Simple pre commit git hook for updating a dart/flutter program version number and generating a constant for the application at runtime.

pre-commit

#!/bin/sh
npm run version-sync
git add pubspec.yaml
git add lib/src/version.dart

version.js

const fs = require('fs');
const path = require('path');
const yaml = require('js-yaml');

function getPubspecVersion(path, key) {
    const file = fs.readFileSync(path, 'utf8');
    const data = yaml.load(file);
    return data[key];
}

function setPubspecVersion(path, key, version) {
    const file = fs.readFileSync(path, 'utf8');
    const data = yaml.load(file);
    data[key] = version;
    const yamlString = yaml.dump(data);
    fs.writeFileSync(path, yamlString);
}

function updateGeneratedVersion(path, version) {
    const contents = [`// Generated code. Do not modify.`, `const packageVersion = '${version}';`];
    fs.writeFileSync(path, contents.join('\n'));
}

const version = getPubspecVersion(path.join(__dirname, '../pubspec.yaml'), 'version');
console.log(`Version: ${version}`);
const parts = version.split('+');
const versionName = parts[0];
const versionBuild = parseInt(parts[1]) || 0;
const newVersion = `${versionName}+${versionBuild + 1}`;

updateGeneratedVersion(path.join(__dirname, '../lib/src/version.dart'), newVersion);
setPubspecVersion(path.join(__dirname, '../pubspec.yaml'), 'version', newVersion);