Add a cargo machete CI step (emilk#5171)

`cargo machete` looks for unused dependencies

.github/workflows/cargo_machete.yml

@@ -0,0 +1,12 @@
+name: Cargo Machete
+
+on: [push, pull_request]
+
+jobs:
+  cargo-machete:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Machete
+        uses: bnjbvr/cargo-machete@main

Cargo.lock

@@ -1261,7 +1261,6 @@ dependencies = [
  "document-features",
  "egui",
  "log",
- "nix",
  "puffin",
  "raw-window-handle 0.6.2",
  "serde",
@@ -1306,7 +1305,6 @@ dependencies = [
  "document-features",
  "egui",
  "egui_extras",
- "log",
  "serde",
  "unicode_names2",
 ]

RELEASES.md

@@ -33,7 +33,6 @@ We don't update the MSRV in a patch release, unless we really, really need to.
 * [ ] `./scripts/docs.sh`: read and improve documentation of new stuff
 * [ ] `cargo update`
 * [ ] `cargo outdated` (or manually look for outdated crates in each `Cargo.toml`)
-* [ ] `cargo machete`
 
 ## Release testing
 * [ ] `cargo r -p egui_demo_app` and click around for while

crates/egui-winit/Cargo.toml

@@ -62,7 +62,6 @@ egui = { workspace = true, default-features = false, features = ["log"] }
 
 ahash.workspace = true
 log.workspace = true
-nix = { version = "0.26.4", default-features = false, optional = true }
 raw-window-handle.workspace = true
 web-time.workspace = true
 winit = { workspace = true, default-features = false }

crates/egui_demo_lib/Cargo.toml

@@ -45,7 +45,6 @@ syntect = ["egui_extras/syntect"]
 egui = { workspace = true, default-features = false, features = ["color-hex"] }
 egui_extras = { workspace = true, features = ["default"] }
 
-log.workspace = true
 unicode_names2 = { version = "0.6.0", default-features = false } # this old version has fewer dependencies
 
 #! ### Optional dependencies

examples/custom_style/Cargo.toml

@@ -9,6 +9,11 @@ publish = false
 [lints]
 workspace = true
 
+
+[package.metadata.cargo-machete]
+ignored = ["image"] # We need the .png feature
+
+
 [dependencies]
 eframe = { workspace = true, features = [
     "default",

examples/hello_world_par/Cargo.toml

@@ -11,6 +11,10 @@ publish = false
 workspace = true
 
 
+[package.metadata.cargo-machete]
+ignored = ["winit"] # Just enable some features of it; see below
+
+
 [dependencies]
 eframe = { workspace = true, default-features = false, features = [
     # accesskit struggles with threading

examples/images/Cargo.toml

@@ -11,6 +11,10 @@ publish = false
 workspace = true
 
 
+[package.metadata.cargo-machete]
+ignored = ["image"] # We only use the dependency to add more features to it
+
+
 [dependencies]
 eframe = { workspace = true, features = [
   "default",

tests/test_egui_extras_compilation/Cargo.toml

@@ -9,6 +9,8 @@ publish = false
 [lints]
 workspace = true
 
+[package.metadata.cargo-machete]
+ignored = ["eframe", "egui_extras"] # We don't use them, just check that things compile
 
 [dependencies]
 eframe = { workspace = true, features = ["default", "persistence"] }