new: Support help text. (#81)

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+#### 🚀 Updates
+
+- Added `ConfigLoader.set_help` to customize help text for validation errors.
+
 ## 0.12.10
 
 #### 🚀 Updates

Cargo.toml

@@ -14,5 +14,5 @@ serde_json = "1.0.108"
 serde_yaml = "0.9.27"
 toml = "0.8.8"
 url = "2.5.0"
-version_spec = "0.1.5"
-warpgate = "0.5.14"
+version_spec = "0.1.7"
+warpgate = "0.7.0"

crates/config/src/config/errors.rs

@@ -96,6 +96,9 @@ pub enum ConfigError {
         // #[diagnostic_source]
         #[source]
         error: ValidatorError,
+
+        #[help]
+        help: Option<String>,
     },
 }
 

crates/config/src/config/loader.rs

@@ -24,6 +24,7 @@ pub struct ConfigLoadResult<T: Config> {
 pub struct ConfigLoader<T: Config> {
     _config: PhantomData<T>,
     cacher: Mutex<BoxedCacher>,
+    help: Option<String>,
     sources: Vec<Source>,
     root: Option<PathBuf>,
 }
@@ -35,6 +36,7 @@ impl<T: Config> ConfigLoader<T> {
         ConfigLoader {
             _config: PhantomData,
             cacher: Mutex::new(Box::<MemoryCache>::default()),
+            help: None,
             sources: vec![],
             root: None,
         }
@@ -104,6 +106,7 @@ impl<T: Config> ConfigLoader<T> {
                     None => T::META.name.to_owned(),
                 },
                 error,
+                help: self.help.clone(),
             })?;
 
         Ok(ConfigLoadResult {
@@ -135,6 +138,12 @@ impl<T: Config> ConfigLoader<T> {
         self
     }
 
+    /// Set a string of help text to include in validation errors.
+    pub fn set_help<H: AsRef<str>>(&mut self, help: H) -> &mut Self {
+        self.help = Some(help.as_ref().to_owned());
+        self
+    }
+
     /// Set the project root directory, for use within error messages.
     pub fn set_root<P: AsRef<Path>>(&mut self, root: P) -> &mut Self {
         self.root = Some(root.as_ref().to_path_buf());
@@ -253,6 +262,7 @@ impl<T: Config> ConfigLoader<T> {
                 .map_err(|error| ConfigError::Validator {
                     config: location.to_owned(),
                     error,
+                    help: self.help.clone(),
                 })?;
 
             if let Some(extends_from) = partial.extends_from() {

crates/config/src/config/source.rs

@@ -102,7 +102,7 @@ impl Source {
     where
         D: DeserializeOwned,
     {
-        let handle_error = |error: crate::ParserError| ConfigError::Parser {
+        let handle_error = |error: crate::config::ParserError| ConfigError::Parser {
             config: location.to_owned(),
             error,
         };

crates/config/src/config/validator.rs

@@ -155,6 +155,8 @@ impl Display for ValidatorError {
             }
         }
 
+        writeln!(f)?;
+
         Ok(())
     }
 }

crates/test-app/src/main.rs

@@ -44,6 +44,7 @@ fn main() -> Result<()> {
         // .code(r#"{ "string": "abc", "other": 123 }"#, Format::Json)?
         // .code("{\n  \"string\": 123\n}", Format::Json)?
         .code("{\n  \"string\": \"\" \n}", Format::Json)?
+        .set_help("let's go!")
         .load()?;
 
     dbg!(&config.config.string);