🦕 Molt

Warning

Molt is still under active development. The API is not stable yet and may change frequently.

Molt is a Deno module to bump version strings in import specifiers, like udd, but with different design principles:

The Deno way - Molt finds dependencies and checks their latest versions in a consistent way as the Deno runtime, with deno_graph and import_map crates, etc.

Module-first - The core logic is provided as a Deno module, which enables you to write the best scripts for your use cases.

Git-friendly - The operations can be easily divided into logical groups for subsequent git commits.

Features

Molt can check updates to dependencies written in different formats and bump their versions. URL imports, npm: and jsr: specifiers are all supported:

Important

Molt does NOT bump version ranges like 1, 1.x, ~1.2.3 and ^1.2.3 in npm: and jrs: specifiers, but only updates a lockfile.

Import specifiers in ES modules

- import { assert } from "https://deno.land/std@0.200.0/assert/mod.ts";
+ import { assert } from "https://deno.land/std@0.218.2/assert/mod.ts";
...

Import maps

  {
    "imports": {
      "@core/match": "jsr:@core/match@0.1.x",
-     "@std/assert": "jsr:@std/assert@0.200.0",
-     "node-emoji": "npm:node-emoji@2.0.0"
+     "@std/assert": "jsr:@std/assert@0.218.2",
+     "node-emoji": "npm:node-emoji@2.1.3"
    }
  }

Lock files

Warning

This is still an experimental feature and may not work as expected. Requires Deno v1.41.0 or later.

  {
    "version": "3",
    "packages": {
      "specifiers": {
-       "jsr:@core/match@0.1.x": "jsr:@core/match@0.1.0",
+       "jsr:@core/match@0.1.x": "jsr:@core/match@0.1.9",
        "npm:ts-toolbelt@9.6.0": "npm:ts-toolbelt@9.6.0"
      },
      "jsr": {
-       "@core/match@0.1.0": {
-         "integrity": "6f1edfca5215735a12aa2dbd920ead331a501eb5e3ad70cba3b9787610c7bfaf",
+       "@core/match@0.1.9": {
+         "integrity": "ceff06cf40212bb720925972a4405bef373efe768690b344ac4fd7ca7189f746",
          "dependencies": [
            "npm:ts-toolbelt@9.6.0"
        ...

Usage

@molt/core

API Reference

Examples

Update all dependencies in a module and write the changes to local files

import { collect, write } from "jsr:@molt/core";

const updates = await collect("./mod.ts");
await write(updates);

Update all dependencies in a module and commit the changes to git

import { collect, commit } from "jsr:@molt/core";

const updates = await collect("./mod.ts");

await commit(updates, {
  groupBy: (dependency) => dependency.name,
  composeCommitMessage: ({ group, version }) =>
    `build(deps): bump ${group} to ${version!.to}`,
});

@molt/cli

Although it is encouraged to write your own scripts, a pre-built CLI tool is also provided for convenience or as a reference implementation, which is supposed to cover most of the use cases.

Installation (optional)

The molt CLI can be installed globally with the following command, for example:

deno install --global --allow-env --allow-read --allow-write --allow-net --allow-run=git,deno\
--name molt jsr:@molt/cli

Alternatively, you may prefer to run the remote script directly through deno task for better security or reproducibility:

{
  "tasks": {
    "update": "deno run --allow-env --allow-read --allow-write=. --allow-run=git,deno --allow-net=jsr.io,registry.npmjs.org jsr:@molt/cli ./*.ts",
    "update:commit": "deno task -q update --commit --pre-commit=fmt,lint"
  }
}

Usage

> molt --help
Usage: molt <modules...>

Description:

  Check updates to dependencies in Deno modules and configuration files

Options:

  -h, --help                       - Show this help.                                                                         
  -v, --version                    - Print version info                                                                      
  -w, --write                      - Write changes to local files                        (Conflicts: --commit)               
  -c, --commit                     - Commit changes to local git repository              (Conflicts: --write)                
  --changelog      [commit_types]  - Show a curated changelog for each update                                                
  --debug                          - Print debug information                                                                 
  --import-map     <file>          - Specify import map file                                                                 
  --ignore         <deps>          - Ignore dependencies                                                                     
  --no-resolve                     - Do not resolve local imports                                                         
  --only           <deps>          - Check specified dependencies                                                            
  --pre-commit     <tasks>         - Run tasks before each commit                        (Depends: --commit)                 
  --prefix         <prefix>        - Prefix for commit messages                          (Depends: --commit)                 
  --prefix-lock    <prefix>        - Prefix for commit messages of updating a lock file  (Depends: --commit, --unstable-lock)
  --unstable-lock  [file]          - Enable unstable updating of a lock file

Note

Molt CLI automatically finds deno.json or deno.jsonc in the current working directory or its parent directories and uses import maps defined in the file if available.

Examples

Check for updates

> molt deno.json
📦 @luca/flag 1.0.0 => 1.1.0
📦 deno.land/std 0.200.0 => 0.218.2
📦 deno.land/x/deno_graph 0.50.0 => 0.69.7
📦 node-emoji 2.0.0 => 2.1.3

You may specify the modules to check, alternatively:

> molt main.ts main_test.ts
    ...

Write changes to files

> molt deno.json --write
    ...
💾 deno.json

Commit changes to git

> molt deno.json --commit --prefix :package:
    ...
📝 :package: bump @luca/flag from 1.0.0 to 1.1.0
📝 :package: bump deno.land/std from 0.200.0 to 0.218.2
📝 :package: bump deno.land/x/deno_graph from 0.50.0 to 0.69.7
📝 :package: bump node-emoji from 2.0.0 to 2.1.3

Compatibility with registries

We check compatibility with various registries in an integration test.

Deno's official registries

Molt offers first-class support for the following registries, which means that we may implement registry-specific routines for them:

• deno.land/std
• deno.land/x
• jsr (via jsr: specifier)
• npm (via npm: specifier)

Third-party registries

Molt also works with the following third-party registries:

• esm.sh
• unpkg.com

The following registries are not compatible with Molt:

• cdn.jsdelivr.net
• cdn.skypack.dev
• esm.run
• denopkg.com
• ga.jspm.io
• pax.deno.dev
• raw.githubusercontent.com
• x.nest.land

How it works

TBW

Limitations

The following limitations are imposed by the design of Molt:

• Version constraints on URL imports are not supported.
• Dependencies in import specifiers are only targeted.

See issues for other known limitations.

References

Molt is inspired by prior works such as

• deno-udd
• dmm
• updater

and of full respect to the authors.