base on A shell parser, formatter, and interpreter with bash support; includes shfmt # sh [](https://pkg.go.dev/mvdan.cc/sh/v3) A shell parser, formatter, and interpreter. Supports [POSIX Shell], [Bash], and [mksh]. Requires Go 1.23 or later. ### Quick start To parse shell scripts, inspect them, and print them out, see the [syntax package examples](https://pkg.go.dev/mvdan.cc/sh/v3/syntax#pkg-examples). For high-level operations like performing shell expansions on strings, see the [shell package examples](https://pkg.go.dev/mvdan.cc/sh/v3/shell#pkg-examples). ### shfmt go install mvdan.cc/sh/v3/cmd/shfmt@latest `shfmt` formats shell programs. See [canonical.sh](syntax/canonical.sh) for a quick look at its default style. For example: shfmt -l -w script.sh For more information, see [its manpage](cmd/shfmt/shfmt.1.scd), which can be viewed directly as Markdown or rendered with [scdoc]. Packages are available on [Alpine], [Arch], [Debian], [Docker], [Fedora], [FreeBSD], [Homebrew], [MacPorts], [NixOS], [OpenSUSE], [Scoop], [Snapcraft], [Void] and [webi]. ### gosh go install mvdan.cc/sh/v3/cmd/gosh@latest Proof of concept shell that uses `interp`. Note that it's not meant to replace a POSIX shell at the moment, and its options are intentionally minimalistic. ### Fuzzing We use Go's native fuzzing support. For instance: cd syntax go test -run=- -fuzz=ParsePrint ### Caveats * When indexing Bash associative arrays, always use quotes. The static parser will otherwise have to assume that the index is an arithmetic expression. ```sh $ echo '${array[spaced string]}' | shfmt 1:16: not a valid arithmetic operator: string $ echo '${array[dash-string]}' | shfmt ${array[dash - string]} ``` * `$((` and `((` ambiguity is not supported. Backtracking would complicate the parser and make streaming support via `io.Reader` impossible. The POSIX spec recommends to [space the operands][posix-ambiguity] if `$( (` is meant. ```sh $ echo '$((foo); (bar))' | shfmt 1:1: reached ) without matching $(( with )) ``` * `export`, `let`, and `declare` are parsed as keywords. This allows statically building their syntax tree, as opposed to keeping the arguments as a slice of words. It is also required to support `declare foo=(bar)`. Note that this means expansions like `declare {a,b}=c` are not supported. * The entire library is written in pure Go, which limits how closely the interpreter can follow POSIX Shell and Bash semantics. For example, Go does not support forking its own process, so subshells use a goroutine instead, meaning that real PIDs and file descriptors cannot be used directly. ### JavaScript The parser and formatter are available as a third party npm package called [sh-syntax], which bundles a version of this library compiled to WASM. Previously, we maintained an npm package called [mvdan-sh] which used GopherJS to bundle a JS version of this library. That npm package is now archived given its poor performance and GopherJS not being as actively developed. Any existing or new users should look at [sh-syntax] instead. ### Docker All release tags are published via [Docker], such as `v3.5.1`. The latest stable release is currently published as `v3`, and the latest development version as `latest`. The images only include `shfmt`; `-alpine` variants exist on Alpine Linux. To build a Docker image, run: docker build -t my:tag -f cmd/shfmt/Dockerfile . To use a Docker image, run: docker run --rm -u "$(id -u):$(id -g)" -v "$PWD:/mnt" -w /mnt my:tag <shfmt arguments> ### Related projects The following editor integrations wrap `shfmt`: - [BashSupport-Pro] - Bash plugin for JetBrains IDEs - [dockerfmt] - Dockerfile formatter using shfmt - [intellij-shellcript] - Intellij Jetbrains `shell script` plugin - [micro] - Editor with a built-in plugin - [neoformat] - (Neo)Vim plugin - [shell-format] - VS Code plugin - [vscode-shfmt] - VS Code plugin - [shfmt.el] - Emacs package - [Sublime-Pretty-Shell] - Sublime Text 3 plugin - [Trunk] - Universal linter, available as a CLI, VS Code plugin, and GitHub action - [vim-shfmt] - Vim plugin Other noteworthy integrations include: - [modd] - A developer tool that responds to filesystem changes - [prettier-plugin-sh] - [Prettier] plugin using [sh-syntax] - [sh-checker] - A GitHub Action that performs static analysis for shell scripts - [mdformat-shfmt] - [mdformat] plugin to format shell scripts embedded in Markdown with shfmt - [pre-commit-shfmt] - [pre-commit] shfmt hook [alpine]: https://pkgs.alpinelinux.org/packages?name=shfmt [arch]: https://archlinux.org/packages/extra/x86_64/shfmt/ [bash]: https://www.gnu.org/software/bash/ [BashSupport-Pro]: https://www.bashsupport.com/manual/editor/formatter/ [debian]: https://tracker.debian.org/pkg/golang-mvdan-sh [docker]: https://hub.docker.com/r/mvdan/shfmt/ [dockerfmt]: https://github.com/reteps/dockerfmt [editorconfig]: https://editorconfig.org/ [examples]: https://pkg.go.dev/mvdan.cc/sh/v3/syntax#pkg-examples [fedora]: https://packages.fedoraproject.org/pkgs/golang-mvdan-sh-3/shfmt/ [freebsd]: https://www.freshports.org/devel/shfmt [homebrew]: https://formulae.brew.sh/formula/shfmt [intellij-shellcript]: https://www.jetbrains.com/help/idea/shell-scripts.html [macports]: https://ports.macports.org/port/shfmt/details/ [mdformat-shfmt]: https://github.com/hukkin/mdformat-shfmt [mdformat]: https://github.com/executablebooks/mdformat [micro]: https://micro-editor.github.io/ [mksh]: http://www.mirbsd.org/mksh.htm [modd]: https://github.com/cortesi/modd [mvdan-sh]: https://www.npmjs.com/package/mvdan-sh [neoformat]: https://github.com/sbdchd/neoformat [nixos]: https://github.com/NixOS/nixpkgs/blob/HEAD/pkgs/tools/text/shfmt/default.nix [OpenSUSE]: https://build.opensuse.org/package/show/openSUSE:Factory/shfmt [posix shell]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html [posix-ambiguity]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_06_03 [pre-commit]: https://pre-commit.com [pre-commit-shfmt]: https://github.com/scop/pre-commit-shfmt [prettier-plugin-sh]: https://github.com/un-ts/prettier/tree/master/packages/sh [prettier]: https://prettier.io [scdoc]: https://sr.ht/~sircmpwn/scdoc/ [scoop]: https://github.com/ScoopInstaller/Main/blob/HEAD/bucket/shfmt.json [sh-checker]: https://github.com/luizm/action-sh-checker [sh-syntax]: https://github.com/un-ts/sh-syntax [shell-format]: https://marketplace.visualstudio.com/items?itemName=foxundermoon.shell-format [shfmt.el]: https://github.com/purcell/emacs-shfmt/ [snapcraft]: https://snapcraft.io/shfmt [sublime-pretty-shell]: https://github.com/aerobounce/Sublime-Pretty-Shell [trunk]: https://trunk.io/check [vim-shfmt]: https://github.com/z0mbix/vim-shfmt [void]: https://github.com/void-linux/void-packages/blob/HEAD/srcpkgs/shfmt/template [vscode-shfmt]: https://marketplace.visualstudio.com/items?itemName=mkhl.shfmt [webi]: https://webinstall.dev/shfmt/ ", Assign "at most 3 tags" to the expected json: {"id":"7840","tags":[]} "only from the tags list I provide: [{"id":77,"name":"3d"},{"id":89,"name":"agent"},{"id":17,"name":"ai"},{"id":54,"name":"algorithm"},{"id":24,"name":"api"},{"id":44,"name":"authentication"},{"id":3,"name":"aws"},{"id":27,"name":"backend"},{"id":60,"name":"benchmark"},{"id":72,"name":"best-practices"},{"id":39,"name":"bitcoin"},{"id":37,"name":"blockchain"},{"id":1,"name":"blog"},{"id":45,"name":"bundler"},{"id":58,"name":"cache"},{"id":21,"name":"chat"},{"id":49,"name":"cicd"},{"id":4,"name":"cli"},{"id":64,"name":"cloud-native"},{"id":48,"name":"cms"},{"id":61,"name":"compiler"},{"id":68,"name":"containerization"},{"id":92,"name":"crm"},{"id":34,"name":"data"},{"id":47,"name":"database"},{"id":8,"name":"declarative-gui "},{"id":9,"name":"deploy-tool"},{"id":53,"name":"desktop-app"},{"id":6,"name":"dev-exp-lib"},{"id":59,"name":"dev-tool"},{"id":13,"name":"ecommerce"},{"id":26,"name":"editor"},{"id":66,"name":"emulator"},{"id":62,"name":"filesystem"},{"id":80,"name":"finance"},{"id":15,"name":"firmware"},{"id":73,"name":"for-fun"},{"id":2,"name":"framework"},{"id":11,"name":"frontend"},{"id":22,"name":"game"},{"id":81,"name":"game-engine "},{"id":23,"name":"graphql"},{"id":84,"name":"gui"},{"id":91,"name":"http"},{"id":5,"name":"http-client"},{"id":51,"name":"iac"},{"id":30,"name":"ide"},{"id":78,"name":"iot"},{"id":40,"name":"json"},{"id":83,"name":"julian"},{"id":38,"name":"k8s"},{"id":31,"name":"language"},{"id":10,"name":"learning-resource"},{"id":33,"name":"lib"},{"id":41,"name":"linter"},{"id":28,"name":"lms"},{"id":16,"name":"logging"},{"id":76,"name":"low-code"},{"id":90,"name":"message-queue"},{"id":42,"name":"mobile-app"},{"id":18,"name":"monitoring"},{"id":36,"name":"networking"},{"id":7,"name":"node-version"},{"id":55,"name":"nosql"},{"id":57,"name":"observability"},{"id":46,"name":"orm"},{"id":52,"name":"os"},{"id":14,"name":"parser"},{"id":74,"name":"react"},{"id":82,"name":"real-time"},{"id":56,"name":"robot"},{"id":65,"name":"runtime"},{"id":32,"name":"sdk"},{"id":71,"name":"search"},{"id":63,"name":"secrets"},{"id":25,"name":"security"},{"id":85,"name":"server"},{"id":86,"name":"serverless"},{"id":70,"name":"storage"},{"id":75,"name":"system-design"},{"id":79,"name":"terminal"},{"id":29,"name":"testing"},{"id":12,"name":"ui"},{"id":50,"name":"ux"},{"id":88,"name":"video"},{"id":20,"name":"web-app"},{"id":35,"name":"web-server"},{"id":43,"name":"webassembly"},{"id":69,"name":"workflow"},{"id":87,"name":"yaml"}]" returns me the "expected json"