elm-review from Node.js.
# Save it to your package.json, if you use npm in your project.# This is the recommended way.npm install elm-review --save-dev# Install globally. This is not recommended.npm install -g elm-review
See below if you want to try it out without installing it.
# Print the helpelm-review --help# Review your projectelm-review# Create an empty review configurationelm-review init# Create a new project containing elm-review rules# aimed at being published on the Elm package registryelm-review new-package# Create an empty new rule to get started.# Very helpful for projects created with new-packageelm-review new-rule
Try it out
You can try
elm-review out without setting up anything!
First of all, if you have
node installed, it comes with
npx, which lets you run
elm-review without installing it by prepending the command by
npx elm-review. It is a bit slower and requires Internet access, but it's useful to try it out.
You can also run a configuration you found on GitHub, using the
--template flag. Even if you already have a configuration, you can use this to try out the rules from a new package before adding them to your configuration.
For instance, if you want to find and remove the dead code in your project, you can use the example configuration from the
npx elm-review --template jfmengels/elm-review-unused/example# You can even use the configuration to fix all the errors that can be auto-fixed.npx elm-review --template jfmengels/elm-review-unused/example --fix-all
If you are happy with the configuration, you can base your own configuration off of it, and then edit it:
npx elm-review init --template jfmengels/elm-review-unused/example
I highly recommend reading this section on when to enable rules in your configuration though.
You can use the same mechanic to try out a single rule before adding the dependency to your existing configuration and adding it to your configuration.
npx elm-review --template jfmengels/elm-review-unused/example --rules NoUnused.Variables
elm-review for the first time, you need to run
elm-review initelm-review init --help # for more information and the available flags
This will create a
review/ directory containing an
elm.json and a
ReviewConfig.elm file, which you should commit into your project. Here is what it may look like:
module ReviewConfig exposing (config)import Review.Rule exposing Ruleimport NoDebugimport NoUnused.Variablesconfig : List Ruleconfig =[ NoDebug.rule, NoUnused.Variables.rule]
elm-review does not come with any built-in rules. You can read why here. You can find rules in the Elm package registry by using
elm-search and searching for
Review.Rule.Rule, and use them by going to your
review/ directory and running
elm install in your terminal.
cd review/ # Go inside your review configuration directoryelm install authorName/packageName
Run a review
Once you're done configuring, run
elm-review to analyze your project.
You can also run
elm-review --fix. The CLI will present you fixes for the errors that offer an automatic fix, which you can then accept or not. When there are no more fixable errors left,
elm-review will report the remaining errors as if it was called without
--fix. Fixed errors will be reformatted using
elm-review --help for more information on the available flags.
elm-review # Analyze your projectelm-review --fix # Analyze your project and potentially proposes automatic fixeselm-review --help # for more information and the available flags
Which parts of the project will be analyzed?
elm-review targets a project, and therefore requires an
elm.json. By default, it will review all the Elm files of the project and of the tests.
- For packages: all the Elm files in
- For applications: all the Elm files in
tests/and in the project's
If you wish to, you can list the directories you wish to have reviewed, so as to review additional directories or to remove ignore some of directories, by adding them as arguments to the command line.
# Review `src/` if project is a package, or the "source-directories" otherwise, along with `tests/`elm-review# Review only the Elm files in the `src/Dashboard/`elm-review src/Dashboard/# Review all the Elm files in the src/, tests/ and review/ directorieselm-review src/ tests/ review/# Review a specific fileelm-review src/Dashboard.elm
The recommended way to use
elm-review is without arguments. It is best not to "remove" directories from the project, because some rules expect to have access to all the files in order to make the best analysis. If some data is missing, they may make incorrect reports. If you wish to ignore some files, it is best to handle that in the implementation and/or configuration of your rules.
If you add files that are not part of the project, you may run into different problems, such as conflicting module names (two
Main.elm files), relying on different dependencies, etc. It is best to run
elm-review once for each project, and depending on your needs, with different configurations (using the
If any rule from your configuration reports an error in one of the analyzed files, the process will exit with status 1. Otherwise, it will exit with status 0.
If the process fails for any other reason (crash, misconfiguration, ...), it will exit with status 1.
Why is there a need for a review/ directory?
When the CLI looks at your configuration, it is in practice compiling an application using the configuration in your project, then running that application to analyze your project.
The CLI need at least two pieces of information from your configuration:
elm.jsonfile to know the external packages your configuration depends upon (like the ones that contain the rules you enabled), and the Elm version of your project
ReviewConfig.elmfile that sets the rules to enforce for your project
Your custom rules, unless you want to share them in the Elm package registry, should be in the
review/ directory too, so as not to pollute your project's dependencies. If they are in here, we need to include these custom rules and their dependencies in the application files.
If you are interested in using
elm-review inside a different environment than a terminal (like editors, CI, other Elm tools, ...), check out the documentation for tooling integration.
Thanks to @MartinSStewart for working on reducing the file cache size (and therefore speeding up the whole execution).