Solves rustwasm#146. Check locally installed wasm-bindgen dependency.

src/bindgen.rs

@@ -1,24 +1,67 @@
 use emoji;
 use error::Error;
 use progressbar::Step;
-use std::process::Command;
+use std::{path, process::Command};
 use PBAR;
 
-pub fn cargo_install_wasm_bindgen(step: &Step) -> Result<(), Error> {
+#[cfg(not(target_family = "windows"))]
+static LOCAL_BINDGEN_PATH: &str = "bin/wasm-bindgen";
+
+#[cfg(target_family = "windows")]
+static LOCAL_BINDGEN_PATH: &str = "bin\\wasm-bindgen";
+
+fn local_wasm_bindgen_path_str(crate_path: &str) -> String {
+    #[cfg(not(target_family = "windows"))]
+    return format!("{}/{}", crate_path, LOCAL_BINDGEN_PATH);
+    #[cfg(target_family = "windows")]
+    return format!("{}\\{}", crate_path, LOCAL_BINDGEN_PATH);
+}
+
+pub fn wasm_bindgen_version_check(
+    crate_path: &str,
+    dep_version: &str,
+    step: &Step,
+) -> Result<bool, Error> {
+    let msg = format!("{}Checking WASM-bindgen dependency...", emoji::CHECK);
+    PBAR.step(step, &msg);
+
+    let wasm_bindgen = local_wasm_bindgen_path_str(crate_path);
+    if !path::Path::new(&wasm_bindgen).is_file() {
+        return Ok(false);
+    }
+
+    let output = Command::new(wasm_bindgen).arg("--version").output()?;
+    if output.status.success() {
+        let s = String::from_utf8_lossy(&output.stdout);
+        let installed_version = s.trim();
+        Ok(installed_version == dep_version)
+    } else {
+        let error_msg = "Could not find version of local wasm-bindgen";
+        let s = String::from_utf8_lossy(&output.stderr);
+        let e = Error::cli(error_msg, s);
+        Err(e)
+    }
+}
+
+pub fn cargo_install_wasm_bindgen(path: &str, version: &str, step: &Step) -> Result<(), Error> {
     let msg = format!("{}Installing WASM-bindgen...", emoji::DOWN_ARROW);
     PBAR.step(step, &msg);
     let output = Command::new("cargo")
         .arg("install")
-        .arg("wasm-bindgen-cli")
         .arg("--force")
+        .arg("wasm-bindgen-cli")
+        .arg("--version")
+        .arg(version)
+        .arg("--root")
+        .arg(path)
         .output()?;
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
         if s.contains("already exists") {
             PBAR.info("wasm-bindgen already installed");
             return Ok(());
         }
-        Error::cli("Installing wasm-bindgen failed", s)
+        Err(Error::cli("Installing wasm-bindgen failed", s))
     } else {
         Ok(())
     }
@@ -51,7 +94,8 @@ pub fn wasm_bindgen_build(
         _ => "--browser",
     };
 
-    let output = Command::new("wasm-bindgen")
+    let wasm_bindgen = local_wasm_bindgen_path_str(path);
+    let output = Command::new(wasm_bindgen)
         .current_dir(path)
         .arg(&wasm_path)
         .arg("--out-dir")
@@ -61,7 +105,7 @@ pub fn wasm_bindgen_build(
         .output()?;
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli("wasm-bindgen failed to execute properly", s)
+        Err(Error::cli("wasm-bindgen failed to execute properly", s))
     } else {
         Ok(())
     }

src/build.rs

@@ -17,7 +17,10 @@ pub fn rustup_add_wasm_target(step: &Step) -> Result<(), Error> {
         .output()?;
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli("Adding the wasm32-unknown-unknown target failed", s)
+        Err(Error::cli(
+            "Adding the wasm32-unknown-unknown target failed",
+            s,
+        ))
     } else {
         Ok(())
     }
@@ -33,7 +36,7 @@ fn ensure_nightly() -> Result<(), Error> {
             .output()?;
         if !res.status.success() {
             let s = String::from_utf8_lossy(&res.stderr);
-            return Error::cli("Adding the nightly toolchain failed", s);
+            return Err(Error::cli("Adding the nightly toolchain failed", s));
         }
     }
     Ok(())
@@ -54,7 +57,7 @@ pub fn cargo_build_wasm(path: &str, debug: bool, step: &Step) -> Result<(), Erro
 
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli("Compilation of your program failed", s)
+        Err(Error::cli("Compilation of your program failed", s))
     } else {
         Ok(())
     }

src/command/init.rs

@@ -192,9 +192,15 @@ impl Init {
     }
 
     fn step_install_wasm_bindgen(&mut self, step: &Step, log: &Logger) -> Result<(), Error> {
-        info!(&log, "Installing wasm-bindgen-cli...");
-        bindgen::cargo_install_wasm_bindgen(step)?;
-        info!(&log, "Installing wasm-bindgen-cli was successful.");
+        info!(&log, "Checking WASM-bindgen version...");
+        let bindgen_version = manifest::get_wasm_bindgen_version(&self.crate_path)?;
+        let bindgen_installed =
+            bindgen::wasm_bindgen_version_check(&self.crate_path, &bindgen_version, step)?;
+        if !bindgen_installed {
+            info!(&log, "Installing wasm-bindgen-cli...");
+            bindgen::cargo_install_wasm_bindgen(&self.crate_path, &bindgen_version, step)?;
+            info!(&log, "Installing wasm-bindgen-cli was successful.");
+        }
 
         info!(&log, "Getting the crate name from the manifest...");
         self.crate_name = manifest::get_crate_name(&self.crate_path)?;

src/emoji.rs

@@ -13,3 +13,4 @@ pub static DANCERS: Emoji = Emoji("👯  ", "");
 pub static ERROR: Emoji = Emoji("⛔  ", "");
 pub static INFO: Emoji = Emoji("ℹ️  ", "");
 pub static WRENCH: Emoji = Emoji("🔧  ", "");
+pub static CHECK: Emoji = Emoji("✓  ", "");

src/error.rs

@@ -20,17 +20,17 @@ pub enum Error {
 }
 
 impl Error {
-    pub fn cli(message: &str, stderr: Cow<str>) -> Result<(), Self> {
-        Err(Error::Cli {
+    pub fn cli(message: &str, stderr: Cow<str>) -> Self {
+        Error::Cli {
             message: message.to_string(),
             stderr: stderr.to_string(),
-        })
+        }
     }
 
-    pub fn crate_config(message: &str) -> Result<(), Self> {
-        Err(Error::CrateConfig {
+    pub fn crate_config(message: &str) -> Self {
+        Error::CrateConfig {
             message: message.to_string(),
-        })
+        }
     }
 
     pub fn error_type(&self) -> String {

src/manifest.rs

@@ -148,6 +148,30 @@ pub fn get_crate_name(path: &str) -> Result<String, Error> {
     Ok(read_cargo_toml(path)?.package.name)
 }
 
+pub fn get_wasm_bindgen_version(path: &str) -> Result<String, Error> {
+    match read_cargo_toml(path)?
+        .dependencies
+        .and_then(|deps| deps.wasm_bindgen)
+    {
+        Some(ref version) if version.is_empty() => {
+            let msg = format!(
+                "\"{}\" dependency is missing its version number",
+                style("wasm-bindgen").bold().dim()
+            );
+            let e = Error::crate_config(&msg);
+            Err(e)
+        }
+        Some(version) => Ok(version),
+        None => {
+            let msg = format!(
+                "Ensure that you have \"{}\" as a dependency in your Cargo.toml file:\n[dependencies]\nwasm-bindgen = \"0.2\"",
+                style("wasm-bindgen").bold().dim());
+            let e = Error::crate_config(&msg);
+            Err(e)
+        }
+    }
+}
+
 pub fn check_crate_config(path: &str, step: &Step) -> Result<(), Error> {
     let msg = format!("{}Checking crate configuration...", emoji::WRENCH);
     PBAR.step(&step, &msg);
@@ -157,25 +181,19 @@ pub fn check_crate_config(path: &str, step: &Step) -> Result<(), Error> {
 }
 
 fn check_wasm_bindgen(path: &str) -> Result<(), Error> {
-    if read_cargo_toml(path)?.dependencies.map_or(false, |x| {
-        !x.wasm_bindgen.unwrap_or("".to_string()).is_empty()
-    }) {
-        return Ok(());
-    }
-    Error::crate_config(&format!(
-        "Ensure that you have \"{}\" as a dependency in your Cargo.toml file:\n[dependencies]\nwasm-bindgen = \"0.2\"",
-        style("wasm-bindgen").bold().dim()
-    ))
+    let _ = get_wasm_bindgen_version(path)?;
+    Ok(())
 }
 
 fn check_crate_type(path: &str) -> Result<(), Error> {
     if read_cargo_toml(path)?.lib.map_or(false, |lib| {
         lib.crate_type
             .map_or(false, |types| types.iter().any(|s| s == "cdylib"))
     }) {
-        return Ok(());
+        Ok(())
+    } else {
+        let msg = "crate-type must be cdylib to compile to wasm32-unknown-unknown. Add the following to your Cargo.toml file:\n\n[lib]\ncrate-type = [\"cdylib\"]";
+        let e = Error::crate_config(msg);
+        Err(e)
     }
-    Error::crate_config(
-      "crate-type must be cdylib to compile to wasm32-unknown-unknown. Add the following to your Cargo.toml file:\n\n[lib]\ncrate-type = [\"cdylib\"]"
-    )
 }

src/npm.rs

@@ -11,7 +11,7 @@ pub fn npm_pack(path: &str) -> Result<(), Error> {
         .output()?;
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli("Packaging up your code failed", s)
+        Err(Error::cli("Packaging up your code failed", s))
     } else {
         Ok(())
     }
@@ -25,7 +25,7 @@ pub fn npm_publish(path: &str) -> Result<(), Error> {
         .output()?;
     if !output.status.success() {
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli("Publishing to npm failed", s)
+        Err(Error::cli("Publishing to npm failed", s))
     } else {
         Ok(())
     }
@@ -61,8 +61,9 @@ pub fn npm_login(
         .output()?;
 
     if !output.status.success() {
+        let message = format!("Login to registry {} failed", registry);
         let s = String::from_utf8_lossy(&output.stderr);
-        Error::cli(&format!("Login to registry {} failed", registry), s)
+        Err(Error::cli(&message, s))
     } else {
         Ok(())
     }