added wasm-pack feature checking wasm-pack version

src/build.rs

@@ -4,6 +4,7 @@ use child;
 use emoji;
 use error::Error;
 use failure::ResultExt;
+use manifest::Crate;
 use progressbar::Step;
 use slog::Logger;
 use std::path::Path;
@@ -36,6 +37,26 @@ pub fn check_rustc_version(step: &Step) -> Result<String, failure::Error> {
     }
 }
 
+/// Checks if `wasm-pack` is updated to the latest version
+pub fn check_wasm_pack_version(step: &Step) -> Result<(), failure::Error> {
+    let msg = format!("{}Checking `wasm-pack` version...", emoji::PACKAGE);
+    PBAR.step(step, &msg);
+    let wasm_pack_local_version = wasm_pack_local_version();
+    let wasm_pack_latest_version = Crate::return_wasm_pack_latest_version();
+    match wasm_pack_local_version {
+        Some(lv) => {
+            if !(lv == wasm_pack_latest_version) {
+                Ok(PBAR.info(&format!("There's a newer version of wasm-pack available, the new version is: {}, you are using: {}", wasm_pack_latest_version, lv)))
+            } else {
+                Ok(())
+            }
+        },
+        None => Err(Error::WasmPackMissing {
+            message: "We can't figure out what your wasm-pack version is, make sure the installation path is correct.".to_string(),
+        }.into()),
+    }
+}
+
 // from https://github.com/alexcrichton/proc-macro2/blob/79e40a113b51836f33214c6d00228934b41bd4ad/build.rs#L44-L61
 fn rustc_minor_version() -> Option<u32> {
     macro_rules! otry {
@@ -55,6 +76,29 @@ fn rustc_minor_version() -> Option<u32> {
     otry!(pieces.next()).parse().ok()
 }
 
+fn wasm_pack_local_version() -> Option<String> {
+    macro_rules! otry {
+        ($e:expr) => {
+            match $e {
+                Some(e) => e,
+                None => return None,
+            }
+        };
+    }
+
+    let output = otry!(Command::new("wasm-pack").arg("--version").output().ok());
+    let version = otry!(str::from_utf8(&output.stdout).ok());
+    let mut pieces = version.split(' ');
+    if pieces.next() != Some("wasm-pack") {
+        return None;
+    }
+    otry!(pieces.next())
+        .to_string()
+        .trim()
+        .parse::<String>()
+        .ok()
+}
+
 /// Ensure that `rustup` has the `wasm32-unknown-unknown` target installed for
 /// current toolchain
 pub fn rustup_add_wasm_target(log: &Logger, step: &Step) -> Result<(), failure::Error> {

src/command/build.rs

@@ -160,6 +160,7 @@ impl Build {
         match &mode {
             BuildMode::Normal => steps![
                 step_check_rustc_version,
+                step_check_wasm_pack_version,
                 step_check_crate_config,
                 step_add_wasm_target,
                 step_build_wasm,
@@ -171,6 +172,7 @@ impl Build {
             ],
             BuildMode::Noinstall => steps![
                 step_check_rustc_version,
+                step_check_wasm_pack_version,
                 step_check_crate_config,
                 step_build_wasm,
                 step_create_dir,
@@ -200,6 +202,18 @@ impl Build {
         Ok(())
     }
 
+    fn step_check_wasm_pack_version(
+        &mut self,
+        step: &Step,
+        log: &Logger,
+    ) -> Result<(), failure::Error> {
+        info!(&log, "Checking wasm-pack version...");
+        let version = build::check_wasm_pack_version(step)?;
+        let msg = format!("wasm-pack version is: {:?}.", version);
+        info!(&log, "{}", &msg);
+        Ok(())
+    }
+
     fn step_check_crate_config(&mut self, step: &Step, log: &Logger) -> Result<(), failure::Error> {
         info!(&log, "Checking crate configuration...");
         manifest::check_crate_config(&self.crate_path, step)?;

src/error.rs

@@ -46,6 +46,24 @@ pub enum Error {
         local_minor_version: String,
     },
 
+    #[fail(display = "{}", _0)]
+    /// An error in parsing your wasm-pack version.
+    WasmPackMissing {
+        /// Error message
+        message: String,
+    },
+
+    #[fail(display = "{}", _0)]
+    /// An error from having an older wasm-pack version.
+    WasmPackVersion {
+        /// Error message
+        message: String,
+        /// Local version of wasm-pack
+        local_version: String,
+        /// Latest version of wasm-pack
+        latest_version: String,
+    },
+
     /// An error invoking another CLI tool.
     #[fail(
         display = "Process exited with {}: {}.\n\nstdout:{}\n\nstderr:\n\n{}",
@@ -163,6 +181,14 @@ impl Error {
               message: _,
               local_minor_version: _,
             } => "Your rustc version is not supported. Please install version 1.30.0 or higher.",
+            Error::WasmPackMissing {
+                message: _,
+            } => "We can't figure out what your wasm-pack version is, make sure the installation path is correct.",
+            Error::WasmPackVersion {
+                message: _,
+                local_version: _,
+                latest_version: _,
+            } => "There's a newer version of wasm-pack available, the new version is: , you are using: ",
             Error::Cli {
                 message: _,
                 stdout: _,

src/manifest/mod.rs

@@ -10,14 +10,25 @@ use std::path::Path;
 use self::npm::{
     repository::Repository, CommonJSPackage, ESModulesPackage, NoModulesPackage, NpmPackage,
 };
+use curl::easy;
 use emoji;
 use error::Error;
 use failure;
 use progressbar::Step;
 use serde_json;
 use toml;
+
 use PBAR;
 
+struct Collector(Vec<u8>);
+
+impl easy::Handler for Collector {
+    fn write(&mut self, data: &[u8]) -> Result<usize, easy::WriteError> {
+        self.0.extend_from_slice(data);
+        Ok(data.len())
+    }
+}
+
 #[derive(Debug, Deserialize)]
 struct CargoManifest {
     package: CargoPackage,
@@ -77,6 +88,39 @@ struct CargoLib {
     crate_type: Option<Vec<String>>,
 }
 
+/// Struct for crates.io api, currently checking wasm-pack latest version
+#[derive(Deserialize, Debug)]
+pub struct Crate {
+    #[serde(rename = "crate")]
+    crt: CrateInformation,
+}
+
+#[derive(Deserialize, Debug)]
+struct CrateInformation {
+    max_version: String,
+}
+
+impl Crate {
+    /// Call to the crates.io api and return the latest version of `wasm-pack`
+    pub fn return_wasm_pack_latest_version() -> String {
+        let crt = Crate::check_wasm_pack_latest_version();
+        crt.crt.max_version
+    }
+
+    fn check_wasm_pack_latest_version() -> Crate {
+        let mut easy = easy::Easy2::new(Collector(Vec::new()));
+        easy.get(true).unwrap();
+        easy.url("https://crates.io/api/v1/crates/wasm-pack")
+            .unwrap();
+        easy.perform().unwrap();
+
+        let contents = easy.get_ref();
+        let result = String::from_utf8_lossy(&contents.0);
+
+        serde_json::from_str(result.into_owned().as_str()).unwrap()
+    }
+}
+
 fn read_cargo_toml(path: &Path) -> Result<CargoManifest, failure::Error> {
     let manifest_path = path.join("Cargo.toml");
     if !manifest_path.is_file() {