Add fmt-project subcommand

CHANGELOG.md

@@ -6,6 +6,7 @@
 * Added the `gameId` and `placeId` optional properties to project files.
     * When connecting from the Rojo Roblox Studio plugin, Rojo will set the game and place ID of the current place to these values, if set.
     * This is equivalent to running `game:SetUniverseId(...)` and `game:SetPlaceId(...)` from the command bar in Studio. 
+* Added the `fmt-project` subcommand for formatting Rojo project files.
 * Added "EXPERIMENTAL!" label to two-way sync toggle in Rojo's Roblox Studio plugin.
 * Fixed `Name` and `Parent` properties being allowed in Rojo projects. ([#413][pr-413])
 * Fixed "Open Scripts Externally" feature crashing Studio. ([#369][issue-369])

src/bin.rs

@@ -11,6 +11,7 @@ fn run(global: GlobalOptions, subcommand: Subcommand) -> anyhow::Result<()> {
         Subcommand::Serve(serve_options) => cli::serve(global, serve_options)?,
         Subcommand::Build(build_options) => cli::build(build_options)?,
         Subcommand::Upload(upload_options) => cli::upload(upload_options)?,
+        Subcommand::FmtProject(fmt_options) => fmt_options.run()?,
         Subcommand::Doc => cli::doc()?,
         Subcommand::Plugin(plugin_options) => cli::plugin(plugin_options)?,
     }

src/cli/fmt_project.rs

@@ -0,0 +1,29 @@
+use std::path::PathBuf;
+
+use anyhow::Context;
+use structopt::StructOpt;
+
+use crate::project::Project;
+
+/// Reformat a Rojo project using the standard JSON formatting rules.
+#[derive(Debug, StructOpt)]
+pub struct FmtProjectCommand {
+    /// Path to the project to format. Defaults to the current directory.
+    #[structopt(default_value = "")]
+    pub project: PathBuf,
+}
+
+impl FmtProjectCommand {
+    pub fn run(self) -> anyhow::Result<()> {
+        let project = Project::load_fuzzy(&self.project)?
+            .context("A project file is required to run 'rojo fmt-project'")?;
+
+        let serialized = serde_json::to_string_pretty(&project)
+            .context("could not re-encode project file as JSON")?;
+
+        fs_err::write(&project.file_location, &serialized)
+            .context("could not write back to project file")?;
+
+        Ok(())
+    }
+}

src/cli/mod.rs

@@ -2,6 +2,7 @@
 
 mod build;
 mod doc;
+mod fmt_project;
 mod init;
 mod plugin;
 mod serve;
@@ -22,6 +23,7 @@ use thiserror::Error;
 
 pub use self::build::*;
 pub use self::doc::*;
+pub use self::fmt_project::FmtProjectCommand;
 pub use self::init::*;
 pub use self::plugin::*;
 pub use self::serve::*;
@@ -112,6 +114,8 @@ pub enum Subcommand {
     /// Generates a place or model file out of the project and uploads it to Roblox.
     Upload(UploadCommand),
 
+    FmtProject(FmtProjectCommand),
+
     /// Open Rojo's documentation in your browser.
     Doc,