Code-migrator NPM

code-migrator

This library help to create code migration tool.

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This library help to create migration tool for your library/framework/tool.

This library aim to provide command line interface for migration
This library help to run migration scripts
This library does not provide migration scripts
- You have to write migration script
- You choose codemod tool by own
- Your migration script must not depended on this library

codemod tools

You have to write migration scripts using following codemod tools.

code-migrator is a launcher library for the above tools.

Install

Install with npm:

npm install code-migrator

Requirements

Your library/framework/tool should follow Semantic Versioning
You have to prepare migration scripts

Usage

Define `MigrationList`

module.exports = {
    scripts: [
        {
            name: "use-strict",
            // absolute path for codemod scripts
            filePath: require.resolve("./scripts/use-strict")
        }
    ],
    versions: [
        // 0.x.x -> 1.0.0 apply "use-strict"
        {
            version: "1.0.0",
            scripts: ["use-strict"]
        },
        // 1.0.0 -> 2.0.0 does not apply anything
        {
            version: "2.0.0",
            scripts: []
        },
        {
            version: "3.0.0",
            scripts: []
        }
    ]
};

Example:

const { CodeMigrator } = require("code-migrator");
const meow = require("meow");

const cli = meow(
    `
    Usage
      $ code-migration-example <input>

    Options:
      --dry-run Enable dry run mode

    Examples
      $ code-migration-example "src/**/*.js"
`,
    {
        flags: {
            dryRun: {
                type: "boolean"
            }
        }
    }
);

const migrator = new CodeMigrator({
    moduleName: "test-module", // <= target npm module name if needed
    migrationList: require("../migrations"), // load migration list
    binCreator: ({ script, filePathList }) => {
        // migration script is executed by jscodeshift
        const binArgs = cli.flags.dryRun ? ["--dry"] : [];
        return {
            binPath: require.resolve(".bin/jscodeshift"),
            binArgs: binArgs.concat(["-t", script.filePath]).concat(filePathList)
        };
    }
});
migrator
    .run({
        filePatterns: cli.input
    })
    .then(() => {
        console.log("Done");
    })
    .catch(error => {
        console.error(error);
    });

For more details, see examples/

How to write unit test?

Code Migrator use Inquirer.js for building interactive interface. It is useful, but it is difficult to test.

You can run Code Migrator with non-interactive mode.

`run(options: CodeMigratorRunOption)`

If you set all defaultValue option, you can run code without interactive prompt.

const migrationList: MigrationList = require("./fixtures/scripts/migrations.js");
const codeMigrator = new CodeMigrator({
    migrationList: migrationList,
    moduleName: "test",
    binCreator: ({ script, filePathList }) => {
        return {
            binPath: require.resolve(".bin/jscodeshift"),
            binArgs: ["--dry", "-t", script.filePath].concat(filePathList)
        };
    }
});
codeMigrator
    .run({
        force: true,
        defaultValue: {
            currentVersion: "0.1.0",
            nextVersion: "3.0.0",
            files: [path.join(__dirname, "fixtures/scripts/src/**/*.js")]
        }
    });

`runScripts(options: RunScriptsOptions)`

runScripts is non-interactive mode by default.

const migrationList: MigrationList = require("./fixtures/scripts/migrations.js");
const codeMigrator = new CodeMigrator({
    migrationList: migrationList,
    moduleName: "test",
    binCreator: ({ script, filePathList }) => {
        return {
            binPath: require.resolve(".bin/jscodeshift"),
            binArgs: ["--dry", "-t", script.filePath].concat(filePathList)
        };
    }
});
codeMigrator.runScripts({
    force: true,
    scripts: migrationList.scripts,
    files: [path.join(__dirname, "/fixtures/scripts/src/**/*.js")]
});