diff --git a/.gitlab/ci/test.gitlab-ci.yml b/.gitlab/ci/test.gitlab-ci.yml
index a4ec77ee8..308701475 100644
--- a/.gitlab/ci/test.gitlab-ci.yml
+++ b/.gitlab/ci/test.gitlab-ci.yml
@@ -53,6 +53,12 @@ root-tests:
   script:
     - python3 -m pytest tests
 
+test-helpers:
+  extends: .test-stage
+  script:
+    - cd tests
+    - bash test_helpers.sh
+
 test-apps:
   extends: .test-stage
   script:
diff --git a/data/helpers.d/utils b/data/helpers.d/utils
index 942f6b34d..e651a5f77 100644
--- a/data/helpers.d/utils
+++ b/data/helpers.d/utils
@@ -217,11 +217,13 @@ ynh_setup_source () {
     fi
 
     # Apply patches
-    if (( $(find $YNH_APP_BASEDIR/sources/patches/ -type f -name "${source_id}-*.patch" 2> /dev/null | wc --lines) > "0" ))
+    local patches_folder=$(realpath $YNH_APP_BASEDIR/sources/patches/)
+    if (( $(find $patches_folder -type f -name "${source_id}-*.patch" 2> /dev/null | wc --lines) > "0" ))
     then
         (cd "$dest_dir"
-        for p in $YNH_APP_BASEDIR/sources/patches/${source_id}-*.patch
+        for p in $patches_folder/${source_id}-*.patch
         do
+            echo $p
             patch --strip=1 < $p
         done) || ynh_die --message="Unable to apply patches"
     fi
diff --git a/tests/test_helpers.d/ynhtest_setup_source.sh b/tests/test_helpers.d/ynhtest_setup_source.sh
new file mode 100644
index 000000000..69edf8ac9
--- /dev/null
+++ b/tests/test_helpers.d/ynhtest_setup_source.sh
@@ -0,0 +1,81 @@
+_make_dummy_src() {
+echo "test coucou"
+    if [ ! -e $HTTPSERVER_DIR/dummy.tar.gz ]
+    then
+        pushd "$HTTPSERVER_DIR"
+            mkdir dummy
+            pushd dummy
+            echo "Lorem Ipsum" > index.html
+            echo '{"foo": "bar"}' > conf.json
+            mkdir assets
+            echo '.some.css { }' > assets/main.css
+            echo 'var some="js";' > assets/main.js
+            popd
+            tar -czf dummy.tar.gz dummy
+        popd
+    fi
+    echo "SOURCE_URL=http://127.0.0.1:$HTTPSERVER_PORT/dummy.tar.gz"
+    echo "SOURCE_SUM=$(sha256sum $HTTPSERVER_DIR/dummy.tar.gz | awk '{print $1}')"
+}
+
+ynhtest_setup_source_nominal() {
+    final_path="$(mktemp -d -p $VAR_WWW)"
+    _make_dummy_src > ../conf/dummy.src
+    
+    ynh_setup_source --dest_dir="$final_path" --source_id="dummy"
+
+    test -e "$final_path"
+    test -e "$final_path/index.html"
+}
+
+ynhtest_setup_source_nominal_upgrade() {
+    final_path="$(mktemp -d -p $VAR_WWW)"
+    _make_dummy_src > ../conf/dummy.src
+
+    ynh_setup_source --dest_dir="$final_path" --source_id="dummy"
+
+    test "$(cat $final_path/index.html)" == "Lorem Ipsum"
+    
+    # Except index.html to get overwritten during next ynh_setup_source
+    echo "IEditedYou!" > $final_path/index.html
+    test "$(cat $final_path/index.html)" == "IEditedYou!"
+
+    ynh_setup_source --dest_dir="$final_path" --source_id="dummy"
+
+    test "$(cat $final_path/index.html)" == "Lorem Ipsum"
+}
+
+
+ynhtest_setup_source_with_keep() {
+    final_path="$(mktemp -d -p $VAR_WWW)"
+    _make_dummy_src > ../conf/dummy.src
+
+    echo "IEditedYou!" > $final_path/index.html
+    echo "IEditedYou!" > $final_path/test.txt
+
+    ynh_setup_source --dest_dir="$final_path" --source_id="dummy" --keep="index.html test.txt"
+
+    test -e "$final_path"
+    test -e "$final_path/index.html"
+    test -e "$final_path/test.txt"
+    test "$(cat $final_path/index.html)" == "IEditedYou!"
+    test "$(cat $final_path/test.txt)" == "IEditedYou!"
+}
+
+ynhtest_setup_source_with_patch() {
+    final_path="$(mktemp -d -p $VAR_WWW)"
+    _make_dummy_src > ../conf/dummy.src
+
+    mkdir -p ../sources/patches
+    cat > ../sources/patches/dummy-index.html.patch << EOF
+--- a/index.html
++++ b/index.html
+@@ -1 +1,1 @@
+-Lorem Ipsum
++Lorem Ipsum dolor sit amet
+EOF
+
+    ynh_setup_source --dest_dir="$final_path" --source_id="dummy"
+
+    test "$(cat $final_path/index.html)" == "Lorem Ipsum dolor sit amet"
+}
diff --git a/tests/test_helpers.sh b/tests/test_helpers.sh
new file mode 100644
index 000000000..6a5f29bf1
--- /dev/null
+++ b/tests/test_helpers.sh
@@ -0,0 +1,78 @@
+#!/bin/bash
+
+readonly NORMAL=$(printf '\033[0m')
+readonly BOLD=$(printf '\033[1m')
+readonly RED=$(printf '\033[31m')
+readonly GREEN=$(printf '\033[32m')
+readonly ORANGE=$(printf '\033[33m')
+
+function log_test()
+{
+    echo -n "${BOLD}$1${NORMAL} ... "
+}
+
+function log_passed()
+{
+    echo "${BOLD}${GREEN}✔ Passed${NORMAL}"
+}
+
+function log_failed()
+{
+    echo "${BOLD}${RED}✘ Failed${NORMAL}"
+}
+
+function cleanup()
+{
+    [ -n "$HTTPSERVER" ] && kill "$HTTPSERVER"
+    [ -d "$HTTPSERVER_DIR" ] && rm -rf "$HTTPSERVER_DIR"
+    [ -d "$VAR_WWW" ] && rm -rf "$VAR_WWW"
+}
+trap cleanup EXIT SIGINT
+
+# =========================================================
+
+# Dummy http server, to serve archives for ynh_setup_source
+HTTPSERVER_DIR=$(mktemp -d)
+HTTPSERVER_PORT=1312
+pushd "$HTTPSERVER_DIR" >/dev/null
+python -m SimpleHTTPServer $HTTPSERVER_PORT &>/dev/null &
+HTTPSERVER="$!"
+popd >/dev/null
+
+VAR_WWW=$(mktemp -d)/var/www
+mkdir -p $VAR_WWW
+# =========================================================
+
+source /usr/share/yunohost/helpers
+for TEST_SUITE in $(ls test_helpers.d/*)
+do
+    source $TEST_SUITE
+done
+
+# Hack to list all known function, keep only those starting by ynhtest_
+TESTS=$(declare -F | grep ' ynhtest_' | awk '{print $3}')
+
+global_result=0
+
+for TEST in $TESTS
+do
+    log_test $TEST
+    cd $(mktemp -d)
+    (app=ynhtest
+     YNH_APP_ID=$app
+     mkdir conf
+     mkdir scripts
+     cd scripts
+     set -eux
+     $TEST
+    ) > ./test.log 2>&1
+
+    if [[ $? == 0 ]]
+    then
+        set +x; log_passed;
+    else
+        set +x; echo -e "\n----------"; cat ./test.log; echo -e "----------"; log_failed; global_result=1;
+    fi
+done
+
+exit $global_result