add support for building examples

src/cmd/build.rs

@@ -82,6 +82,10 @@ pub struct Build {
     #[arg(default_missing_value="true", num_args=0..=1)]
     pub filehash: Option<bool>,
 
+    /// Which example to build
+    #[arg(long, env = "TRUNK_BUILD_EXAMPLE")]
+    pub example: Option<String>,
+
     /// When desired, set a custom root certificate chain (same format as Cargo's config.toml http.cainfo)
     #[arg(long, env = "TRUNK_BUILD_ROOT_CERTIFICATE")]
     pub root_certificate: Option<String>,
@@ -140,6 +144,7 @@ impl Build {
             all_features,
             features,
             filehash,
+            example,
             root_certificate,
             accept_invalid_certs,
             minify,
@@ -166,6 +171,7 @@ impl Build {
         config.build.features = features.unwrap_or(config.build.features);
 
         config.build.filehash = filehash.unwrap_or(config.build.filehash);
+        config.build.example = example.or(config.build.example);
 
         config.build.root_certificate = root_certificate.or(config.build.root_certificate);
         config.build.accept_invalid_certs =

src/config/models/build.rs

@@ -76,6 +76,11 @@ pub struct Build {
     #[serde(default = "default::filehash")]
     pub filehash: bool,
 
+    /// Whether to build an example.
+    #[serde(default)]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub example: Option<String>,
+
     /// Optional pattern for the app loader script [default: None]
     ///
     /// Patterns should include the sequences `{base}`, `{wasm}`, and `{js}` in order to
@@ -214,6 +219,7 @@ impl Default for Build {
             no_default_features: false,
             all_features: false,
             features: vec![],
+            example: None,
             filehash: default::filehash(),
             pattern_script: None,
             inject_scripts: default::inject_scripts(),

src/config/rt/build.rs

@@ -56,6 +56,8 @@ pub struct RtcBuild {
     pub staging_dist: PathBuf,
     /// The configuration of the features passed to cargo.
     pub cargo_features: Features,
+    /// Optional example to be passed to cargo.
+    pub cargo_example: Option<String>,
     /// Configuration for automatic application download.
     pub tools: Tools,
     /// Build process hooks.
@@ -202,6 +204,7 @@ impl RtcBuild {
             staging_dist,
             final_dist,
             cargo_features,
+            cargo_example: build.example,
             tools,
             hooks,
             inject_autoloader,
@@ -246,6 +249,7 @@ impl RtcBuild {
             final_dist,
             staging_dist,
             cargo_features: Features::All,
+            cargo_example: None,
             tools: Default::default(),
             hooks: Vec::new(),
             inject_autoloader: true,

src/pipelines/rust/mod.rs

@@ -420,6 +420,10 @@ impl RustApp {
             args.push("--bin");
             args.push(bin);
         }
+        if let Some(example) = &self.cfg.cargo_example {
+            args.push("--example");
+            args.push(example);
+        }
 
         match &self.cargo_features {
             Features::All => args.push("--all-features"),
@@ -818,13 +822,22 @@ impl RustApp {
             return false;
         }
 
-        // must be cdylib or bin
+        // must be cdylib, bin, or example
         if !(art.target.kind.contains(&"bin".to_string())
-            || art.target.kind.contains(&"cdylib".to_string()))
+            || art.target.kind.contains(&"cdylib".to_string())
+            || art.target.kind.contains(&"example".to_string()))
         {
             return false;
         }
 
+        // Are we building an example?
+        if let Some(example) = &self.cfg.cargo_example {
+            // it must match
+            if example != &art.target.name {
+                return false;
+            }
+        }
+
         // if we have the --bin argument
         if let Some(bin) = &self.bin {
             // it must match