Merge branch 'ep/shell-command-substitution'

Adjust shell scripts to use $(cmd) instead of `cmd`.

* ep/shell-command-substitution: (41 commits)
  t5000-tar-tree.sh: use the $( ... ) construct for command substitution
  t4204-patch-id.sh: use the $( ... ) construct for command substitution
  t4119-apply-config.sh: use the $( ... ) construct for command substitution
  t4116-apply-reverse.sh: use the $( ... ) construct for command substitution
  t4057-diff-combined-paths.sh: use the $( ... ) construct for command substitution
  t4038-diff-combined.sh: use the $( ... ) construct for command substitution
  t4036-format-patch-signer-mime.sh: use the $( ... ) construct for command substitution
  t4014-format-patch.sh: use the $( ... ) construct for command substitution
  t4013-diff-various.sh: use the $( ... ) construct for command substitution
  t4012-diff-binary.sh: use the $( ... ) construct for command substitution
  t4010-diff-pathspec.sh: use the $( ... ) construct for command substitution
  t4006-diff-mode.sh: use the $( ... ) construct for command substitution
  t3910-mac-os-precompose.sh: use the $( ... ) construct for command substitution
  t3905-stash-include-untracked.sh: use the $( ... ) construct for command substitution
  t1050-large.sh: use the $( ... ) construct for command substitution
  t1020-subdirectory.sh: use the $( ... ) construct for command substitution
  t1004-read-tree-m-u-wf.sh: use the $( ... ) construct for command substitution
  t1003-read-tree-prefix.sh: use the $( ... ) construct for command substitution
  t1002-read-tree-m-u-2way.sh: use the $( ... ) construct for command substitution
  t1001-read-tree-m-2way.sh: use the $( ... ) construct for command substitution
  ...

diff --cc contrib/mw-to-git/t/test-gitmw-lib.sh
Simple merge

diff --cc git-rebase--merge.sh
Simple merge

diff --cc git-rebase.sh
Simple merge

diff --cc t/t0001-init.sh
index bbc9cb60ddea49f1ce3f0b0d124f704c30a61346,32821fe450d6116037d092d58db4933bbe6fd0c0..2f3020342a75f0d382af88e6ad35691ad0f183d5
--- 1/t/t0001-init.sh
--- 2/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@@ -180,19 -240,29 +180,19 @@@ test_expect_success 'init with init.tem
  '
  
  test_expect_success 'init --bare/--shared overrides system/global config' '
 -      (
 -              test_config="$HOME"/.gitconfig &&
 -              git config -f "$test_config" core.bare false &&
 -              git config -f "$test_config" core.sharedRepository 0640 &&
 -              mkdir init-bare-shared-override &&
 -              cd init-bare-shared-override &&
 -              git init --bare --shared=0666
 -      ) &&
 +      test_config_global core.bare false &&
 +      test_config_global core.sharedRepository 0640 &&
 +      git init --bare --shared=0666 init-bare-shared-override &&
        check_config init-bare-shared-override true unset &&
        test x0666 = \
-       x`git config -f init-bare-shared-override/config core.sharedRepository`
+       x$(git config -f init-bare-shared-override/config core.sharedRepository)
  '
  
  test_expect_success 'init honors global core.sharedRepository' '
 -      (
 -              test_config="$HOME"/.gitconfig &&
 -              git config -f "$test_config" core.sharedRepository 0666 &&
 -              mkdir shared-honor-global &&
 -              cd shared-honor-global &&
 -              git init
 -      ) &&
 +      test_config_global core.sharedRepository 0666 &&
 +      git init shared-honor-global &&
        test x0666 = \
-       x`git config -f shared-honor-global/.git/config core.sharedRepository`
+       x$(git config -f shared-honor-global/.git/config core.sharedRepository)
  '
  
  test_expect_success 'init rejects insanely long --template' '
@@@ -285,9 -374,9 +285,9 @@@ test_expect_success 'init prefers comma
  test_expect_success 'init with separate gitdir' '
        rm -rf newdir &&
        git init --separate-git-dir realgitdir newdir &&
-       echo "gitdir: `pwd`/realgitdir" >expected &&
+       echo "gitdir: $(pwd)/realgitdir" >expected &&
        test_cmp expected newdir/.git &&
 -      test -d realgitdir/refs
 +      test_path_is_dir realgitdir/refs
  '
  
  test_expect_success 're-init on .git file' '
@@@ -299,10 -388,10 +299,10 @@@ test_expect_success 're-init to update 
        cd newdir &&
        git init --separate-git-dir ../surrealgitdir
        ) &&
-       echo "gitdir: `pwd`/surrealgitdir" >expected &&
+       echo "gitdir: $(pwd)/surrealgitdir" >expected &&
        test_cmp expected newdir/.git &&
 -      test -d surrealgitdir/refs &&
 -      ! test -d realgitdir/refs
 +      test_path_is_dir surrealgitdir/refs &&
 +      test_path_is_missing realgitdir/refs
  '
  
  test_expect_success 're-init to move gitdir' '
@@@ -312,9 -401,9 +312,9 @@@
        cd newdir &&
        git init --separate-git-dir ../realgitdir
        ) &&
-       echo "gitdir: `pwd`/realgitdir" >expected &&
+       echo "gitdir: $(pwd)/realgitdir" >expected &&
        test_cmp expected newdir/.git &&
 -      test -d realgitdir/refs
 +      test_path_is_dir realgitdir/refs
  '
  
  test_expect_success SYMLINKS 're-init to move gitdir symlink' '
@@@ -326,10 -415,10 +326,10 @@@
        ln -s here .git &&
        git init --separate-git-dir ../realgitdir
        ) &&
-       echo "gitdir: `pwd`/realgitdir" >expected &&
+       echo "gitdir: $(pwd)/realgitdir" >expected &&
        test_cmp expected newdir/.git &&
 -      test -d realgitdir/refs &&
 -      ! test -d newdir/here
 +      test_cmp expected newdir/here &&
 +      test_path_is_dir realgitdir/refs
  '
  
  test_done

diff --cc t/t1001-read-tree-m-2way.sh
Simple merge

diff --cc t/t4014-format-patch.sh
Simple merge