bindgen.rs

//! Functionality related to running `wasm-bindgen`.

use crate::child;
use crate::command::build::{BuildProfile, Target};
use crate::install::{self, Tool};
use crate::manifest::CrateData;
use anyhow::{bail, Context, Result};
use semver;
use std::path::Path;
use std::process::Command;

/// Run the `wasm-bindgen` CLI to generate bindings for the current crate's
/// `.wasm`.
pub fn wasm_bindgen_build(
    data: &CrateData,
    install_status: &install::Status,
    out_dir: &Path,
    out_name: &Option<String>,
    disable_dts: bool,
    weak_refs: bool,
    reference_types: bool,
    target: Target,
    profile: BuildProfile,
    extra_options: &Vec<String>,
) -> Result<()> {
    let profile_name = match profile.clone() {
        BuildProfile::Release | BuildProfile::Profiling => "release",
        BuildProfile::Dev => "debug",
        BuildProfile::Custom(profile_name) => &profile_name.clone(),
    };

    let out_dir = out_dir.to_str().unwrap();

    let target_directory = {
        let mut has_target_dir_iter = extra_options.iter();
        has_target_dir_iter
            .find(|&it| it == "--target-dir")
            .and_then(|_| has_target_dir_iter.next())
            .map(Path::new)
            .unwrap_or(data.target_directory())
    };

    let wasm_path = target_directory
        .join("wasm32-unknown-unknown")
        .join(profile_name)
        .join(data.crate_name())
        .with_extension("wasm");

    let dts_arg = if disable_dts {
        "--no-typescript"
    } else {
        "--typescript"
    };
    let bindgen_path = install::get_tool_path(install_status, Tool::WasmBindgen)?
        .binary(&Tool::WasmBindgen.to_string())?;

    let mut cmd = Command::new(&bindgen_path);
    cmd.arg(&wasm_path)
        .arg("--out-dir")
        .arg(out_dir)
        .arg(dts_arg);

    if weak_refs {
        cmd.arg("--weak-refs");
    }

    if reference_types {
        cmd.arg("--reference-types");
    }

    let target_arg = build_target_arg(target, &bindgen_path)?;
    if supports_dash_dash_target(&bindgen_path)? {
        cmd.arg("--target").arg(target_arg);
    } else {
        cmd.arg(target_arg);
    }

    if let Some(value) = out_name {
        cmd.arg("--out-name").arg(value);
    }

    let profile = data.configured_profile(profile);
    if profile.wasm_bindgen_debug_js_glue() {
        cmd.arg("--debug");
    }
    if !profile.wasm_bindgen_demangle_name_section() {
        cmd.arg("--no-demangle");
    }
    if profile.wasm_bindgen_dwarf_debug_info() {
        cmd.arg("--keep-debug");
    }
    if profile.wasm_bindgen_omit_default_module_path() {
        cmd.arg("--omit-default-module-path");
    }

    child::run(cmd, "wasm-bindgen").context("Running the wasm-bindgen CLI")?;
    Ok(())
}

/// Check if the `wasm-bindgen` dependency is locally satisfied for the web target
fn supports_web_target(cli_path: &Path) -> Result<bool> {
    let cli_version = semver::Version::parse(&install::get_cli_version(
        &install::Tool::WasmBindgen,
        cli_path,
    )?)?;
    let expected_version = semver::Version::parse("0.2.39")?;
    Ok(cli_version >= expected_version)
}

/// Check if the `wasm-bindgen` dependency is locally satisfied for the --target flag
fn supports_dash_dash_target(cli_path: &Path) -> Result<bool> {
    let cli_version = semver::Version::parse(&install::get_cli_version(
        &install::Tool::WasmBindgen,
        cli_path,
    )?)?;
    let expected_version = semver::Version::parse("0.2.40")?;
    Ok(cli_version >= expected_version)
}

fn build_target_arg(target: Target, cli_path: &Path) -> Result<String> {
    if !supports_dash_dash_target(cli_path)? {
        Ok(build_target_arg_legacy(target, cli_path)?)
    } else {
        Ok(target.to_string())
    }
}

fn build_target_arg_legacy(target: Target, cli_path: &Path) -> Result<String> {
    log::info!("Your version of wasm-bindgen is out of date. You should consider updating your Cargo.toml to a version >= 0.2.40.");
    let target_arg = match target {
        Target::Nodejs => "--nodejs",
        Target::NoModules => "--no-modules",
        Target::Web => {
            if supports_web_target(cli_path)? {
                "--web"
            } else {
                bail!("Your current version of wasm-bindgen does not support the 'web' target. Please update your project to wasm-bindgen version >= 0.2.39.")
            }
        }
        Target::Bundler => "--browser",
        Target::Deno => "--deno",
    };
    Ok(target_arg.to_string())
}