remove serde kebab-case renaming for AdmonitionDefaults struct

src/book_config.rs

@@ -23,7 +23,7 @@ pub(crate) fn admonish_config_from_str(data: &str) -> Result<Config> {
     toml::from_str(data).context("Invalid mdbook-admonish configuration in book.toml")
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize, Default)]
 pub(crate) struct Config {
     #[serde(default)]
     pub on_failure: OnFailure,
@@ -86,3 +86,89 @@ impl Default for OnFailure {
         Self::Continue
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use pretty_assertions::assert_eq;
+
+    #[test]
+    fn empty_config_okay() -> Result<()> {
+        let actual = admonish_config_from_str("")?;
+        let expected = Config::default();
+        assert_eq!(actual, expected);
+        Ok(())
+    }
+
+    #[test]
+    fn css_id_prefix_kebab_case_allowed() -> Result<()> {
+        let expected = Config {
+            default: AdmonitionDefaults {
+                css_id_prefix: Some("flam-".to_owned()),
+                ..Default::default()
+            },
+            ..Default::default()
+        };
+
+        // Snake case okay
+        let actual = admonish_config_from_str(r#"default = { css_id_prefix = "flam-" }"#)?;
+        assert_eq!(actual, expected);
+
+        // Kebab case back-compat okay
+        let actual = admonish_config_from_str(r#"default = { css-id-prefix = "flam-" }"#)?;
+        assert_eq!(actual, expected);
+        Ok(())
+    }
+
+    #[test]
+    fn full_config_roundtrip() -> Result<()> {
+        let input = Config {
+            default: AdmonitionDefaults {
+                css_id_prefix: Some("flam-".to_owned()),
+                collapsible: true,
+                title: Some("".to_owned()),
+            },
+            assets_version: Some("1.1.1".to_owned()),
+            custom: vec![CustomDirective {
+                directive: "test-directive".to_owned(),
+                icon: PathBuf::from("/tmp/test-directive.svg"),
+                color: hex_color::HexColor::from((155, 79, 150)),
+                aliases: vec!["test-directive-alias-0".to_owned()],
+                title: Some("test-directive-title".to_owned()),
+            }],
+            on_failure: OnFailure::Bail,
+            renderer: HashMap::from([(
+                "test-mode".to_owned(),
+                RendererConfig {
+                    render_mode: Some(RenderMode::Strip),
+                },
+            )]),
+        };
+
+        let expected = r##"on_failure = "bail"
+assets_version = "1.1.1"
+
+[default]
+title = ""
+collapsible = true
+css_id_prefix = "flam-"
+
+[renderer.test-mode]
+render_mode = "strip"
+
+[[custom]]
+directive = "test-directive"
+icon = "/tmp/test-directive.svg"
+color = "#9B4F96"
+aliases = ["test-directive-alias-0"]
+title = "test-directive-title"
+"##;
+
+        let serialized = toml::to_string(&input)?;
+        assert_eq!(serialized, expected);
+
+        let actual = admonish_config_from_str(&serialized)?;
+        assert_eq!(actual, input);
+        Ok(())
+    }
+}

src/types.rs

@@ -5,7 +5,6 @@ use std::str::FromStr;
 
 /// Book wide defaults that may be provided by the user.
 #[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize, Default)]
-#[serde(rename_all = "kebab-case")]
 pub(crate) struct AdmonitionDefaults {
     #[serde(default)]
     pub(crate) title: Option<String>,
@@ -14,6 +13,9 @@ pub(crate) struct AdmonitionDefaults {
     pub(crate) collapsible: bool,
 
     #[serde(default)]
+    // For backwards compatibility, we support this field with kebab-case style
+    // naming, even though this was introduced in error.
+    #[serde(alias = "css-id-prefix")]
     pub(crate) css_id_prefix: Option<String>,
 }