From a72ebbeafcfc0364407dc5a94151ebf10152408b Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Thu, 26 Sep 2024 10:24:37 +0200
Subject: [PATCH] Add a `cargo machete` CI step (#5171)

`cargo machete` looks for unused dependencies
---
 .github/workflows/cargo_machete.yml           | 12 ++++++++++++
 Cargo.lock                                    |  2 --
 RELEASES.md                                   |  1 -
 crates/egui-winit/Cargo.toml                  |  1 -
 crates/egui_demo_lib/Cargo.toml               |  1 -
 examples/custom_style/Cargo.toml              |  5 +++++
 examples/hello_world_par/Cargo.toml           |  4 ++++
 examples/images/Cargo.toml                    |  4 ++++
 tests/test_egui_extras_compilation/Cargo.toml |  2 ++
 9 files changed, 27 insertions(+), 5 deletions(-)
 create mode 100644 .github/workflows/cargo_machete.yml

diff --git a/.github/workflows/cargo_machete.yml b/.github/workflows/cargo_machete.yml
new file mode 100644
index 00000000000..dab6725553c
--- /dev/null
+++ b/.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
diff --git a/Cargo.lock b/Cargo.lock
index 1a2423eaa8a..2c509d7462b 100644
--- a/Cargo.lock
+++ b/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",
 ]
diff --git a/RELEASES.md b/RELEASES.md
index b825eef8df5..99aec8ef382 100644
--- a/RELEASES.md
+++ b/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 * [ ] `cargo outdated` (or manually look for outdated crates in each `Cargo.toml`)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
diff --git a/crates/egui-winit/Cargo.toml b/crates/egui-winit/Cargo.toml
index 4472c70f552..f8a11ec7a36 100644
--- a/crates/egui-winit/Cargo.toml
+++ b/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 }
diff --git a/crates/egui_demo_lib/Cargo.toml b/crates/egui_demo_lib/Cargo.toml
index cc41e923abe..28b0592c228 100644
--- a/crates/egui_demo_lib/Cargo.toml
+++ b/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
diff --git a/examples/custom_style/Cargo.toml b/examples/custom_style/Cargo.toml
index 23f8a4e93c8..c7ae125493a 100644
--- a/examples/custom_style/Cargo.toml
+++ b/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",
diff --git a/examples/hello_world_par/Cargo.toml b/examples/hello_world_par/Cargo.toml
index a64e7c0e9b0..458847eba4f 100644
--- a/examples/hello_world_par/Cargo.toml
+++ b/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
diff --git a/examples/images/Cargo.toml b/examples/images/Cargo.toml
index 57d552e3be4..fd6ed440b39 100644
--- a/examples/images/Cargo.toml
+++ b/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",
diff --git a/tests/test_egui_extras_compilation/Cargo.toml b/tests/test_egui_extras_compilation/Cargo.toml
index 167a8fa288c..aa1ea2c7ec9 100644
--- a/tests/test_egui_extras_compilation/Cargo.toml
+++ b/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"] }