Extern crate

CHANGELOG.md

@@ -148,6 +148,7 @@ The following is a summary of the changes that may require your attention when u
   [#2926](https://github.com/rust-lang/mdBook/pull/2926)
 - Hide the sidebar resize indicator when JS isn't available.
   [#2923](https://github.com/rust-lang/mdBook/pull/2923)
+- Allow doctests to use external crates by referencing a `Cargo.toml`
 
 ## mdBook 0.5.0-beta.1
 [v0.5.0-alpha.1...v0.5.0-beta.1](https://github.com/rust-lang/mdBook/compare/v0.5.0-alpha.1...v0.5.0-beta.1)

Cargo.toml

@@ -27,6 +27,7 @@ rust-version = "1.88.0" # Keep in sync with installation.md and .github/workflow
 [workspace.dependencies]
 anyhow = "1.0.100"
 axum = "0.8.6"
+cargo-manifest = "0.19.1"
 clap = { version = "4.5.51", features = ["cargo", "wrap_help"] }
 clap_complete = "4.5.60"
 ego-tree = "0.10.0"
@@ -75,7 +76,7 @@ version = "0.5.0-beta.2"
 authors = [
     "Mathieu David <mathieudavid@mathieudavid.org>",
     "Michael-F-Bryan <michaelfbryan@gmail.com>",
-    "Matt Ickstadt <mattico8@gmail.com>"
+    "Matt Ickstadt <mattico8@gmail.com>",
 ]
 documentation = "https://rust-lang.github.io/mdBook/index.html"
 edition.workspace = true

crates/mdbook-core/Cargo.toml

@@ -9,6 +9,7 @@ rust-version.workspace = true
 
 [dependencies]
 anyhow.workspace = true
+cargo-manifest.workspace = true
 regex.workspace = true
 serde.workspace = true
 serde_json.workspace = true

crates/mdbook-core/src/config.rs

@@ -407,6 +407,8 @@ impl Default for BuildConfig {
 #[serde(default, rename_all = "kebab-case", deny_unknown_fields)]
 #[non_exhaustive]
 pub struct RustConfig {
+    /// Path to a Cargo.toml
+    pub manifest: Option<PathBuf>,
     /// Rust edition used in playground
     pub edition: Option<RustEdition>,
 }
@@ -737,6 +739,9 @@ mod tests {
         create-missing = false
         use-default-preprocessors = true
 
+        [rust]
+        manifest = "./Cargo.toml"
+
         [output.html]
         theme = "./themedir"
         default-theme = "rust"
@@ -775,7 +780,10 @@ mod tests {
             use_default_preprocessors: true,
             extra_watch_dirs: Vec::new(),
         };
-        let rust_should_be = RustConfig { edition: None };
+        let rust_should_be = RustConfig {
+            manifest: Some(PathBuf::from("./Cargo.toml")),
+            edition: None,
+        };
         let playground_should_be = Playground {
             editable: true,
             copyable: true,
@@ -853,6 +861,7 @@ mod tests {
         assert_eq!(got.book, book_should_be);
 
         let rust_should_be = RustConfig {
+            manifest: None,
             edition: Some(RustEdition::E2015),
         };
         let got = Config::from_str(src).unwrap();
@@ -872,6 +881,7 @@ mod tests {
         "#;
 
         let rust_should_be = RustConfig {
+            manifest: None,
             edition: Some(RustEdition::E2018),
         };
 
@@ -892,6 +902,7 @@ mod tests {
         "#;
 
         let rust_should_be = RustConfig {
+            manifest: None,
             edition: Some(RustEdition::E2021),
         };
 
@@ -1179,6 +1190,19 @@ mod tests {
         );
     }
 
+    /* todo -- make this test fail, as it should
+    #[test]
+    #[should_panic(expected = "Invalid configuration file")]
+    // invalid key in config file should really generate an error...
+    fn invalid_rust_setting() {
+        let src = r#"
+        [rust]
+        foo = "bar"
+        "#;
+
+        Config::from_str(src).unwrap();
+    }
+    */
     #[test]
     fn contains_key() {
         let src = r#"