test(shell-env): cover noisy JSON and exit status

crates/moon-util/src/shell_env.rs

@@ -349,3 +349,6 @@ mod tests {
         );
     }
 }
+
+#[cfg(test)]
+mod shell_env_tests;

crates/moon-util/src/shell_env/shell_env_tests.rs

@@ -0,0 +1,113 @@
+use std::process::ExitStatus;
+
+use super::{parse_env_map_from_noisy_output, parse_env_output};
+
+/// Builds an `ExitStatus` whose code is `code` on the host platform.
+#[cfg(unix)]
+fn exit_status(code: i32) -> ExitStatus {
+    use std::os::unix::process::ExitStatusExt;
+
+    ExitStatus::from_raw(code << 8)
+}
+
+/// Builds an `ExitStatus` whose code is `code` on the host platform.
+#[cfg(windows)]
+fn exit_status(code: u32) -> ExitStatus {
+    use std::os::windows::process::ExitStatusExt;
+
+    ExitStatus::from_raw(code)
+}
+
+/// Catches `parse_env_map_from_noisy_output` stopping at the first `{`, so a
+/// shell banner that contains a brace hides the environment JSON after it.
+#[test]
+fn later_json_object_is_used_when_an_earlier_brace_is_not_a_map() {
+    let output = "banner {not-json} tail {\"PATH\":\"/usr/bin\",\"HOME\":\"/home/dev\"} done";
+
+    let env_map = parse_env_map_from_noisy_output(output)
+        .expect("the object after the banner brace should parse");
+
+    assert_eq!(env_map.get("PATH").map(String::as_str), Some("/usr/bin"));
+    assert_eq!(env_map.get("HOME").map(String::as_str), Some("/home/dev"));
+    assert_eq!(env_map.len(), 2);
+}
+
+/// Catches `parse_env_map_from_noisy_output` reporting success when the shell
+/// printed no JSON, so a failed capture looks like an empty environment.
+#[test]
+fn missing_json_is_an_error() {
+    let output = "shell ready, no environment";
+
+    let error = parse_env_map_from_noisy_output(output)
+        .expect_err("output with no JSON object should be an error");
+
+    let message = error.to_string();
+    assert!(
+        message.contains("Failed to find JSON in shell output"),
+        "{message}"
+    );
+    assert!(message.contains(output), "{message}");
+}
+
+/// Catches `parse_env_output` treating a zero exit as a failure after the
+/// environment JSON parsed, so a healthy login shell is discarded.
+#[test]
+fn successful_exit_returns_parsed_env_without_either_callback() {
+    let env_map = parse_env_output(
+        "noise\n{\"PATH\":\"/usr/bin\"}\n",
+        &exit_status(0),
+        || panic!("warning should not run when the shell exited 0"),
+        || panic!("failure message should not run when the JSON parsed"),
+    )
+    .expect("parsed environment JSON should be returned on a zero exit");
+
+    assert_eq!(env_map.get("PATH").map(String::as_str), Some("/usr/bin"));
+    assert_eq!(env_map.len(), 1);
+}
+
+/// Catches `parse_env_output` dropping the shell's own error when the output
+/// is not JSON and the process exited non-zero, so the caller only sees a
+/// parse failure.
+#[test]
+fn failed_exit_with_unparseable_output_includes_the_shell_error() {
+    let error = parse_env_output(
+        "not json",
+        &exit_status(1),
+        || panic!("warning is only for a parsed environment"),
+        || "shell died".to_string(),
+    )
+    .expect_err("unparseable output should be an error");
+
+    let message = error.to_string();
+    assert!(message.contains("shell died"), "{message}");
+    assert!(
+        message.contains("Failed to deserialize environment variables from json"),
+        "{message}"
+    );
+    assert!(message.contains("not json"), "{message}");
+}
+
+/// Catches `parse_env_output` blaming a shell crash when the process exited
+/// zero and the output was not JSON, so a successful command is reported as
+/// a failure of the shell itself.
+#[test]
+fn successful_exit_with_unparseable_output_omits_the_shell_error() {
+    let error = parse_env_output(
+        "not json",
+        &exit_status(0),
+        || panic!("warning is only for a parsed environment"),
+        || "shell died".to_string(),
+    )
+    .expect_err("unparseable output should be an error");
+
+    let message = error.to_string();
+    assert!(
+        !message.contains("shell died"),
+        "zero exit should not include the shell-failure text: {message}"
+    );
+    assert!(
+        message.contains("Failed to deserialize environment variables from json"),
+        "{message}"
+    );
+    assert!(message.contains("not json"), "{message}");
+}