tests: add tests for download --install-file

tests/assertions/mod.rs

@@ -2,6 +2,7 @@
 #![allow(clippy::uninlined_format_args)]
 
 use crate::docker::ExecResult;
+use std::path::Path;
 
 pub fn assert_success(result: ExecResult) -> String {
     match result {
@@ -29,3 +30,9 @@ pub fn assert_contains(expected: &str, actual: &str) {
         expected
     )
 }
+
+pub fn assert_file_exists(path: &Path) {
+    if !path.exists() {
+        panic!("File does not exist: {:?}", path)
+    }
+}

tests/integration_tests.rs

@@ -1,3 +1,5 @@
+mod assertions;
+mod docker;
 mod fs;
 
 mod archives {
@@ -8,6 +10,8 @@ mod archives {
     use assert_cmd::assert::OutputAssertExt;
     use assert_cmd::prelude::CommandCargoExt;
 
+    use crate::assertions::assert_file_exists;
+
     #[cfg(target_family = "unix")]
     #[test_case("helloworld.tar.gz"; "tar gzip")]
     #[test_case("helloworld.tgz"; "tar tgz")]
@@ -77,6 +81,52 @@ mod archives {
             .failure()
             .stderr(predicates::str::contains("No executable found"));
     }
+
+    #[cfg(target_family = "unix")]
+    #[test_case("helloworld-many-executables-unix.tar.gz", "helloworld-v2"; "install helloworld-v2")]
+    fn install_file_successfully(asset: &str, file: &str) {
+        let temp_dir = any_temp_dir();
+        let expected_installed_file = temp_dir.join(file);
+        let output_dir = path_to_string(temp_dir);
+
+        let mut cmd = Command::cargo_bin("dra").unwrap();
+
+        let result = cmd
+            .arg("download")
+            .args(["-I", file])
+            .args(["-s", asset])
+            .args(["-o", &output_dir])
+            .arg("devmatteini/dra-tests")
+            .assert();
+
+        result
+            .success()
+            .stdout(predicates::str::contains("Installation completed"));
+        assert_file_exists(&expected_installed_file);
+    }
+
+    #[cfg(target_os = "windows")]
+    #[test_case("helloworld-many-executables-windows.zip", "helloworld-v2.exe"; "install helloworld-v2.exe")]
+    fn install_file_successfully(asset: &str, file: &str) {
+        let temp_dir = any_temp_dir();
+        let expected_installed_file = temp_dir.join(file);
+        let output_dir = path_to_string(temp_dir);
+
+        let mut cmd = Command::cargo_bin("dra").unwrap();
+
+        let result = cmd
+            .arg("download")
+            .args(["-I", file])
+            .args(["-s", asset])
+            .args(["-o", &output_dir])
+            .arg("devmatteini/dra-tests")
+            .assert();
+
+        result
+            .success()
+            .stdout(predicates::str::contains("Installation completed"));
+        assert_file_exists(&expected_installed_file);
+    }
 }
 
 mod download {