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
  ...

32 files changed, 151 insertions, 151 deletions

diff --git a/t/lib-credential.sh b/t/lib-credential.sh
index 957ae93..9e7d796 100755
--- a/t/lib-credential.sh
+++ b/t/lib-credential.sh
@@ -281,7 +281,7 @@ helper_test_timeout() {
 cat >askpass <<\EOF
 #!/bin/sh
 echo >&2 askpass: $*
-what=`echo $1 | cut -d" " -f1 | tr A-Z a-z | tr -cd a-z`
+what=$(echo $1 | cut -d" " -f1 | tr A-Z a-z | tr -cd a-z)
 echo "askpass-$what"
 EOF
 chmod +x askpass
diff --git a/t/lib-cvs.sh b/t/lib-cvs.sh
index 5076718..9b2bcfb 100644
--- a/t/lib-cvs.sh
+++ b/t/lib-cvs.sh
@@ -13,7 +13,7 @@ fi
 CVS="cvs -f"
 export CVS
 
-cvsps_version=`cvsps -h 2>&1 | sed -ne 's/cvsps version //p'`
+cvsps_version=$(cvsps -h 2>&1 | sed -ne 's/cvsps version //p')
 case "$cvsps_version" in
 2.1 | 2.2*)
 	;;
diff --git a/t/lib-gpg.sh b/t/lib-gpg.sh
index 05824fa..fd499e7 100755
--- a/t/lib-gpg.sh
+++ b/t/lib-gpg.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-gpg_version=`gpg --version 2>&1`
+gpg_version=$(gpg --version 2>&1)
 if test $? = 127; then
 	say "You do not seem to have gpg installed"
 else
diff --git a/t/perf/p5302-pack-index.sh b/t/perf/p5302-pack-index.sh
index 6cb5b0d..5ee9211 100755
--- a/t/perf/p5302-pack-index.sh
+++ b/t/perf/p5302-pack-index.sh
@@ -8,7 +8,7 @@ test_perf_large_repo
 
 test_expect_success 'repack' '
 	git repack -ad &&
-	PACK=`ls .git/objects/pack/*.pack | head -n1` &&
+	PACK=$(ls .git/objects/pack/*.pack | head -n1) &&
 	test -f "$PACK" &&
 	export PACK
 '
diff --git a/t/t0001-init.sh b/t/t0001-init.sh
index bbc9cb6..2f30203 100755
--- a/t/t0001-init.sh
+++ b/t/t0001-init.sh
@@ -185,14 +185,14 @@ test_expect_success 'init --bare/--shared overrides system/global config' '
 	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_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' '
@@ -285,7 +285,7 @@ test_expect_success 'init prefers command line to GIT_DIR' '
 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_path_is_dir realgitdir/refs
 '
@@ -299,7 +299,7 @@ test_expect_success 're-init to update git link' '
 	cd newdir &&
 	git init --separate-git-dir ../surrealgitdir
 	) &&
-	echo "gitdir: `pwd`/surrealgitdir" >expected &&
+	echo "gitdir: $(pwd)/surrealgitdir" >expected &&
 	test_cmp expected newdir/.git &&
 	test_path_is_dir surrealgitdir/refs &&
 	test_path_is_missing realgitdir/refs
@@ -312,7 +312,7 @@ test_expect_success 're-init to move gitdir' '
 	cd newdir &&
 	git init --separate-git-dir ../realgitdir
 	) &&
-	echo "gitdir: `pwd`/realgitdir" >expected &&
+	echo "gitdir: $(pwd)/realgitdir" >expected &&
 	test_cmp expected newdir/.git &&
 	test_path_is_dir realgitdir/refs
 '
@@ -326,7 +326,7 @@ test_expect_success SYMLINKS 're-init to move gitdir symlink' '
 	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_cmp expected newdir/here &&
 	test_path_is_dir realgitdir/refs
diff --git a/t/t0010-racy-git.sh b/t/t0010-racy-git.sh
index e45a9e4..5657c5a 100755
--- a/t/t0010-racy-git.sh
+++ b/t/t0010-racy-git.sh
@@ -14,7 +14,7 @@ do
 	git update-index --add infocom
 	echo xyzzy >infocom
 
-	files=`git diff-files -p`
+	files=$(git diff-files -p)
 	test_expect_success \
 	"Racy GIT trial #$trial part A" \
 	'test "" != "$files"'
@@ -23,7 +23,7 @@ do
 	echo xyzzy >cornerstone
 	git update-index --add cornerstone
 
-	files=`git diff-files -p`
+	files=$(git diff-files -p)
 	test_expect_success \
 	"Racy GIT trial #$trial part B" \
 	'test "" != "$files"'
diff --git a/t/t0020-crlf.sh b/t/t0020-crlf.sh
index e526184..d2e51a8 100755
--- a/t/t0020-crlf.sh
+++ b/t/t0020-crlf.sh
@@ -20,14 +20,14 @@ test_expect_success setup '
 
 	git commit -m initial &&
 
-	one=`git rev-parse HEAD:one` &&
-	dir=`git rev-parse HEAD:dir` &&
-	two=`git rev-parse HEAD:dir/two` &&
-	three=`git rev-parse HEAD:three` &&
+	one=$(git rev-parse HEAD:one) &&
+	dir=$(git rev-parse HEAD:dir) &&
+	two=$(git rev-parse HEAD:dir/two) &&
+	three=$(git rev-parse HEAD:three) &&
 
 	for w in Some extra lines here; do echo $w; done >>one &&
 	git diff >patch.file &&
-	patched=`git hash-object --stdin <one` &&
+	patched=$(git hash-object --stdin <one) &&
 	git read-tree --reset -u HEAD &&
 
 	echo happy.
@@ -111,7 +111,7 @@ test_expect_success 'update with autocrlf=input' '
 		}
 	done &&
 
-	differs=`git diff-index --cached HEAD` &&
+	differs=$(git diff-index --cached HEAD) &&
 	test -z "$differs" || {
 		echo Oops "$differs"
 		false
@@ -135,7 +135,7 @@ test_expect_success 'update with autocrlf=true' '
 		}
 	done &&
 
-	differs=`git diff-index --cached HEAD` &&
+	differs=$(git diff-index --cached HEAD) &&
 	test -z "$differs" || {
 		echo Oops "$differs"
 		false
@@ -158,9 +158,9 @@ test_expect_success 'checkout with autocrlf=true' '
 			break
 		}
 	done &&
-	test "$one" = `git hash-object --stdin <one` &&
-	test "$two" = `git hash-object --stdin <dir/two` &&
-	differs=`git diff-index --cached HEAD` &&
+	test "$one" = $(git hash-object --stdin <one) &&
+	test "$two" = $(git hash-object --stdin <dir/two) &&
+	differs=$(git diff-index --cached HEAD) &&
 	test -z "$differs" || {
 		echo Oops "$differs"
 		false
@@ -184,9 +184,9 @@ test_expect_success 'checkout with autocrlf=input' '
 			git update-index -- $f
 		fi
 	done &&
-	test "$one" = `git hash-object --stdin <one` &&
-	test "$two" = `git hash-object --stdin <dir/two` &&
-	differs=`git diff-index --cached HEAD` &&
+	test "$one" = $(git hash-object --stdin <one) &&
+	test "$two" = $(git hash-object --stdin <dir/two) &&
+	differs=$(git diff-index --cached HEAD) &&
 	test -z "$differs" || {
 		echo Oops "$differs"
 		false
@@ -200,7 +200,7 @@ test_expect_success 'apply patch (autocrlf=input)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply patch.file &&
-	test "$patched" = "`git hash-object --stdin <one`" || {
+	test "$patched" = "$(git hash-object --stdin <one)" || {
 		echo "Eh?  apply without index"
 		false
 	}
@@ -213,7 +213,7 @@ test_expect_success 'apply patch --cached (autocrlf=input)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply --cached patch.file &&
-	test "$patched" = `git rev-parse :one` || {
+	test "$patched" = $(git rev-parse :one) || {
 		echo "Eh?  apply with --cached"
 		false
 	}
@@ -226,8 +226,8 @@ test_expect_success 'apply patch --index (autocrlf=input)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply --index patch.file &&
-	test "$patched" = `git rev-parse :one` &&
-	test "$patched" = `git hash-object --stdin <one` || {
+	test "$patched" = $(git rev-parse :one) &&
+	test "$patched" = $(git hash-object --stdin <one) || {
 		echo "Eh?  apply with --index"
 		false
 	}
@@ -240,7 +240,7 @@ test_expect_success 'apply patch (autocrlf=true)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply patch.file &&
-	test "$patched" = "`remove_cr <one | git hash-object --stdin`" || {
+	test "$patched" = "$(remove_cr <one | git hash-object --stdin)" || {
 		echo "Eh?  apply without index"
 		false
 	}
@@ -253,7 +253,7 @@ test_expect_success 'apply patch --cached (autocrlf=true)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply --cached patch.file &&
-	test "$patched" = `git rev-parse :one` || {
+	test "$patched" = $(git rev-parse :one) || {
 		echo "Eh?  apply without index"
 		false
 	}
@@ -266,8 +266,8 @@ test_expect_success 'apply patch --index (autocrlf=true)' '
 	git read-tree --reset -u HEAD &&
 
 	git apply --index patch.file &&
-	test "$patched" = `git rev-parse :one` &&
-	test "$patched" = "`remove_cr <one | git hash-object --stdin`" || {
+	test "$patched" = $(git rev-parse :one) &&
+	test "$patched" = "$(remove_cr <one | git hash-object --stdin)" || {
 		echo "Eh?  apply with --index"
 		false
 	}
diff --git a/t/t0025-crlf-auto.sh b/t/t0025-crlf-auto.sh
index f5f67a6..b0e5694 100755
--- a/t/t0025-crlf-auto.sh
+++ b/t/t0025-crlf-auto.sh
@@ -19,9 +19,9 @@ test_expect_success setup '
 
 	git commit -m initial &&
 
-	one=`git rev-parse HEAD:one` &&
-	two=`git rev-parse HEAD:two` &&
-	three=`git rev-parse HEAD:three` &&
+	one=$(git rev-parse HEAD:one) &&
+	two=$(git rev-parse HEAD:two) &&
+	three=$(git rev-parse HEAD:three) &&
 
 	echo happy.
 '
@@ -33,9 +33,9 @@ test_expect_success 'default settings cause no changes' '
 
 	! has_cr one &&
 	has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
-	threediff=`git diff three` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
+	threediff=$(git diff three) &&
 	test -z "$onediff" -a -z "$twodiff" -a -z "$threediff"
 '
 
@@ -48,7 +48,7 @@ test_expect_success 'crlf=true causes a CRLF file to be normalized' '
 
 	# Note, "normalized" means that git will normalize it if added
 	has_cr two &&
-	twodiff=`git diff two` &&
+	twodiff=$(git diff two) &&
 	test -n "$twodiff"
 '
 
@@ -60,7 +60,7 @@ test_expect_success 'text=true causes a CRLF file to be normalized' '
 
 	# Note, "normalized" means that git will normalize it if added
 	has_cr two &&
-	twodiff=`git diff two` &&
+	twodiff=$(git diff two) &&
 	test -n "$twodiff"
 '
 
@@ -72,7 +72,7 @@ test_expect_success 'eol=crlf gives a normalized file CRLFs with autocrlf=false'
 	git read-tree --reset -u HEAD &&
 
 	has_cr one &&
-	onediff=`git diff one` &&
+	onediff=$(git diff one) &&
 	test -z "$onediff"
 '
 
@@ -84,7 +84,7 @@ test_expect_success 'eol=crlf gives a normalized file CRLFs with autocrlf=input'
 	git read-tree --reset -u HEAD &&
 
 	has_cr one &&
-	onediff=`git diff one` &&
+	onediff=$(git diff one) &&
 	test -z "$onediff"
 '
 
@@ -96,7 +96,7 @@ test_expect_success 'eol=lf gives a normalized file LFs with autocrlf=true' '
 	git read-tree --reset -u HEAD &&
 
 	! has_cr one &&
-	onediff=`git diff one` &&
+	onediff=$(git diff one) &&
 	test -z "$onediff"
 '
 
@@ -108,9 +108,9 @@ test_expect_success 'autocrlf=true does not normalize CRLF files' '
 
 	has_cr one &&
 	has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
-	threediff=`git diff three` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
+	threediff=$(git diff three) &&
 	test -z "$onediff" -a -z "$twodiff" -a -z "$threediff"
 '
 
@@ -123,9 +123,9 @@ test_expect_success 'text=auto, autocrlf=true _does_ normalize CRLF files' '
 
 	has_cr one &&
 	has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
-	threediff=`git diff three` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
+	threediff=$(git diff three) &&
 	test -z "$onediff" -a -n "$twodiff" -a -z "$threediff"
 '
 
@@ -137,7 +137,7 @@ test_expect_success 'text=auto, autocrlf=true does not normalize binary files' '
 	git read-tree --reset -u HEAD &&
 
 	! has_cr three &&
-	threediff=`git diff three` &&
+	threediff=$(git diff three) &&
 	test -z "$threediff"
 '
 
@@ -148,7 +148,7 @@ test_expect_success 'eol=crlf _does_ normalize binary files' '
 	git read-tree --reset -u HEAD &&
 
 	has_cr three &&
-	threediff=`git diff three` &&
+	threediff=$(git diff three) &&
 	test -z "$threediff"
 '
 
diff --git a/t/t0026-eol-config.sh b/t/t0026-eol-config.sh
index fe0164b..e1126aa 100755
--- a/t/t0026-eol-config.sh
+++ b/t/t0026-eol-config.sh
@@ -20,8 +20,8 @@ test_expect_success setup '
 
 	git commit -m initial &&
 
-	one=`git rev-parse HEAD:one` &&
-	two=`git rev-parse HEAD:two` &&
+	one=$(git rev-parse HEAD:one) &&
+	two=$(git rev-parse HEAD:two) &&
 
 	echo happy.
 '
@@ -34,8 +34,8 @@ test_expect_success 'eol=lf puts LFs in normalized file' '
 
 	! has_cr one &&
 	! has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
 	test -z "$onediff" -a -z "$twodiff"
 '
 
@@ -47,8 +47,8 @@ test_expect_success 'eol=crlf puts CRLFs in normalized file' '
 
 	has_cr one &&
 	! has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
 	test -z "$onediff" -a -z "$twodiff"
 '
 
@@ -61,8 +61,8 @@ test_expect_success 'autocrlf=true overrides eol=lf' '
 
 	has_cr one &&
 	has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
 	test -z "$onediff" -a -z "$twodiff"
 '
 
@@ -75,8 +75,8 @@ test_expect_success 'autocrlf=true overrides unset eol' '
 
 	has_cr one &&
 	has_cr two &&
-	onediff=`git diff one` &&
-	twodiff=`git diff two` &&
+	onediff=$(git diff one) &&
+	twodiff=$(git diff two) &&
 	test -z "$onediff" -a -z "$twodiff"
 '
 
diff --git a/t/t0030-stripspace.sh b/t/t0030-stripspace.sh
index a8e84d8..0333dd9 100755
--- a/t/t0030-stripspace.sh
+++ b/t/t0030-stripspace.sh
@@ -225,22 +225,22 @@ test_expect_success \
 
 test_expect_success \
     'text without newline at end should end with newline' '
-    test `printf "$ttt" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt$ttt" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt$ttt$ttt" | git stripspace | wc -l` -gt 0
+    test $(printf "$ttt" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt$ttt" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt$ttt$ttt" | git stripspace | wc -l) -gt 0
 '
 
 # text plus spaces at the end:
 
 test_expect_success \
     'text plus spaces without newline at end should end with newline' '
-    test `printf "$ttt$sss" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt$sss" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt$ttt$sss" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$sss$sss" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$ttt$sss$sss" | git stripspace | wc -l` -gt 0 &&
-    test `printf "$ttt$sss$sss$sss" | git stripspace | wc -l` -gt 0
+    test $(printf "$ttt$sss" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt$sss" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt$ttt$sss" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$sss$sss" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$ttt$sss$sss" | git stripspace | wc -l) -gt 0 &&
+    test $(printf "$ttt$sss$sss$sss" | git stripspace | wc -l) -gt 0
 '
 
 test_expect_success \
diff --git a/t/t0300-credentials.sh b/t/t0300-credentials.sh
index 538ea5f..57ea5a1 100755
--- a/t/t0300-credentials.sh
+++ b/t/t0300-credentials.sh
@@ -6,7 +6,7 @@ test_description='basic credential helper tests'
 
 test_expect_success 'setup helper scripts' '
 	cat >dump <<-\EOF &&
-	whoami=`echo $0 | sed s/.*git-credential-//`
+	whoami=$(echo $0 | sed s/.*git-credential-//)
 	echo >&2 "$whoami: $*"
 	OIFS=$IFS
 	IFS==
diff --git a/t/t1000-read-tree-m-3way.sh b/t/t1000-read-tree-m-3way.sh
index babcdd2..a0b79b4 100755
--- a/t/t1000-read-tree-m-3way.sh
+++ b/t/t1000-read-tree-m-3way.sh
@@ -519,10 +519,10 @@ test_expect_success \
     'rm -f .git/index F16 &&
     echo F16 >F16 &&
     git update-index --add F16 &&
-    tree0=`git write-tree` &&
+    tree0=$(git write-tree) &&
     echo E16 >F16 &&
     git update-index F16 &&
-    tree1=`git write-tree` &&
+    tree1=$(git write-tree) &&
     read_tree_must_succeed -m $tree0 $tree1 $tree1 $tree0 &&
     git ls-files --stage'
 
diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh
index 3a24abf..db1b6f5 100755
--- a/t/t1001-read-tree-m-2way.sh
+++ b/t/t1001-read-tree-m-2way.sh
@@ -36,7 +36,7 @@ compare_change () {
 }
 
 check_cache_at () {
-	clean_if_empty=`git diff-files -- "$1"`
+	clean_if_empty=$(git diff-files -- "$1")
 	case "$clean_if_empty" in
 	'')  echo "$1: clean" ;;
 	?*)  echo "$1: dirty" ;;
@@ -68,14 +68,14 @@ test_expect_success \
      echo rezrov >rezrov &&
      echo yomin >yomin &&
      git update-index --add nitfol bozbar rezrov &&
-     treeH=`git write-tree` &&
+     treeH=$(git write-tree) &&
      echo treeH $treeH &&
      git ls-tree $treeH &&
 
      cat bozbar-new >bozbar &&
      git update-index --add frotz bozbar --force-remove rezrov &&
      git ls-files --stage >M.out &&
-     treeM=`git write-tree` &&
+     treeM=$(git write-tree) &&
      echo treeM $treeM &&
      git ls-tree $treeM &&
      git diff-tree $treeH $treeM'
@@ -315,7 +315,7 @@ test_expect_success \
     'rm -f .git/index &&
      echo DF >DF &&
      git update-index --add DF &&
-     treeDF=`git write-tree` &&
+     treeDF=$(git write-tree) &&
      echo treeDF $treeDF &&
      git ls-tree $treeDF &&
 
@@ -323,7 +323,7 @@ test_expect_success \
      mkdir DF &&
      echo DF/DF >DF/DF &&
      git update-index --add --remove DF DF/DF &&
-     treeDFDF=`git write-tree` &&
+     treeDFDF=$(git write-tree) &&
      echo treeDFDF $treeDFDF &&
      git ls-tree $treeDFDF &&
      git ls-files --stage >DFDF.out'
@@ -345,7 +345,7 @@ test_expect_success \
     'rm -f .git/index &&
      : >a &&
      git update-index --add a &&
-     treeM=`git write-tree` &&
+     treeM=$(git write-tree) &&
      echo treeM $treeM &&
      git ls-tree $treeM &&
      git ls-files --stage >treeM.out &&
@@ -354,7 +354,7 @@ test_expect_success \
      git update-index --remove a &&
      mkdir a &&
      : >a/b &&
-     treeH=`git write-tree` &&
+     treeH=$(git write-tree) &&
      echo treeH $treeH &&
      git ls-tree $treeH'
 
@@ -372,7 +372,7 @@ test_expect_success \
      mkdir c &&
      : >c/d &&
      git update-index --add a c/d &&
-     treeM=`git write-tree` &&
+     treeM=$(git write-tree) &&
      echo treeM $treeM &&
      git ls-tree $treeM &&
      git ls-files --stage >treeM.out &&
@@ -381,7 +381,7 @@ test_expect_success \
      mkdir a &&
      : >a/b &&
      git update-index --add --remove a a/b &&
-     treeH=`git write-tree` &&
+     treeH=$(git write-tree) &&
      echo treeH $treeH &&
      git ls-tree $treeH'
 
diff --git a/t/t1002-read-tree-m-u-2way.sh b/t/t1002-read-tree-m-u-2way.sh
index a847709..fed877b 100755
--- a/t/t1002-read-tree-m-u-2way.sh
+++ b/t/t1002-read-tree-m-u-2way.sh
@@ -21,7 +21,7 @@ compare_change () {
 }
 
 check_cache_at () {
-	clean_if_empty=`git diff-files -- "$1"`
+	clean_if_empty=$(git diff-files -- "$1")
 	case "$clean_if_empty" in
 	'')  echo "$1: clean" ;;
 	?*)  echo "$1: dirty" ;;
@@ -41,14 +41,14 @@ test_expect_success \
      echo bozbar >bozbar &&
      echo rezrov >rezrov &&
      git update-index --add nitfol bozbar rezrov &&
-     treeH=`git write-tree` &&
+     treeH=$(git write-tree) &&
      echo treeH $treeH &&
      git ls-tree $treeH &&
 
      echo gnusto >bozbar &&
      git update-index --add frotz bozbar --force-remove rezrov &&
      git ls-files --stage >M.out &&
-     treeM=`git write-tree` &&
+     treeM=$(git write-tree) &&
      echo treeM $treeM &&
      git ls-tree $treeM &&
      sum bozbar frotz nitfol >M.sum &&
@@ -318,7 +318,7 @@ test_expect_success \
     'rm -f .git/index &&
      echo DF >DF &&
      git update-index --add DF &&
-     treeDF=`git write-tree` &&
+     treeDF=$(git write-tree) &&
      echo treeDF $treeDF &&
      git ls-tree $treeDF &&
 
@@ -326,7 +326,7 @@ test_expect_success \
      mkdir DF &&
      echo DF/DF >DF/DF &&
      git update-index --add --remove DF DF/DF &&
-     treeDFDF=`git write-tree` &&
+     treeDFDF=$(git write-tree) &&
      echo treeDFDF $treeDFDF &&
      git ls-tree $treeDFDF &&
      git ls-files --stage >DFDF.out'
diff --git a/t/t1003-read-tree-prefix.sh b/t/t1003-read-tree-prefix.sh
index 8c6d67e..b6111cd 100755
--- a/t/t1003-read-tree-prefix.sh
+++ b/t/t1003-read-tree-prefix.sh
@@ -11,7 +11,7 @@ test_description='git read-tree --prefix test.
 test_expect_success setup '
 	echo hello >one &&
 	git update-index --add one &&
-	tree=`git write-tree` &&
+	tree=$(git write-tree) &&
 	echo tree is $tree
 '
 
diff --git a/t/t1004-read-tree-m-u-wf.sh b/t/t1004-read-tree-m-u-wf.sh
index 3e72aff..c70cf42 100755
--- a/t/t1004-read-tree-m-u-wf.sh
+++ b/t/t1004-read-tree-m-u-wf.sh
@@ -30,7 +30,7 @@ test_expect_success 'two-way not clobbering' '
 
 	echo >file2 master creates untracked file2 &&
 	echo >subdir/file2 master creates untracked subdir/file2 &&
-	if err=`read_tree_u_must_succeed -m -u master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -43,7 +43,7 @@ echo file2 >.gitignore
 
 test_expect_success 'two-way with incorrect --exclude-per-directory (1)' '
 
-	if err=`read_tree_u_must_succeed -m --exclude-per-directory=.gitignore master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m --exclude-per-directory=.gitignore master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -54,7 +54,7 @@ test_expect_success 'two-way with incorrect --exclude-per-directory (1)' '
 
 test_expect_success 'two-way with incorrect --exclude-per-directory (2)' '
 
-	if err=`read_tree_u_must_succeed -m -u --exclude-per-directory=foo --exclude-per-directory=.gitignore master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u --exclude-per-directory=foo --exclude-per-directory=.gitignore master side 2>&1)
 	then
 		echo should have complained
 		false
@@ -95,7 +95,7 @@ test_expect_success 'three-way not clobbering a working tree file' '
 	git checkout master &&
 	echo >file3 file three created in master, untracked &&
 	echo >subdir/file3 file three created in master, untracked &&
-	if err=`read_tree_u_must_succeed -m -u branch-point master side 2>&1`
+	if err=$(read_tree_u_must_succeed -m -u branch-point master side 2>&1)
 	then
 		echo should have complained
 		false
diff --git a/t/t1020-subdirectory.sh b/t/t1020-subdirectory.sh
index 6902320..62c0d25 100755
--- a/t/t1020-subdirectory.sh
+++ b/t/t1020-subdirectory.sh
@@ -20,27 +20,27 @@ test_expect_success setup '
 
 test_expect_success 'update-index and ls-files' '
 	git update-index --add one &&
-	case "`git ls-files`" in
+	case "$(git ls-files)" in
 	one) echo pass one ;;
 	*) echo bad one; exit 1 ;;
 	esac &&
 	(
 		cd dir &&
 		git update-index --add two &&
-		case "`git ls-files`" in
+		case "$(git ls-files)" in
 		two) echo pass two ;;
 		*) echo bad two; exit 1 ;;
 		esac
 	) &&
-	case "`git ls-files`" in
+	case "$(git ls-files)" in
 	dir/two"$LF"one) echo pass both ;;
 	*) echo bad; exit 1 ;;
 	esac
 '
 
 test_expect_success 'cat-file' '
-	two=`git ls-files -s dir/two` &&
-	two=`expr "$two" : "[0-7]* \\([0-9a-f]*\\)"` &&
+	two=$(git ls-files -s dir/two) &&
+	two=$(expr "$two" : "[0-7]* \\([0-9a-f]*\\)") &&
 	echo "$two" &&
 	git cat-file -p "$two" >actual &&
 	cmp dir/two actual &&
@@ -55,18 +55,18 @@ rm -f actual dir/actual
 test_expect_success 'diff-files' '
 	echo a >>one &&
 	echo d >>dir/two &&
-	case "`git diff-files --name-only`" in
+	case "$(git diff-files --name-only)" in
 	dir/two"$LF"one) echo pass top ;;
 	*) echo bad top; exit 1 ;;
 	esac &&
 	# diff should not omit leading paths
 	(
 		cd dir &&
-		case "`git diff-files --name-only`" in
+		case "$(git diff-files --name-only)" in
 		dir/two"$LF"one) echo pass subdir ;;
 		*) echo bad subdir; exit 1 ;;
 		esac &&
-		case "`git diff-files --name-only .`" in
+		case "$(git diff-files --name-only .)" in
 		dir/two) echo pass subdir limited ;;
 		*) echo bad subdir limited; exit 1 ;;
 		esac
@@ -74,11 +74,11 @@ test_expect_success 'diff-files' '
 '
 
 test_expect_success 'write-tree' '
-	top=`git write-tree` &&
+	top=$(git write-tree) &&
 	echo $top &&
 	(
 		cd dir &&
-		sub=`git write-tree` &&
+		sub=$(git write-tree) &&
 		echo $sub &&
 		test "z$top" = "z$sub"
 	)
@@ -96,7 +96,7 @@ test_expect_success 'checkout-index' '
 
 test_expect_success 'read-tree' '
 	rm -f one dir/two &&
-	tree=`git write-tree` &&
+	tree=$(git write-tree) &&
 	read_tree_u_must_succeed --reset -u "$tree" &&
 	cmp one original.one &&
 	cmp dir/two original.two &&
diff --git a/t/t1050-large.sh b/t/t1050-large.sh
index fd10528..aea4936 100755
--- a/t/t1050-large.sh
+++ b/t/t1050-large.sh
@@ -131,7 +131,7 @@ test_expect_success 'git-show a large file' '
 '
 
 test_expect_success 'index-pack' '
-	git clone file://"`pwd`"/.git foo &&
+	git clone file://"$(pwd)"/.git foo &&
 	GIT_DIR=non-existent git index-pack --strict --verify foo/.git/objects/pack/*.pack
 '
 
@@ -140,7 +140,7 @@ test_expect_success 'repack' '
 '
 
 test_expect_success 'pack-objects with large loose object' '
-	SHA1=`git hash-object huge` &&
+	SHA1=$(git hash-object huge) &&
 	test_create_repo loose &&
 	echo $SHA1 | git pack-objects --stdout |
 		GIT_ALLOC_LIMIT=0 GIT_DIR=loose/.git git unpack-objects &&
diff --git a/t/t3905-stash-include-untracked.sh b/t/t3905-stash-include-untracked.sh
index a5e7e6b..f372fc8 100755
--- a/t/t3905-stash-include-untracked.sh
+++ b/t/t3905-stash-include-untracked.sh
@@ -96,8 +96,8 @@ test_expect_success 'stash pop after save --include-untracked leaves files untra
 	git stash pop &&
 	git status --porcelain >actual &&
 	test_cmp expect actual &&
-	test "1" = "`cat file2`" &&
-	test untracked = "`cat untracked/untracked`"
+	test "1" = "$(cat file2)" &&
+	test untracked = "$(cat untracked/untracked)"
 '
 
 git clean --force --quiet -d
diff --git a/t/t3910-mac-os-precompose.sh b/t/t3910-mac-os-precompose.sh
index e4ba601..96941e9 100755
--- a/t/t3910-mac-os-precompose.sh
+++ b/t/t3910-mac-os-precompose.sh
@@ -14,13 +14,13 @@ then
 fi
 
 # create utf-8 variables
-Adiarnfc=`printf '\303\204'`
-Adiarnfd=`printf 'A\314\210'`
+Adiarnfc=$(printf '\303\204')
+Adiarnfd=$(printf 'A\314\210')
 
-Odiarnfc=`printf '\303\226'`
-Odiarnfd=`printf 'O\314\210'`
-AEligatu=`printf '\303\206'`
-Invalidu=`printf '\303\377'`
+Odiarnfc=$(printf '\303\226')
+Odiarnfd=$(printf 'O\314\210')
+AEligatu=$(printf '\303\206')
+Invalidu=$(printf '\303\377')
 
 
 #Create a string with 255 bytes (decomposed)
@@ -35,7 +35,7 @@ Alongc=$Alongc$Alongc$Alongc$Alongc$Alongc           #250 Byte
 Alongc=$Alongc$AEligatu$AEligatu                     #254 Byte
 
 test_expect_success "detect if nfd needed" '
-	precomposeunicode=`git config core.precomposeunicode` &&
+	precomposeunicode=$(git config core.precomposeunicode) &&
 	test "$precomposeunicode" = true &&
 	git config core.precomposeunicode true
 '
@@ -146,7 +146,7 @@ test_expect_success "respect git config --global core.precomposeunicode" '
 	git config --global core.precomposeunicode true &&
 	rm -rf .git &&
 	git init &&
-	precomposeunicode=`git config core.precomposeunicode` &&
+	precomposeunicode=$(git config core.precomposeunicode) &&
 	test "$precomposeunicode" = "true"
 '
 
diff --git a/t/t4006-diff-mode.sh b/t/t4006-diff-mode.sh
index 0591149..76f643b 100755
--- a/t/t4006-diff-mode.sh
+++ b/t/t4006-diff-mode.sh
@@ -13,7 +13,7 @@ sed_script='s/\(:100644 100755\) \('"$_x40"'\) \2 /\1 X X /'
 test_expect_success 'setup' '
 	echo frotz >rezrov &&
 	git update-index --add rezrov &&
-	tree=`git write-tree` &&
+	tree=$(git write-tree) &&
 	echo $tree
 '
 
diff --git a/t/t4010-diff-pathspec.sh b/t/t4010-diff-pathspec.sh
index 2bb9736..bf07841 100755
--- a/t/t4010-diff-pathspec.sh
+++ b/t/t4010-diff-pathspec.sh
@@ -18,7 +18,7 @@ test_expect_success \
      mkdir path1 &&
      echo rezrov >path1/file1 &&
      git update-index --add file0 path1/file1 &&
-     tree=`git write-tree` &&
+     tree=$(git write-tree) &&
      echo "$tree" &&
      echo nitfol >file0 &&
      echo yomin >path1/file1 &&
@@ -131,7 +131,7 @@ test_expect_success 'diff multiple wildcard pathspecs' '
 	mkdir path2 &&
 	echo rezrov >path2/file1 &&
 	git update-index --add path2/file1 &&
-	tree3=`git write-tree` &&
+	tree3=$(git write-tree) &&
 	git diff --name-only $tree $tree3 -- "path2*1" "path1*1" >actual &&
 	cat <<-\EOF >expect &&
 	path1/file1
diff --git a/t/t4012-diff-binary.sh b/t/t4012-diff-binary.sh
index 1215ae5..643d729 100755
--- a/t/t4012-diff-binary.sh
+++ b/t/t4012-diff-binary.sh
@@ -67,18 +67,18 @@ test_expect_success C_LOCALE_OUTPUT 'apply detecting corrupt patch correctly' '
 	git diff >output &&
 	sed -e "s/-CIT/xCIT/" <output >broken &&
 	test_must_fail git apply --stat --summary broken 2>detected &&
-	detected=`cat detected` &&
-	detected=`expr "$detected" : "fatal.*at line \\([0-9]*\\)\$"` &&
-	detected=`sed -ne "${detected}p" broken` &&
+	detected=$(cat detected) &&
+	detected=$(expr "$detected" : "fatal.*at line \\([0-9]*\\)\$") &&
+	detected=$(sed -ne "${detected}p" broken) &&
 	test "$detected" = xCIT
 '
 
 test_expect_success C_LOCALE_OUTPUT 'apply detecting corrupt patch correctly' '
 	git diff --binary | sed -e "s/-CIT/xCIT/" >broken &&
 	test_must_fail git apply --stat --summary broken 2>detected &&
-	detected=`cat detected` &&
-	detected=`expr "$detected" : "fatal.*at line \\([0-9]*\\)\$"` &&
-	detected=`sed -ne "${detected}p" broken` &&
+	detected=$(cat detected) &&
+	detected=$(expr "$detected" : "fatal.*at line \\([0-9]*\\)\$") &&
+	detected=$(sed -ne "${detected}p" broken) &&
 	test "$detected" = xCIT
 '
 
@@ -88,7 +88,7 @@ test_expect_success 'initial commit' 'git commit -a -m initial'
 test_expect_success 'diff-index with --binary' '
 	echo AIT >a && mv b e && echo CIT >c && cat e >d &&
 	git update-index --add --remove a b c d e &&
-	tree0=`git write-tree` &&
+	tree0=$(git write-tree) &&
 	git diff --cached --binary >current &&
 	git apply --stat --summary current
 '
@@ -96,7 +96,7 @@ test_expect_success 'diff-index with --binary' '
 test_expect_success 'apply binary patch' '
 	git reset --hard &&
 	git apply --binary --index <current &&
-	tree1=`git write-tree` &&
+	tree1=$(git write-tree) &&
 	test "$tree1" = "$tree0"
 '
 
diff --git a/t/t4013-diff-various.sh b/t/t4013-diff-various.sh
index e77c09c..805b055 100755
--- a/t/t4013-diff-various.sh
+++ b/t/t4013-diff-various.sh
@@ -107,14 +107,14 @@ test_expect_success setup '
 +*++ [initial] Initial
 EOF
 
-V=`git version | sed -e 's/^git version //' -e 's/\./\\./g'`
+V=$(git version | sed -e 's/^git version //' -e 's/\./\\./g')
 while read cmd
 do
 	case "$cmd" in
 	'' | '#'*) continue ;;
 	esac
-	test=`echo "$cmd" | sed -e 's|[/ ][/ ]*|_|g'`
-	pfx=`printf "%04d" $test_count`
+	test=$(echo "$cmd" | sed -e 's|[/ ][/ ]*|_|g')
+	pfx=$(printf "%04d" $test_count)
 	expect="$TEST_DIRECTORY/t4013/diff.$test"
 	actual="$pfx-diff.$test"
 
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index 9c80633..282bee4 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -43,7 +43,7 @@ test_expect_success setup '
 test_expect_success "format-patch --ignore-if-in-upstream" '
 
 	git format-patch --stdout master..side >patch0 &&
-	cnt=`grep "^From " patch0 | wc -l` &&
+	cnt=$(grep "^From " patch0 | wc -l) &&
 	test $cnt = 3
 
 '
@@ -52,7 +52,7 @@ test_expect_success "format-patch --ignore-if-in-upstream" '
 
 	git format-patch --stdout \
 		--ignore-if-in-upstream master..side >patch1 &&
-	cnt=`grep "^From " patch1 | wc -l` &&
+	cnt=$(grep "^From " patch1 | wc -l) &&
 	test $cnt = 2
 
 '
@@ -69,7 +69,7 @@ test_expect_success "format-patch doesn't consider merge commits" '
 	git checkout -b merger master &&
 	test_tick &&
 	git merge --no-ff slave &&
-	cnt=`git format-patch -3 --stdout | grep "^From " | wc -l` &&
+	cnt=$(git format-patch -3 --stdout | grep "^From " | wc -l) &&
 	test $cnt = 3
 '
 
@@ -77,7 +77,7 @@ test_expect_success "format-patch result applies" '
 
 	git checkout -b rebuild-0 master &&
 	git am -3 patch0 &&
-	cnt=`git rev-list master.. | wc -l` &&
+	cnt=$(git rev-list master.. | wc -l) &&
 	test $cnt = 2
 '
 
@@ -85,7 +85,7 @@ test_expect_success "format-patch --ignore-if-in-upstream result applies" '
 
 	git checkout -b rebuild-1 master &&
 	git am -3 patch1 &&
-	cnt=`git rev-list master.. | wc -l` &&
+	cnt=$(git rev-list master.. | wc -l) &&
 	test $cnt = 2
 '
 
diff --git a/t/t4036-format-patch-signer-mime.sh b/t/t4036-format-patch-signer-mime.sh
index ba43f18..98d9713 100755
--- a/t/t4036-format-patch-signer-mime.sh
+++ b/t/t4036-format-patch-signer-mime.sh
@@ -42,7 +42,7 @@ test_expect_success 'attach and signoff do not duplicate mime headers' '
 
 	GIT_COMMITTER_NAME="はまの ふにおう" \
 	git format-patch -s --stdout -1 --attach >output &&
-	test `grep -ci ^MIME-Version: output` = 1
+	test $(grep -ci ^MIME-Version: output) = 1
 
 '
 
diff --git a/t/t4038-diff-combined.sh b/t/t4038-diff-combined.sh
index 1019d7b..41913c3 100755
--- a/t/t4038-diff-combined.sh
+++ b/t/t4038-diff-combined.sh
@@ -94,7 +94,7 @@ test_expect_success 'setup for --cc --raw' '
 	blob=$(echo file | git hash-object --stdin -w) &&
 	base_tree=$(echo "100644 blob $blob	file" | git mktree) &&
 	trees= &&
-	for i in `test_seq 1 40`
+	for i in $(test_seq 1 40)
 	do
 		blob=$(echo file$i | git hash-object --stdin -w) &&
 		trees="$trees$(echo "100644 blob $blob	file" | git mktree)$LF"
diff --git a/t/t4057-diff-combined-paths.sh b/t/t4057-diff-combined-paths.sh
index 097e632..dff36b7 100755
--- a/t/t4057-diff-combined-paths.sh
+++ b/t/t4057-diff-combined-paths.sh
@@ -5,7 +5,7 @@ test_description='combined diff show only paths that are different to all parent
 . ./test-lib.sh
 
 # verify that diffc.expect matches output of
-# `git diff -c --name-only HEAD HEAD^ HEAD^2`
+# $(git diff -c --name-only HEAD HEAD^ HEAD^2)
 diffc_verify () {
 	git diff -c --name-only HEAD HEAD^ HEAD^2 >diffc.actual &&
 	test_cmp diffc.expect diffc.actual
diff --git a/t/t4116-apply-reverse.sh b/t/t4116-apply-reverse.sh
index 1e4d438..ce8567f 100755
--- a/t/t4116-apply-reverse.sh
+++ b/t/t4116-apply-reverse.sh
@@ -30,10 +30,10 @@ test_expect_success setup '
 
 test_expect_success 'apply in forward' '
 
-	T0=`git rev-parse "second^{tree}"` &&
+	T0=$(git rev-parse "second^{tree}") &&
 	git reset --hard initial &&
 	git apply --index --binary patch &&
-	T1=`git write-tree` &&
+	T1=$(git write-tree) &&
 	test "$T0" = "$T1"
 '
 
@@ -62,22 +62,22 @@ test_expect_success 'setup separate repository lacking postimage' '
 
 test_expect_success 'apply in forward without postimage' '
 
-	T0=`git rev-parse "second^{tree}"` &&
+	T0=$(git rev-parse "second^{tree}") &&
 	(
 		cd initial &&
 		git apply --index --binary ../patch &&
-		T1=`git write-tree` &&
+		T1=$(git write-tree) &&
 		test "$T0" = "$T1"
 	)
 '
 
 test_expect_success 'apply in reverse without postimage' '
 
-	T0=`git rev-parse "initial^{tree}"` &&
+	T0=$(git rev-parse "initial^{tree}") &&
 	(
 		cd second &&
 		git apply --index --binary --reverse ../patch &&
-		T1=`git write-tree` &&
+		T1=$(git write-tree) &&
 		test "$T0" = "$T1"
 	)
 '
diff --git a/t/t4119-apply-config.sh b/t/t4119-apply-config.sh
index 3d0384d..c393be6 100755
--- a/t/t4119-apply-config.sh
+++ b/t/t4119-apply-config.sh
@@ -68,7 +68,7 @@ test_expect_success 'apply --whitespace=strip from config' '
 	check_result sub/file1
 '
 
-D=`pwd`
+D=$(pwd)
 
 test_expect_success 'apply --whitespace=strip in subdir' '
 
diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh
index d2c930d..7940f6f 100755
--- a/t/t4204-patch-id.sh
+++ b/t/t4204-patch-id.sh
@@ -45,8 +45,8 @@ test_expect_success 'patch-id supports git-format-patch output' '
 	git checkout same &&
 	git format-patch -1 --stdout | calc_patch_id same &&
 	test_cmp patch-id_master patch-id_same &&
-	set `git format-patch -1 --stdout | git patch-id` &&
-	test "$2" = `git rev-parse HEAD`
+	set $(git format-patch -1 --stdout | git patch-id) &&
+	test "$2" = $(git rev-parse HEAD)
 '
 
 test_expect_success 'whitespace is irrelevant in footer' '
diff --git a/t/t5000-tar-tree.sh b/t/t5000-tar-tree.sh
index 1cf0a4e..74fc5a8 100755
--- a/t/t5000-tar-tree.sh
+++ b/t/t5000-tar-tree.sh
@@ -123,7 +123,7 @@ test_expect_success \
     'add files to repository' \
     'find a -type f | xargs git update-index --add &&
      find a -type l | xargs git update-index --add &&
-     treeid=`git write-tree` &&
+     treeid=$(git write-tree) &&
      echo $treeid >treeid &&
      git update-ref HEAD $(TZ=GMT GIT_COMMITTER_DATE="2005-05-27 22:00:00" \
      git commit-tree $treeid </dev/null)'
@@ -207,7 +207,7 @@ test_expect_success \
 
 test_expect_success 'clients cannot access unreachable commits' '
 	test_commit unreachable &&
-	sha1=`git rev-parse HEAD` &&
+	sha1=$(git rev-parse HEAD) &&
 	git reset --hard HEAD^ &&
 	git archive $sha1 >remote.tar &&
 	test_must_fail git archive --remote=. $sha1 >remote.tar
@@ -215,7 +215,7 @@ test_expect_success 'clients cannot access unreachable commits' '
 
 test_expect_success 'upload-archive can allow unreachable commits' '
 	test_commit unreachable1 &&
-	sha1=`git rev-parse HEAD` &&
+	sha1=$(git rev-parse HEAD) &&
 	git reset --hard HEAD^ &&
 	git archive $sha1 >remote.tar &&
 	test_config uploadarchive.allowUnreachable true &&