' \
         $'$CLANG_FORMAT environment variable.'
 fi
 
@@ -249,7 +249,7 @@ if [ "$whole_file" = false ]; then
             $'at https://github.com/barisione/clang-format-hooks/issues with details about\n' \
             $'your operating system and setup.\n' \
             $'\n' \
-            $'You can also speficy your own path for clang-format-diff by setting the\n' \
+            $'You can also specify your own path for clang-format-diff by setting the\n' \
             $'$CLANG_FORMAT_DIFF environment variable, for instance:\n' \
             $'\n' \
             $'    CLANG_FORMAT_DIFF="python /.../clang-format-diff.py" \\\n' \
diff --git a/tools/git-pre-commit-format b/tools/git-pre-commit-format
index 36495093..90fcc334 100755
--- a/tools/git-pre-commit-format
+++ b/tools/git-pre-commit-format
@@ -80,6 +80,7 @@ function rel_realpath() {
 # Find the top-level git directory (taking into account we could be in a submodule).
 declare git_test_dir=.
 declare top_dir
+
 while true; do
     top_dir=$(cd "$git_test_dir" && git rev-parse --show-toplevel) || \
         error_exit "You need to be in the git repository to run this script."
@@ -90,8 +91,30 @@ while true; do
     if [ -d "$top_dir/.git" ]; then
         # We are done! top_dir is the root git directory.
         break
-    else
-        # We are in a submodule if .git is a file!
+    elif [ -f "$top_dir/.git" ]; then
+        # We are in a submodule or git work-tree if .git is a file!
+        if [ -z "$(git rev-parse --show-superproject-working-tree)" ]; then
+            # The --show-superproject-working-tree option is available and we
+            # are in a work tree.
+            gitdir=$(<"$top_dir/.git")
+            gitdir=${gitdir#gitdir: }
+            topdir_basename=${gitdir##*/}
+            git_test_dir=${gitdir%/worktrees/$topdir_basename}
+            break
+        fi
+        # If show-superproject-working-tree returns non-empty string, either:
+        #
+        #   1) --show-superproject-working-tree is not defined for this version of git
+        #
+        #   2) --show-superproject-working-tree is defined and we are in a submodule
+        #
+        # In the first case we will assume it is not a work tree because people
+        # using that advanced technology will be using a recent version of git.
+        #
+        # In second case, we could use the value returned by
+        # --show-superproject-working-tree directly but we do not here because
+        # that would require extra work.
+        #
         git_test_dir="$git_test_dir/.."
     fi
 done