Add support for JSON input

Summary:
Add support for JSON input in mini-elp, for commands `eqwalize` and `eqwalize-all`.

## Usage

`elp eqwalize-all --project path/to/build_info.json`

## JSON file structure

The `build_info.json` file is structured this way:
```
{
  "apps": [app list],
  "deps": [app list], // Defaults to []
  "root": "path/to/root" // Defaults to ""
}
```

Where an `app` is a map structured as follows:
```
// app
{
  "name": "app_name",
  "dir": "path/to/app", // Relative to project root
  "src_dirs": ["path/to/src", ...], // Relative to app dir, defaults to ["src"]
  "extra_src_dirs": ["path/to/extra_src", ...], // Relative to app dir, defaults to []
  "ebin": "path/to/ebin", // Relative to app dir, defaults to "ebin"
  "include_dirs": ["include", ...], // Relative to app dir, defaults to []
  "macros": ["MACRO", ...], // Defaults to []
}
```

Reviewed By: ilya-klyuchnikov, michalmuskala

Differential Revision: D40834799

fbshipit-source-id: 159a4c61d450fa5232eb356e2113a8709911b809

Author: VLanvin

mini-elp/Cargo.lock

@@ -83,11 +83,11 @@ COMMANDS:
         --offset-positions     Emit positions as {StartByte, EndByte} rather than {Line, Col}
         --module               Only process indicated module(s) (can be repeated)
     eqwalize <module>          Eqwalize specified module
-        --project              Path to directory with rebar project (defaults to `.`)
+        --project              Path to directory with rebar project, or to a JSON file (defaults to `.`)
         --fast                 Refresh AST information for only the specified module
         --format FORMAT        Specify format for the diagnostics. FORMAT can be `pretty` (default), `json` or `json-lsp`
     eqwalize-all               Eqwalize all opted-in modules in a project (modules with `-typing([eqwalizer])`)
-        --project              Path to directory with rebar project (defaults to `.`)
+        --project              Path to directory with rebar project, or to a JSON file (defaults to `.`)
         --format FORMAT        Specify format for the diagnostics. FORMAT can be `pretty` (default), `json` or `json-lsp`
 
 ENV VARS:

mini-elp/crates/elp/src/bin/args.rs

@@ -35,8 +35,16 @@ struct EqwalizerInternalArgs<'a> {
 }
 
 pub fn eqwalize_module(args: &Eqwalize, mut out: impl WriteColor) -> Result<()> {
-    let profile = args.profile.clone().map(Profile).unwrap_or_default();
-    let loaded = &load_rebar::load_project_with_caching_at(&args.project, &profile, args.fast)?;
+    let loaded = &match args.project.extension() {
+        None => {
+            let profile = args.profile.clone().map(Profile).unwrap_or_default();
+            load_rebar::load_project_with_caching_at(&args.project, &profile, args.fast)
+        }
+        Some(ext) => match ext.to_str() {
+            Some("json") => load_rebar::load_json_project_at(&args.project),
+            _ => panic!("Unknown file type for option --project"),
+        },
+    }?;
     let analysis = &loaded.analysis();
     let file_id = analysis
         .module_file_id(loaded.project_id, &args.module)?
@@ -57,8 +65,16 @@ pub fn eqwalize_module(args: &Eqwalize, mut out: impl WriteColor) -> Result<()>
 }
 
 pub fn eqwalize_all(args: &EqwalizeAll, mut out: impl WriteColor) -> Result<()> {
-    let profile = args.profile.clone().map(Profile).unwrap_or_default();
-    let loaded = &load_rebar::load_project_at(&args.project, &profile)?;
+    let loaded = &match args.project.extension() {
+        None => {
+            let profile = args.profile.clone().map(Profile).unwrap_or_default();
+            load_rebar::load_project_at(&args.project, &profile)
+        }
+        Some(ext) => match ext.to_str() {
+            Some("json") => load_rebar::load_json_project_at(&args.project),
+            _ => panic!("Unknown file type for option --project"),
+        },
+    }?;
     let analysis = &loaded.analysis();
 
     let mut reporter: Box<dyn reporting::Reporter> = match args.format {

mini-elp/crates/elp/src/bin/eqwalizer_cli.rs

@@ -83,6 +83,17 @@ impl LoadResult {
     }
 }
 
+pub fn load_json_project_at(json: &Path) -> Result<LoadResult> {
+    let json_file = AbsPathBuf::assert(std::env::current_dir()?.join(json)).normalize();
+    let manifest = ProjectManifest::from_json_file(json_file);
+
+    let pb = util::spinner("Loading JSON manifest", "Loaded JSON manifest");
+    let project = Project::load(manifest)?;
+    pb.finish();
+
+    load_project(project)
+}
+
 pub fn load_project_at(root: &Path, project_profile: &Profile) -> Result<LoadResult> {
     let root = AbsPathBuf::assert(std::env::current_dir()?.join(root));
     let root = ProjectManifest::discover_single(&root, project_profile)?;

mini-elp/crates/elp/src/bin/load_rebar.rs

@@ -16,11 +16,11 @@ COMMANDS:
         --offset-positions     Emit positions as {StartByte, EndByte} rather than {Line, Col}
         --module               Only process indicated module(s) (can be repeated)
     eqwalize <module>          Eqwalize specified module
-        --project              Path to directory with rebar project (defaults to `.`)
+        --project              Path to directory with rebar project, or to a JSON file (defaults to `.`)
         --fast                 Refresh AST information for only the specified module
         --format FORMAT        Specify format for the diagnostics. FORMAT can be `pretty` (default), `json` or `json-lsp`
     eqwalize-all               Eqwalize all opted-in modules in a project (modules with `-typing([eqwalizer])`)
-        --project              Path to directory with rebar project (defaults to `.`)
+        --project              Path to directory with rebar project, or to a JSON file (defaults to `.`)
         --format FORMAT        Specify format for the diagnostics. FORMAT can be `pretty` (default), `json` or `json-lsp`
 
 ENV VARS:

mini-elp/crates/elp/src/resources/test/help.stderr

@@ -12,5 +12,7 @@ fxhash.workspace = true
 lazy_static.workspace = true
 log.workspace = true
 paths.workspace = true
+serde.workspace = true
+serde_json.workspace = true
 tempfile.workspace = true
 walkdir.workspace = true