From 7dc4e17401574624472e18c6ca74b6d33868c81e Mon Sep 17 00:00:00 2001
From: ChristophShyper <45788587+ChristophShyper@users.noreply.github.com>
Date: Fri, 15 May 2026 18:48:44 +0200
Subject: [PATCH 1/3] feat: enhance entrypoint script with git log and diff
 functionalities

---
 .dockerignore                            |   2 +
 Dockerfile                               |   3 +-
 entrypoint.sh                            | 153 ++++++++++++++++++-----
 scripts/replace-template-diff.sh         | 111 ++++++++++++++++
 tests/unit/test_branch_validation.sh     |  93 ++++++++++++++
 tests/unit/test_replace_template_diff.sh | 128 +++++++++++++++++++
 6 files changed, 459 insertions(+), 31 deletions(-)
 create mode 100755 scripts/replace-template-diff.sh
 create mode 100755 tests/unit/test_branch_validation.sh
 create mode 100755 tests/unit/test_replace_template_diff.sh

diff --git a/.dockerignore b/.dockerignore
index 215e08c..b05b20f 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -4,5 +4,7 @@
 # Include
 !Dockerfile
 !entrypoint.sh
+!scripts/
+!scripts/replace-template-diff.sh
 !LICENSE
 !README.md
diff --git a/Dockerfile b/Dockerfile
index 3a7eb3f..21e4565 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -5,11 +5,12 @@ ENV DEBIAN_FRONTEND=noninteractive
 
 # Copy all needed files
 COPY entrypoint.sh /
+COPY scripts/ /scripts/
 
 # Install needed packages
 SHELL ["/bin/bash", "-euxo", "pipefail", "-c"]
 # hadolint ignore=DL3008
-RUN chmod +x /entrypoint.sh ;\
+RUN chmod +x /entrypoint.sh /scripts/replace-template-diff.sh ;\
   apt-get update -y ;\
   apt-get install --no-install-recommends -y \
     curl \
diff --git a/entrypoint.sh b/entrypoint.sh
index 090bf07..3f086e5 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -4,6 +4,60 @@ set -Eeuo pipefail
 
 # Return code
 RET_CODE=0
+GIT_LOG=""
+GIT_SUMMARY=""
+GIT_DIFF=""
+SOURCE_COMPARE_REF=""
+TARGET_COMPARE_REF=""
+RESOLVED_BRANCH_REF=""
+
+REPLACE_TEMPLATE_SCRIPT="/scripts/replace-template-diff.sh"
+if [[ ! -x "${REPLACE_TEMPLATE_SCRIPT}" ]]; then
+  REPLACE_TEMPLATE_SCRIPT="$(dirname "$0")/scripts/replace-template-diff.sh"
+fi
+
+get_git_log() {
+  if [[ -z "${GIT_LOG}" ]]; then
+    echo -e "\nListing new commits in the source branch..."
+    git log --graph --pretty=format:'%Cred%h%Creset - %Cblue%an%Creset - %Cgreen%cd%Creset %n%s %b' --abbrev-commit --date=format:'%Y-%m-%d %H:%M:%S' "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}"
+    GIT_LOG=$(git log --graph --pretty=format:'%Cred%h%Creset - %Cblue%an%Creset - %Cgreen%cd%Creset %n%s%n%b' --abbrev-commit --date=format:'%Y-%m-%d %H:%M:%S' --no-color "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}")
+  fi
+}
+
+get_git_summary() {
+  if [[ -z "${GIT_SUMMARY}" ]]; then
+    echo -e "\n\nListing commits subjects in the source branch..."
+    git log --reverse --pretty=format:'%s' --abbrev-commit "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}"
+    GIT_SUMMARY=$(git log --reverse --pretty=format:'%s' --abbrev-commit "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}")
+  fi
+}
+
+get_git_diff() {
+  if [[ -z "${GIT_DIFF}" ]]; then
+    echo -e "\n\nListing files modified in the source branch..."
+    git diff --compact-summary "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}"
+    GIT_DIFF=$(git diff --compact-summary --no-color "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}")
+  fi
+}
+
+resolve_branch_ref() {
+  local branch_name="$1"
+  local remote_ref="refs/remotes/origin/${branch_name}"
+  local head_ref="refs/heads/${branch_name}"
+
+  if git show-ref --verify --quiet "${remote_ref}"; then
+    RESOLVED_BRANCH_REF="origin/${branch_name}"
+    return 0
+  fi
+
+  if git show-ref --verify --quiet "${head_ref}"; then
+    RESOLVED_BRANCH_REF="${branch_name}"
+    return 0
+  fi
+
+  echo -e "\n[ERROR] Missing branch reference: ${branch_name}" >&2
+  return 1
+}
 
 echo "Inputs:"
 echo "  source_branch: ${INPUT_SOURCE_BRANCH}"
@@ -60,41 +114,39 @@ echo "Target branch: ${TARGET_BRANCH}"
 echo -e "\nUpdating all branches..."
 git fetch origin '+refs/heads/*:refs/heads/*' --update-head-ok
 
+echo -e "\nValidating branches..."
+if ! resolve_branch_ref "${SOURCE_BRANCH}"; then
+  exit 1
+fi
+SOURCE_COMPARE_REF="${RESOLVED_BRANCH_REF}"
+
+if ! resolve_branch_ref "${TARGET_BRANCH}"; then
+  exit 1
+fi
+TARGET_COMPARE_REF="${RESOLVED_BRANCH_REF}"
+
 echo -e "\nComparing branches by revisions..."
-if [[ $(git rev-parse --revs-only "${SOURCE_BRANCH}") == $(git rev-parse --revs-only "${TARGET_BRANCH}") ]]; then
+if [[ $(git rev-parse --verify "${SOURCE_COMPARE_REF}") == $(git rev-parse --verify "${TARGET_COMPARE_REF}") ]]; then
   echo -e "\n[INFO] Both branches are the same. No action needed."
   exit 0
 fi
 
 echo -e "\nComparing branches by diff..."
-if [[ -z $(git diff "remotes/origin/${TARGET_BRANCH}...remotes/origin/${SOURCE_BRANCH}") ]]; then
+if git diff --quiet "${TARGET_COMPARE_REF}...${SOURCE_COMPARE_REF}"; then
   if [[ "${INPUT_ALLOW_NO_DIFF}" == "true" ]]; then
     echo -e "\n[INFO] Both branches are the same. Continuing."
   else
     echo -e "\n[INFO] Both branches are the same. No action needed."
     exit 0
   fi
+else
+  DIFF_STATUS="$?"
+  if [[ "${DIFF_STATUS}" != "1" ]]; then
+    echo -e "\n[ERROR] Failed to compare branches by diff (git exit code: ${DIFF_STATUS})."
+    exit 1
+  fi
 fi
 
-# sed has problems with putting multi-line strings in the next steps, and later we use # for sed
-# newline `\n` and hash `#` characters are replaced with some (hopefully) totally unlikely strings
-# after insertions of git information into template those strings are replaced back by proper characters
-
-echo -e "\nListing new commits in the source branch..."
-git log --graph --pretty=format:'%Cred%h%Creset - %Cblue%an%Creset - %Cgreen%cd%Creset %n%s %b' --abbrev-commit --date=format:'%Y-%m-%d %H:%M:%S' "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}"
-GIT_LOG=$(git log --graph --pretty=format:'%Cred%h%Creset - %Cblue%an%Creset - %Cgreen%cd%Creset %n%s%n%b' --abbrev-commit --date=format:'%Y-%m-%d %H:%M:%S' --no-color "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}")
-GIT_LOG=$(echo -e "${GIT_LOG}" | sed 's|#|^HaSz^|g' | sed ':a;N;$!ba; s/\n/^NowALiNiA^/g')
-
-echo -e "\n\nListing commits subjects in the source branch..."
-git log --reverse --pretty=format:'%s' --abbrev-commit "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}"
-GIT_SUMMARY=$(git log --reverse --pretty=format:'%s' --abbrev-commit "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}")
-GIT_SUMMARY=$(echo -e "${GIT_SUMMARY}" | sed 's|#|^HaSz^|g' | sed ':a;N;$!ba; s/\n/^NowALiNiA^/g')
-
-echo -e "\n\nListing files modified in the source branch..."
-git diff --compact-summary "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}"
-GIT_DIFF=$(git diff --compact-summary --no-color "origin/${TARGET_BRANCH}...origin/${SOURCE_BRANCH}")
-GIT_DIFF=$(echo -e "${GIT_DIFF}" | sed 's|#|^HaSz^|g' | sed ':a;N;$!ba; s/\n/^NowALiNiA^/g')
-
 echo -e "\nSetting template..."
 PR_NUMBER=$(hub pr list --base "${TARGET_BRANCH}" --head "${SOURCE_BRANCH}" --format '%I')
 if [[ -z "${PR_NUMBER}" ]]; then
@@ -103,6 +155,7 @@ if [[ -z "${PR_NUMBER}" ]]; then
   elif [[ -n "${INPUT_BODY}" ]]; then
     TEMPLATE="${INPUT_BODY}"
   else
+    get_git_log
     TEMPLATE="${GIT_LOG}"
   fi
 else
@@ -115,22 +168,62 @@ if [[ -n "${INPUT_OLD_STRING}" ]]; then
   if [[ -n "${INPUT_NEW_STRING}" ]]; then
     TEMPLATE=${TEMPLATE/${OLD_STRING}/${INPUT_NEW_STRING}}
   else
+    get_git_summary
     TEMPLATE=${TEMPLATE/${OLD_STRING}/${GIT_SUMMARY}}
   fi
 fi
 
 if [[ "${INPUT_GET_DIFF}" ==  "true" ]]; then
   echo -e "\nReplacing predefined fields with git information..."
-  # little hack to trick sed to work with multiline
-  # also backwards compatible with old replacement strings
-  TEMPLATE=$(echo -e "${TEMPLATE}" | sed ':a;N;$!ba; s#<!-- Diff summary - START -->.*<!-- Diff summary - END -->#<!-- Diff summary - START -->\n'"${GIT_SUMMARY}"'\n<!-- Diff summary - END -->#g')
-  TEMPLATE=$(echo -e "${TEMPLATE}" | sed ':a;N;$!ba; s#<!-- Diff commits -->#<!-- Diff commits - START -->\n'"${GIT_LOG}"'\n<!-- Diff commits - END -->#g')
-  TEMPLATE=$(echo -e "${TEMPLATE}" | sed ':a;N;$!ba; s#<!-- Diff commits - START -->.*<!-- Diff commits - END -->#<!-- Diff commits - START -->\n'"${GIT_LOG}"'\n<!-- Diff commits - END -->#g')
-  TEMPLATE=$(echo -e "${TEMPLATE}" | sed ':a;N;$!ba; s#<!-- Diff files -->#<!-- Diff files - START -->\n'"${GIT_DIFF}"'\n<!-- Diff files - END -->#g')
-  TEMPLATE=$(echo -e "${TEMPLATE}" | sed ':a;N;$!ba; s#<!-- Diff files - START -->.*<!-- Diff files - END -->#<!-- Diff files - START -->\n'"${GIT_DIFF}"'\n<!-- Diff files - END -->#g')
+  REPLACE_SUMMARY="false"
+  REPLACE_COMMITS="false"
+  REPLACE_FILES="false"
+
+  if [[ "${TEMPLATE}" == *"<!-- Diff summary - START -->"* && "${TEMPLATE}" == *"<!-- Diff summary - END -->"* ]]; then
+    REPLACE_SUMMARY="true"
+  fi
+  if [[ "${TEMPLATE}" == *"<!-- Diff commits -->"* || ( "${TEMPLATE}" == *"<!-- Diff commits - START -->"* && "${TEMPLATE}" == *"<!-- Diff commits - END -->"* ) ]]; then
+    REPLACE_COMMITS="true"
+  fi
+  if [[ "${TEMPLATE}" == *"<!-- Diff files -->"* || ( "${TEMPLATE}" == *"<!-- Diff files - START -->"* && "${TEMPLATE}" == *"<!-- Diff files - END -->"* ) ]]; then
+    REPLACE_FILES="true"
+  fi
+
+  if [[ "${REPLACE_SUMMARY}" == "true" || "${REPLACE_COMMITS}" == "true" || "${REPLACE_FILES}" == "true" ]]; then
+    TEMPLATE_WORK_FILE="/tmp/template-work.md"
+    SUMMARY_FILE="/tmp/template-summary.txt"
+    COMMITS_FILE="/tmp/template-commits.txt"
+    FILES_FILE="/tmp/template-files.txt"
+
+    printf '%s' "${TEMPLATE}" > "${TEMPLATE_WORK_FILE}"
+
+    if [[ "${REPLACE_SUMMARY}" == "true" ]]; then
+      get_git_summary
+      printf '%s' "${GIT_SUMMARY}" > "${SUMMARY_FILE}"
+    fi
+    if [[ "${REPLACE_COMMITS}" == "true" ]]; then
+      get_git_log
+      printf '%s' "${GIT_LOG}" > "${COMMITS_FILE}"
+    fi
+    if [[ "${REPLACE_FILES}" == "true" ]]; then
+      get_git_diff
+      printf '%s' "${GIT_DIFF}" > "${FILES_FILE}"
+    fi
+
+    "${REPLACE_TEMPLATE_SCRIPT}" \
+      --template "${TEMPLATE_WORK_FILE}" \
+      --summary-file "${SUMMARY_FILE}" \
+      --commits-file "${COMMITS_FILE}" \
+      --files-file "${FILES_FILE}" \
+      --replace-summary "${REPLACE_SUMMARY}" \
+      --replace-commits "${REPLACE_COMMITS}" \
+      --replace-files "${REPLACE_FILES}"
+
+    TEMPLATE=$(cat "${TEMPLATE_WORK_FILE}")
+  else
+    echo -e "[INFO] No diff markers found in template body. Skipping get_diff replacements."
+  fi
 fi
-#shellcheck disable=SC2016
-TEMPLATE=$(echo -e "${TEMPLATE}" | sed 's|\^HaSz\^|#|g' | sed '1h;2,$H;$!d;g; s|\^NowALiNiA\^|\n|g')
 
 if [[ -z "${PR_NUMBER}" ]]; then
   echo -e "\nSetting all arguments..."
diff --git a/scripts/replace-template-diff.sh b/scripts/replace-template-diff.sh
new file mode 100755
index 0000000..e63fca3
--- /dev/null
+++ b/scripts/replace-template-diff.sh
@@ -0,0 +1,111 @@
+#!/usr/bin/env bash
+
+set -Eeuo pipefail
+
+TEMPLATE_FILE=""
+SUMMARY_FILE=""
+COMMITS_FILE=""
+FILES_FILE=""
+REPLACE_SUMMARY="false"
+REPLACE_COMMITS="false"
+REPLACE_FILES="false"
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --template)
+      TEMPLATE_FILE="$2"
+      shift 2
+      ;;
+    --summary-file)
+      SUMMARY_FILE="$2"
+      shift 2
+      ;;
+    --commits-file)
+      COMMITS_FILE="$2"
+      shift 2
+      ;;
+    --files-file)
+      FILES_FILE="$2"
+      shift 2
+      ;;
+    --replace-summary)
+      REPLACE_SUMMARY="$2"
+      shift 2
+      ;;
+    --replace-commits)
+      REPLACE_COMMITS="$2"
+      shift 2
+      ;;
+    --replace-files)
+      REPLACE_FILES="$2"
+      shift 2
+      ;;
+    *)
+      echo "[ERROR] Unknown argument: $1" >&2
+      exit 1
+      ;;
+  esac
+done
+
+if [[ -z "$TEMPLATE_FILE" ]]; then
+  echo "[ERROR] Missing required argument: --template" >&2
+  exit 1
+fi
+
+if [[ ! -f "$TEMPLATE_FILE" ]]; then
+  echo "[ERROR] Template file does not exist: $TEMPLATE_FILE" >&2
+  exit 1
+fi
+
+if [[ "$REPLACE_SUMMARY" == "true" && ( -z "$SUMMARY_FILE" || ! -f "$SUMMARY_FILE" ) ]]; then
+  echo "[ERROR] Summary replacement requested but file is missing" >&2
+  exit 1
+fi
+
+if [[ "$REPLACE_COMMITS" == "true" && ( -z "$COMMITS_FILE" || ! -f "$COMMITS_FILE" ) ]]; then
+  echo "[ERROR] Commits replacement requested but file is missing" >&2
+  exit 1
+fi
+
+if [[ "$REPLACE_FILES" == "true" && ( -z "$FILES_FILE" || ! -f "$FILES_FILE" ) ]]; then
+  echo "[ERROR] Files replacement requested but file is missing" >&2
+  exit 1
+fi
+
+REPLACE_SUMMARY="$REPLACE_SUMMARY" \
+REPLACE_COMMITS="$REPLACE_COMMITS" \
+REPLACE_FILES="$REPLACE_FILES" \
+SUMMARY_FILE="$SUMMARY_FILE" \
+COMMITS_FILE="$COMMITS_FILE" \
+FILES_FILE="$FILES_FILE" \
+perl -0777 -i -pe '
+  BEGIN {
+    sub read_file {
+      my ($path) = @_;
+      return q{} if !defined($path) || $path eq q{};
+      open my $fh, q{<}, $path or die "Unable to read replacement file: $path\n";
+      local $/;
+      my $content = <$fh>;
+      close $fh;
+      return defined($content) ? $content : q{};
+    }
+
+    $summary = read_file($ENV{SUMMARY_FILE});
+    $commits = read_file($ENV{COMMITS_FILE});
+    $files = read_file($ENV{FILES_FILE});
+  }
+
+  if ($ENV{REPLACE_SUMMARY} eq q{true}) {
+    s{<!-- Diff summary - START -->.*?<!-- Diff summary - END -->}{"<!-- Diff summary - START -->\n$summary\n<!-- Diff summary - END -->"}gse;
+  }
+
+  if ($ENV{REPLACE_COMMITS} eq q{true}) {
+    s{<!-- Diff commits -->}{"<!-- Diff commits - START -->\n$commits\n<!-- Diff commits - END -->"}gse;
+    s{<!-- Diff commits - START -->.*?<!-- Diff commits - END -->}{"<!-- Diff commits - START -->\n$commits\n<!-- Diff commits - END -->"}gse;
+  }
+
+  if ($ENV{REPLACE_FILES} eq q{true}) {
+    s{<!-- Diff files -->}{"<!-- Diff files - START -->\n$files\n<!-- Diff files - END -->"}gse;
+    s{<!-- Diff files - START -->.*?<!-- Diff files - END -->}{"<!-- Diff files - START -->\n$files\n<!-- Diff files - END -->"}gse;
+  }
+' "$TEMPLATE_FILE"
diff --git a/tests/unit/test_branch_validation.sh b/tests/unit/test_branch_validation.sh
new file mode 100755
index 0000000..36def0e
--- /dev/null
+++ b/tests/unit/test_branch_validation.sh
@@ -0,0 +1,93 @@
+#!/usr/bin/env bash
+
+set -Eeuo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
+SCRIPT_PATH="${SCRIPT_DIR}/../../entrypoint.sh"
+TMP_DIR="$(mktemp -d)"
+trap 'rm -rf "${TMP_DIR}"' EXIT
+
+assert_contains() {
+  local file_path="$1"
+  local expected="$2"
+  if ! grep -Fq -- "${expected}" "${file_path}"; then
+    echo "Assertion failed. Expected to find: ${expected}" >&2
+    echo "----- FILE CONTENT -----" >&2
+    cat "${file_path}" >&2
+    exit 1
+  fi
+}
+
+git init --initial-branch=main "${TMP_DIR}/repo" >/dev/null
+
+mkdir -p "${TMP_DIR}/bin"
+cat > "${TMP_DIR}/bin/git" <<'EOF'
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+REAL_GIT="${REAL_GIT:-/usr/bin/git}"
+
+if [[ "$#" -ge 2 && "$1" == "remote" && "$2" == "set-url" ]]; then
+  exit 0
+fi
+
+if [[ "$#" -ge 1 && "$1" == "fetch" ]]; then
+  exec "${REAL_GIT}" fetch . '+refs/heads/*:refs/heads/*' --update-head-ok
+fi
+
+exec "${REAL_GIT}" "$@"
+EOF
+chmod +x "${TMP_DIR}/bin/git"
+
+pushd "${TMP_DIR}/repo" >/dev/null
+git config user.name "tester"
+git config user.email "tester@example.com"
+printf 'x\n' > README.md
+git add README.md
+git commit -m "init" >/dev/null
+git branch develop
+git update-ref refs/remotes/origin/develop refs/heads/develop
+git remote add origin .
+popd >/dev/null
+
+LOG_FILE="${TMP_DIR}/run.log"
+set +e
+(
+  cd "${TMP_DIR}/repo"
+  PATH="${TMP_DIR}/bin:${PATH}" \
+  REAL_GIT="$(command -v git)" \
+  GITHUB_ACTOR="ci-user" \
+  GITHUB_TOKEN="token" \
+  GITHUB_REPOSITORY="owner/repo" \
+  GITHUB_WORKSPACE="${TMP_DIR}/repo" \
+  GITHUB_OUTPUT="${TMP_DIR}/output.txt" \
+  INPUT_GITHUB_TOKEN="token" \
+  INPUT_SOURCE_BRANCH="develop" \
+  INPUT_TARGET_BRANCH="release/MAPL-v3" \
+  INPUT_TITLE="" \
+  INPUT_TEMPLATE="" \
+  INPUT_BODY="" \
+  INPUT_REVIEWER="" \
+  INPUT_ASSIGNEE="" \
+  INPUT_LABEL="" \
+  INPUT_MILESTONE="" \
+  INPUT_DRAFT="false" \
+  INPUT_GET_DIFF="false" \
+  INPUT_OLD_STRING="" \
+  INPUT_NEW_STRING="" \
+  INPUT_IGNORE_USERS="dependabot" \
+  INPUT_ALLOW_NO_DIFF="false" \
+  bash "${SCRIPT_PATH}" >"${LOG_FILE}" 2>&1
+)
+STATUS="$?"
+set -e
+
+if [[ "${STATUS}" == "0" ]]; then
+  echo "Expected non-zero exit code when target branch is missing" >&2
+  cat "${LOG_FILE}" >&2
+  exit 1
+fi
+
+assert_contains "${LOG_FILE}" "[ERROR] Missing branch reference: release/MAPL-v3"
+
+echo "Branch validation test passed."
diff --git a/tests/unit/test_replace_template_diff.sh b/tests/unit/test_replace_template_diff.sh
new file mode 100755
index 0000000..2ab535c
--- /dev/null
+++ b/tests/unit/test_replace_template_diff.sh
@@ -0,0 +1,128 @@
+#!/usr/bin/env bash
+
+set -Eeuo pipefail
+
+SCRIPT_PATH="$(dirname "$0")/../../scripts/replace-template-diff.sh"
+
+TMP_DIR="$(mktemp -d)"
+trap 'rm -rf "${TMP_DIR}"' EXIT
+
+assert_contains() {
+  local file_path="$1"
+  local expected="$2"
+  if ! grep -Fq -- "${expected}" "${file_path}"; then
+    echo "Assertion failed. Expected to find: ${expected}" >&2
+    echo "----- FILE CONTENT -----" >&2
+    cat "${file_path}" >&2
+    exit 1
+  fi
+}
+
+assert_not_contains() {
+  local file_path="$1"
+  local not_expected="$2"
+  if grep -Fq -- "${not_expected}" "${file_path}"; then
+    echo "Assertion failed. Did not expect to find: ${not_expected}" >&2
+    echo "----- FILE CONTENT -----" >&2
+    cat "${file_path}" >&2
+    exit 1
+  fi
+}
+
+run_replacement() {
+  local template_file="$1"
+  local replace_summary="$2"
+  local replace_commits="$3"
+  local replace_files="$4"
+
+  "${SCRIPT_PATH}" \
+    --template "${template_file}" \
+    --summary-file "${TMP_DIR}/summary.txt" \
+    --commits-file "${TMP_DIR}/commits.txt" \
+    --files-file "${TMP_DIR}/files.txt" \
+    --replace-summary "${replace_summary}" \
+    --replace-commits "${replace_commits}" \
+    --replace-files "${replace_files}"
+}
+
+cat > "${TMP_DIR}/summary.txt" <<'EOF'
+Summary line 1
+Summary line 2
+EOF
+
+cat > "${TMP_DIR}/commits.txt" <<'EOF'
+abc123 - commit one
+def456 - commit two
+EOF
+
+cat > "${TMP_DIR}/files.txt" <<'EOF'
+M README.md
+A scripts/new.sh
+EOF
+
+cat > "${TMP_DIR}/template-full.md" <<'EOF'
+Body start
+<!-- Diff summary - START -->
+old summary
+<!-- Diff summary - END -->
+<!-- Diff commits -->
+<!-- Diff files - START -->
+old files
+<!-- Diff files - END -->
+Body end
+EOF
+
+run_replacement "${TMP_DIR}/template-full.md" "true" "true" "true"
+
+assert_contains "${TMP_DIR}/template-full.md" "Summary line 1"
+assert_contains "${TMP_DIR}/template-full.md" "abc123 - commit one"
+assert_contains "${TMP_DIR}/template-full.md" "M README.md"
+assert_contains "${TMP_DIR}/template-full.md" "<!-- Diff commits - START -->"
+assert_contains "${TMP_DIR}/template-full.md" "<!-- Diff files - END -->"
+assert_not_contains "${TMP_DIR}/template-full.md" "old summary"
+assert_not_contains "${TMP_DIR}/template-full.md" "old files"
+
+cat > "${TMP_DIR}/template-commits-block.md" <<'EOF'
+Body start
+<!-- Diff commits - START -->
+legacy
+<!-- Diff commits - END -->
+Body end
+EOF
+
+run_replacement "${TMP_DIR}/template-commits-block.md" "false" "true" "false"
+
+assert_contains "${TMP_DIR}/template-commits-block.md" "def456 - commit two"
+assert_not_contains "${TMP_DIR}/template-commits-block.md" "legacy"
+
+cat > "${TMP_DIR}/template-no-markers.md" <<'EOF'
+No markers here.
+EOF
+
+run_replacement "${TMP_DIR}/template-no-markers.md" "false" "false" "false"
+
+assert_contains "${TMP_DIR}/template-no-markers.md" "No markers here."
+
+python3 - <<'PY' > "${TMP_DIR}/commits-large.txt"
+for i in range(15000):
+    print(f"{i:05d} - synthetic commit line with payload")
+PY
+
+cat > "${TMP_DIR}/template-large.md" <<'EOF'
+Large body start
+<!-- Diff commits -->
+Large body end
+EOF
+
+"${SCRIPT_PATH}" \
+  --template "${TMP_DIR}/template-large.md" \
+  --summary-file "${TMP_DIR}/summary.txt" \
+  --commits-file "${TMP_DIR}/commits-large.txt" \
+  --files-file "${TMP_DIR}/files.txt" \
+  --replace-summary "false" \
+  --replace-commits "true" \
+  --replace-files "false"
+
+assert_contains "${TMP_DIR}/template-large.md" "14999 - synthetic commit line with payload"
+
+echo "All replace-template-diff tests passed."

From 8f22cc75142bcc63fae227c4949f669c5a4d4797 Mon Sep 17 00:00:00 2001
From: ChristophShyper <45788587+ChristophShyper@users.noreply.github.com>
Date: Fri, 15 May 2026 19:28:40 +0200
Subject: [PATCH 2/3] temp hardcode Dockerfile

---
 action.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/action.yml b/action.yml
index 7462ed1..9347724 100644
--- a/action.yml
+++ b/action.yml
@@ -72,7 +72,7 @@ outputs:
     description: Pull request number
 runs:
   using: docker
-  image: docker://devopsinfra/action-pull-request:v1.0.2
+  image: Dockerfile
   env:
     GITHUB_TOKEN: ${{ inputs.github_token }}
 branding:

From bfe6826658c87cdcf619f1999c8d1716ce988d32 Mon Sep 17 00:00:00 2001
From: ChristophShyper <45788587+ChristophShyper@users.noreply.github.com>
Date: Fri, 15 May 2026 19:50:31 +0200
Subject: [PATCH 3/3] feat: enhance template replacement functionality with
 conditional file reading

---
 scripts/replace-template-diff.sh         |  6 +++---
 tests/unit/test_replace_template_diff.sh | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/scripts/replace-template-diff.sh b/scripts/replace-template-diff.sh
index e63fca3..49a83b5 100755
--- a/scripts/replace-template-diff.sh
+++ b/scripts/replace-template-diff.sh
@@ -90,9 +90,9 @@ perl -0777 -i -pe '
       return defined($content) ? $content : q{};
     }
 
-    $summary = read_file($ENV{SUMMARY_FILE});
-    $commits = read_file($ENV{COMMITS_FILE});
-    $files = read_file($ENV{FILES_FILE});
+    $summary = $ENV{REPLACE_SUMMARY} eq q{true} ? read_file($ENV{SUMMARY_FILE}) : q{};
+    $commits = $ENV{REPLACE_COMMITS} eq q{true} ? read_file($ENV{COMMITS_FILE}) : q{};
+    $files = $ENV{REPLACE_FILES} eq q{true} ? read_file($ENV{FILES_FILE}) : q{};
   }
 
   if ($ENV{REPLACE_SUMMARY} eq q{true}) {
diff --git a/tests/unit/test_replace_template_diff.sh b/tests/unit/test_replace_template_diff.sh
index 2ab535c..0284839 100755
--- a/tests/unit/test_replace_template_diff.sh
+++ b/tests/unit/test_replace_template_diff.sh
@@ -45,6 +45,17 @@ run_replacement() {
     --replace-files "${replace_files}"
 }
 
+run_replacement_files_only() {
+  local template_file="$1"
+
+  "${SCRIPT_PATH}" \
+    --template "${template_file}" \
+    --files-file "${TMP_DIR}/files.txt" \
+    --replace-summary "false" \
+    --replace-commits "false" \
+    --replace-files "true"
+}
+
 cat > "${TMP_DIR}/summary.txt" <<'EOF'
 Summary line 1
 Summary line 2
@@ -103,6 +114,19 @@ run_replacement "${TMP_DIR}/template-no-markers.md" "false" "false" "false"
 
 assert_contains "${TMP_DIR}/template-no-markers.md" "No markers here."
 
+cat > "${TMP_DIR}/template-files-only.md" <<'EOF'
+Body start
+<!-- Diff files - START -->
+old files
+<!-- Diff files - END -->
+Body end
+EOF
+
+run_replacement_files_only "${TMP_DIR}/template-files-only.md"
+
+assert_contains "${TMP_DIR}/template-files-only.md" "A scripts/new.sh"
+assert_not_contains "${TMP_DIR}/template-files-only.md" "old files"
+
 python3 - <<'PY' > "${TMP_DIR}/commits-large.txt"
 for i in range(15000):
     print(f"{i:05d} - synthetic commit line with payload")