nautilus_core/
env.rs

1// -------------------------------------------------------------------------------------------------
2//  Copyright (C) 2015-2025 Nautech Systems Pty Ltd. All rights reserved.
3//  https://nautechsystems.io
4//
5//  Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
6//  You may not use this file except in compliance with the License.
7//  You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
8//
9//  Unless required by applicable law or agreed to in writing, software
10//  distributed under the License is distributed on an "AS IS" BASIS,
11//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12//  See the License for the specific language governing permissions and
13//  limitations under the License.
14// -------------------------------------------------------------------------------------------------
15
16//! Cross-platform environment variable utilities.
17//!
18//! This module provides functions for safely accessing environment variables
19//! with proper error handling.
20
21/// Returns the value of the environment variable for the given `key`.
22///
23/// # Errors
24///
25/// Returns an error if the environment variable is not set.
26pub fn get_env_var(key: &str) -> anyhow::Result<String> {
27    match std::env::var(key) {
28        Ok(var) => Ok(var),
29        Err(_) => anyhow::bail!("environment variable '{key}' must be set"),
30    }
31}
32
33////////////////////////////////////////////////////////////////////////////////
34// Tests
35////////////////////////////////////////////////////////////////////////////////
36#[cfg(test)]
37mod tests {
38    use rstest::*;
39
40    use super::*;
41
42    #[rstest]
43    fn test_get_env_var_success() {
44        // Test with a commonly available environment variable
45        if let Ok(path) = std::env::var("PATH") {
46            let result = get_env_var("PATH");
47            assert!(result.is_ok());
48            assert_eq!(result.unwrap(), path);
49        }
50    }
51
52    #[rstest]
53    fn test_get_env_var_not_set() {
54        // Use a highly unlikely environment variable name
55        let result = get_env_var("NONEXISTENT_ENV_VAR_THAT_SHOULD_NOT_EXIST_12345");
56        assert!(result.is_err());
57        assert!(result.unwrap_err().to_string().contains(
58            "environment variable 'NONEXISTENT_ENV_VAR_THAT_SHOULD_NOT_EXIST_12345' must be set"
59        ));
60    }
61
62    #[rstest]
63    fn test_get_env_var_error_message_format() {
64        let var_name = "DEFINITELY_NONEXISTENT_VAR_123456789";
65        let result = get_env_var(var_name);
66        assert!(result.is_err());
67        let error_msg = result.unwrap_err().to_string();
68        assert!(error_msg.contains(var_name));
69        assert!(error_msg.contains("must be set"));
70    }
71}
nautilus_core/env.rs

nautilus_core/
env.rs
