Use unit tests to keep private things private

ui_test/src/comments.rs

@@ -2,6 +2,9 @@ use std::path::Path;
 
 use regex::Regex;
 
+#[cfg(test)]
+mod tests;
+
 /// This crate supports various magic comments that get parsed as file-specific
 /// configuration values. This struct parses them all in one go and then they
 /// get processed by their respective use sites.

ui_test/src/comments/tests.rs

@@ -1,6 +1,6 @@
 use std::path::Path;
 
-use ui_test::Comments;
+use super::Comments;
 
 #[test]
 fn parse_simple_comment() {

ui_test/src/lib.rs

@@ -12,6 +12,8 @@ use regex::Regex;
 pub use crate::comments::Comments;
 
 mod comments;
+#[cfg(test)]
+mod tests;
 
 #[derive(Debug)]
 pub struct Config {
@@ -171,7 +173,7 @@ pub fn run_tests(config: Config) {
 }
 
 #[derive(Debug)]
-pub enum Error {
+enum Error {
     /// Got an invalid exit status for the given mode.
     ExitStatus(Mode, ExitStatus),
     PatternNotFound {
@@ -191,7 +193,7 @@ pub enum Error {
     },
 }
 
-pub type Errors = Vec<Error>;
+type Errors = Vec<Error>;
 
 fn run_test(
     path: &Path,
@@ -249,7 +251,7 @@ fn run_test(
     (miri, errors)
 }
 
-pub fn check_annotations(
+fn check_annotations(
     unnormalized_stderr: &[u8],
     errors: &mut Errors,
     config: &Config,

ui_test/src/tests.rs

@@ -1,6 +1,6 @@
 use std::path::{Path, PathBuf};
 
-use ui_test::{check_annotations, Comments, Config, Error, Mode, OutputConflictHandling};
+use super::{check_annotations, Comments, Config, Error, Mode, OutputConflictHandling};
 
 fn config() -> Config {
     Config {