Add tests and enable GitHub Actions to run the tests on every push

.github/workflows/ci.yml

@@ -0,0 +1,20 @@
+name: CI
+
+on:
+    push:
+    pull_request:
+    workflow_dispatch:
+
+jobs:
+  generate:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Run tests
+        run: |
+            cargo test
+
+      #- name: Run cargo fmt --check
+      #  run: cargo fmt --check
+

tests/a.txt

@@ -0,0 +1,2 @@
+First example
+Second row

tests/wc.rs

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+use std::process::Command;
+
+#[test]
+fn simple_wc() {
+    let result = Command::new("cargo")
+    .arg("build")
+    .arg("--release")
+    .output()
+    .expect("Could not run");
+    assert_eq!(result.status.code(), Some(0));
+
+
+    let result = Command::new("target/release/wc-rs")
+    .arg("tests/a.txt")
+    .output()
+    .expect("Could not run");
+    assert_eq!(result.status.code(), Some(0));
+    assert_eq!(std::str::from_utf8(&result.stdout).unwrap(), "2\t4\t25\t\u{1b}[2;32mtests/a.txt\u{1b}[0m\n");
+    assert_eq!(std::str::from_utf8(&result.stderr).unwrap(), "");
+
+
+    let result = Command::new("target/release/wc-rs")
+    .arg("tests/empty.txt")
+    .output()
+    .expect("Could not run");
+    assert_eq!(result.status.code(), Some(0));
+    assert_eq!(std::str::from_utf8(&result.stdout).unwrap(), "0\t0\t0\t\u{1b}[2;32mtests/empty.txt\u{1b}[0m\n");
+    assert_eq!(std::str::from_utf8(&result.stderr).unwrap(), "");
+
+}
+