Fix Shellcheck SC2006: Use $(...) notation

Use $(...) notation instead of legacy backticked `...`.

https://github.com/koalaman/shellcheck/wiki/SC2006

Signed-off-by: Dan Callahan <danc@element.io>

5 files changed, 6 insertions, 6 deletions

diff --git a/scripts-dev/check-newsfragment b/scripts-dev/check-newsfragment
index 5fc68e3213..af4de345df 100755
--- a/scripts-dev/check-newsfragment
+++ b/scripts-dev/check-newsfragment
@@ -42,9 +42,9 @@ echo "--------------------------"
 echo
 
 matched=0
-for f in `git diff --name-only FETCH_HEAD... -- changelog.d`; do
+for f in $(git diff --name-only FETCH_HEAD... -- changelog.d); do
     # check that any modified newsfiles on this branch end with a full stop.
-    lastchar=`tr -d '\n' < "$f" | tail -c 1`
+    lastchar=$(tr -d '\n' < "$f" | tail -c 1)
     if [ "$lastchar" != '.' ] && [ "$lastchar" != '!' ]; then
         echo -e "\e[31mERROR: newsfragment $f does not end with a '.' or '!'\e[39m" >&2
         echo -e "$CONTRIBUTING_GUIDE_TEXT" >&2
diff --git a/scripts-dev/check_line_terminators.sh b/scripts-dev/check_line_terminators.sh
index b48fb88b07..fffa24e01e 100755
--- a/scripts-dev/check_line_terminators.sh
+++ b/scripts-dev/check_line_terminators.sh
@@ -25,7 +25,7 @@
 # terminators are found, 0 otherwise.
 
 # cd to the root of the repository
-cd "`dirname "$0"`/.." || exit
+cd "$(dirname "$0")/.." || exit
 
 # Find and print files with non-unix line terminators
 if find . -path './.git/*' -prune -o -type f -print0 | xargs -0 grep -I -l $'\r$'; then
diff --git a/scripts-dev/config-lint.sh b/scripts-dev/config-lint.sh
index 7fb6ab68ef..6ce030b819 100755
--- a/scripts-dev/config-lint.sh
+++ b/scripts-dev/config-lint.sh
@@ -3,7 +3,7 @@
 # Exits with 0 if there are no problems, or another code otherwise.
 
 # cd to the root of the repository
-cd "`dirname "$0"`/.." || exit
+cd "$(dirname "$0")/.." || exit
 
 # Restore backup of sample config upon script exit
 trap "mv docs/sample_config.yaml.bak docs/sample_config.yaml" EXIT
diff --git a/scripts-dev/generate_sample_config b/scripts-dev/generate_sample_config
index 69d0b632df..4cd1d1d5b8 100755
--- a/scripts-dev/generate_sample_config
+++ b/scripts-dev/generate_sample_config
@@ -4,7 +4,7 @@
 
 set -e
 
-cd "`dirname "$0"`/.."
+cd "$(dirname "$0")/.."
 
 SAMPLE_CONFIG="docs/sample_config.yaml"
 SAMPLE_LOG_CONFIG="docs/sample_log_config.yaml"
diff --git a/scripts-dev/next_github_number.sh b/scripts-dev/next_github_number.sh
index 00e9b14569..5ecd515127 100755
--- a/scripts-dev/next_github_number.sh
+++ b/scripts-dev/next_github_number.sh
@@ -4,6 +4,6 @@ set -e
 
 # Fetch the current GitHub issue number, add one to it -- presto! The likely
 # next PR number.
-CURRENT_NUMBER=`curl -s "https://api.github.com/repos/matrix-org/synapse/issues?state=all&per_page=1" | jq -r ".[0].number"`
+CURRENT_NUMBER=$(curl -s "https://api.github.com/repos/matrix-org/synapse/issues?state=all&per_page=1" | jq -r ".[0].number")
 CURRENT_NUMBER=$((CURRENT_NUMBER+1))
 echo $CURRENT_NUMBER