add fmt and clippy tests as part of the test process

So we don't have to have a separate CI target.
This is easier to reason, and it's a single test

.github/workflows/ci.yml

@@ -10,26 +10,6 @@ on:
     branches: [ master ]
 
 jobs:
-  fmt:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-
-      - name: Cache setup
-        uses: ./.github/actions/cache-setup
-
-      - name: Install nightly for rustfmt features
-        run: |
-          FMT_NIGHTLY=nightly-$(curl -s https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu/rustfmt)
-          rustup install nightly
-          rustup default "$FMT_NIGHTLY"
-          rustup component add rustfmt
-
-      - name: Check formatting
-        run: cargo fmt --all -- --check
-
   doc:
     runs-on: ubuntu-latest
 
@@ -50,35 +30,6 @@ jobs:
     # - name: Validate links
     #   run: cargo deadlinks --dir target/doc/glommio
 
-  toml:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-
-      - name: Cache setup
-        uses: ./.github/actions/cache-setup
-
-      - name: Install cargo-sort
-        run: cargo install cargo-sort
-
-      - name: Sort Cargo.toml
-        run: cargo sort -w --check
-
-  clippy:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-
-      - name: Cache setup
-        uses: ./.github/actions/cache-setup
-
-      - name: Run linters
-        run: cargo clippy --all-targets --all-features -- -D warnings
-
   build:
     runs-on: ubuntu-latest
 
@@ -102,5 +53,15 @@ jobs:
       - name: Cache setup
         uses: ./.github/actions/cache-setup
 
-      - name: Test all targets
-        run: sudo bash -c "ulimit -Sl 512 && ulimit -Hl 512 && PATH=$PATH:/usr/share/rust/.cargo/bin && RUSTUP_TOOLCHAIN=stable cargo test --all-features"
+      - name: Install cargo helpers and test all targets 
+        run: |
+          cat << EOF > "run-gha-workflow.sh"
+          PATH=$PATH:/usr/share/rust/.cargo/bin
+          rustup install nightly
+          rustup component add rustfmt --toolchain nightly-x86_64-unknown-linux-gnu
+          rustup show
+          rustup default stable
+          cargo install cargo-sort
+          cargo test --all-features
+          EOF
+          sudo -E bash -c "ulimit -Sl 512 && ulimit -Hl 512 && bash run-gha-workflow.sh"

glommio/tests/linters.rs

@@ -0,0 +1,49 @@
+// Unless explicitly stated otherwise all files in this repository are licensed
+// under the MIT/Apache-2.0 License, at your convenience
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2020
+// Datadog, Inc.
+#[cfg(test)]
+mod tests {
+    use std::process::Command;
+    #[test]
+    fn check_formating() {
+        let status = Command::new("cargo")
+            .args(["+nightly", "fmt", "--all", "--", "--check"])
+            .status()
+            .unwrap();
+        assert!(
+            status.success(),
+            "cargo fmt failed. Note that glommio uses nightly for formatting, so please invoke \
+             cargo with +nightly"
+        );
+    }
+
+    #[test]
+    fn check_clippy() {
+        let status = Command::new("cargo")
+            .args([
+                "clippy",
+                "--all-targets",
+                "--all-features",
+                "--",
+                "-D",
+                "warnings",
+            ])
+            .status()
+            .unwrap();
+        assert!(status.success());
+    }
+
+    #[test]
+    fn check_dependencies_sorted() {
+        let status = Command::new("cargo")
+            .args(["sort", "-w", "-c"])
+            .status()
+            .unwrap();
+        assert!(
+            status.success(),
+            "cargo-sort not installed or cargo.toml dependencies not sorted"
+        );
+    }
+}