feat(auto update): add utility function to upgrade package's version

Signed-off-by: Aditya Alok <dev.aditya.alok@gmail.com>

scripts/updates/utils/termux_pkg_upgrade_version.sh

@@ -0,0 +1,80 @@
+# shellcheck shell=bash
+termux_pkg_upgrade_version() {
+	if [[ "$#" -lt 1 ]]; then
+		# Show usage.
+		termux_error_exit <<-EndUsage
+			Usage: ${FUNCNAME[0]} LATEST_VERSION [--skip-version-check]
+			Version should be passed with epoch, if any.
+		EndUsage
+	fi
+
+	local LATEST_VERSION="$1"
+	local SKIP_VERSION_CHECK="${2:-}"
+	local PKG_DIR
+	PKG_DIR="${TERMUX_SCRIPTDIR}/packages/${TERMUX_PKG_NAME}"
+
+	if [[ "${SKIP_VERSION_CHECK}" != "--skip-version-check" ]]; then
+		if ! termux_pkg_is_update_needed \
+			"${TERMUX_PKG_VERSION}" "${LATEST_VERSION}" "${TERMUX_PKG_UPDATE_VERSION_REGEXP}"; then
+			echo "INFO: No update needed. Already at version '${TERMUX_PKG_VERSION}'."
+			return 0
+		fi
+	fi
+
+	if [[ "${BUILD_PACKAGES}" == "false" ]]; then
+		echo "INFO: package needs to be updated to $(echo "${LATEST_VERSION}" | cut -d':' -f2)."
+	else
+		echo "INFO: package being updated to $(echo "${LATEST_VERSION}" | cut -d':' -f2)."
+
+		sed -i \
+			"s/^\(TERMUX_PKG_VERSION=\)\(.*\)\$/\1${LATEST_VERSION}/g" \
+			"${PKG_DIR}/build.sh"
+		sed -i \
+			"/TERMUX_PKG_REVISION=/d" \
+			"${PKG_DIR}/build.sh"
+
+		# Update checksum
+		if [[ "${TERMUX_PKG_SHA256[*]}" != "SKIP_CHECKSUM" ]] && [[ "${TERMUX_PKG_SRCURL: -4}" != ".git" ]]; then
+			echo n | "${TERMUX_SCRIPTDIR}/scripts/bin/update-checksum" "${TERMUX_PKG_NAME}" || {
+				git checkout -- "${PKG_DIR}"
+				git pull --rebase
+				termux_error_exit "ERROR: failed to update checksum."
+			}
+		fi
+
+		echo "INFO: Trying to build package."
+		if "${TERMUX_SCRIPTDIR}/scripts/run-docker.sh" ./build-package.sh -a "${TERMUX_ARCH}" -I "${TERMUX_PKG_NAME}"; then
+			if [[ "${GIT_COMMIT_PACKAGES}" == "true" ]]; then
+				echo "INFO: Committing package."
+				stderr="$(
+					git add "${PKG_DIR}" 2>&1 >/dev/null
+					git commit -m "${TERMUX_PKG_NAME}: update to $(echo "${LATEST_VERSION}" | cut -d':' -f2)" \
+						-m "This commit has been automatically submitted by Github Actions." 2>&1 >/dev/null
+				)" || {
+					termux_error_exit <<-EndOfError
+						ERROR: git commit failed. See below for details.
+						${stderr}
+					EndOfError
+				}
+			fi
+
+			if [[ "${GIT_PUSH_PACKAGES}" == "true" ]]; then
+				echo "INFO: Pushing package."
+				stderr="$(
+					git status # DEBUG
+					git pull --rebase 2>&1 >/dev/null
+					git push 2>&1 >/dev/null
+				)" || {
+					termux_error_exit <<-EndOfError
+						ERROR: git push failed. See below for details.
+						${stderr}
+					EndOfError
+				}
+			fi
+		else
+			git checkout -- "${PKG_DIR}"
+			termux_error_exit "ERROR: failed to build."
+		fi
+
+	fi
+}