feat: adds candid-wasm-bindgen library for npm

Cargo.toml

@@ -4,4 +4,5 @@ members = [
     "rust/candid_derive",
     "tools/candiff",
     "tools/didc",
+    "tools/candid-wasm-bindgen"
 ]

rust/candid/src/parser/typing.rs

@@ -3,6 +3,7 @@ use crate::types::{Field, Function, Type};
 use crate::{pretty_parse, Error, Result};
 use std::collections::{BTreeMap, BTreeSet};
 use std::path::{Path, PathBuf};
+use std::str;
 
 pub struct Env<'a> {
     pub te: &'a mut TypeEnv,
@@ -408,13 +409,18 @@ fn check_file_(file: &Path, is_pretty: bool) -> Result<(TypeEnv, Option<Type>)>
     };
     let prog = std::fs::read_to_string(&file)
         .map_err(|_| Error::msg(format!("Cannot open {:?}", file)))?;
+
+    check_str(&prog, is_pretty, &base)
+}
+
+pub fn check_str(str: &str, is_pretty: bool, base: &Path) -> Result<(TypeEnv, Option<Type>)> {
     let prog = if is_pretty {
-        pretty_parse::<IDLProg>(file.to_str().unwrap(), &prog)?
+        pretty_parse::<IDLProg>("tmp.did", str)?
     } else {
-        prog.parse::<IDLProg>()?
+        str.parse::<IDLProg>()?
     };
     let mut imports = Vec::new();
-    load_imports(is_pretty, &base, &mut BTreeSet::new(), &prog, &mut imports)?;
+    load_imports(is_pretty, base, &mut BTreeSet::new(), &prog, &mut imports)?;
     let mut te = TypeEnv::new();
     let mut env = Env {
         te: &mut te,

tools/candid-wasm-bindgen/.appveyor.yml

@@ -0,0 +1,11 @@
+install:
+  - appveyor-retry appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
+  - if not defined RUSTFLAGS rustup-init.exe -y --default-host x86_64-pc-windows-msvc --default-toolchain nightly
+  - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
+  - rustc -V
+  - cargo -V
+
+build: false
+
+test_script:
+  - cargo test --locked

tools/candid-wasm-bindgen/.gitignore

@@ -0,0 +1,7 @@
+/target
+**/*.rs.bk
+Cargo.lock
+bin/
+pkg/
+wasm-pack.log
+node_modules

tools/candid-wasm-bindgen/.travis.yml

@@ -0,0 +1,69 @@
+language: rust
+sudo: false
+
+cache: cargo
+
+matrix:
+  include:
+
+  # Builds with wasm-pack.
+  - rust: beta
+    env: RUST_BACKTRACE=1
+    addons:
+      firefox: latest
+      chrome: stable
+    before_script:
+      - (test -x $HOME/.cargo/bin/cargo-install-update || cargo install cargo-update)
+      - (test -x $HOME/.cargo/bin/cargo-generate || cargo install --vers "^0.2" cargo-generate)
+      - cargo install-update -a
+      - curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh -s -- -f
+    script:
+      - cargo generate --git . --name testing
+      # Having a broken Cargo.toml (in that it has curlies in fields) anywhere
+      # in any of our parent dirs is problematic.
+      - mv Cargo.toml Cargo.toml.tmpl
+      - cd testing
+      - wasm-pack build
+      - wasm-pack test --chrome --firefox --headless
+
+  # Builds on nightly.
+  - rust: nightly
+    env: RUST_BACKTRACE=1
+    before_script:
+      - (test -x $HOME/.cargo/bin/cargo-install-update || cargo install cargo-update)
+      - (test -x $HOME/.cargo/bin/cargo-generate || cargo install --vers "^0.2" cargo-generate)
+      - cargo install-update -a
+      - rustup target add wasm32-unknown-unknown
+    script:
+      - cargo generate --git . --name testing
+      - mv Cargo.toml Cargo.toml.tmpl
+      - cd testing
+      - cargo check
+      - cargo check --target wasm32-unknown-unknown
+      - cargo check                                 --no-default-features
+      - cargo check --target wasm32-unknown-unknown --no-default-features
+      - cargo check                                 --no-default-features --features console_error_panic_hook
+      - cargo check --target wasm32-unknown-unknown --no-default-features --features console_error_panic_hook
+      - cargo check                                 --no-default-features --features "console_error_panic_hook wee_alloc"
+      - cargo check --target wasm32-unknown-unknown --no-default-features --features "console_error_panic_hook wee_alloc"
+
+  # Builds on beta.
+  - rust: beta
+    env: RUST_BACKTRACE=1
+    before_script:
+      - (test -x $HOME/.cargo/bin/cargo-install-update || cargo install cargo-update)
+      - (test -x $HOME/.cargo/bin/cargo-generate || cargo install --vers "^0.2" cargo-generate)
+      - cargo install-update -a
+      - rustup target add wasm32-unknown-unknown
+    script:
+      - cargo generate --git . --name testing
+      - mv Cargo.toml Cargo.toml.tmpl
+      - cd testing
+      - cargo check
+      - cargo check --target wasm32-unknown-unknown
+      - cargo check                                 --no-default-features
+      - cargo check --target wasm32-unknown-unknown --no-default-features
+      - cargo check                                 --no-default-features --features console_error_panic_hook
+      - cargo check --target wasm32-unknown-unknown --no-default-features --features console_error_panic_hook
+      # Note: no enabling the `wee_alloc` feature here because it requires
+      # nightly for now.

tools/candid-wasm-bindgen/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "candid-wasm-bindgen"
+version = "0.1.0"
+authors = ["Kyle Peacock <kylpeacock@gmail.com>"]
+edition = "2018"
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[features]
+default = ["console_error_panic_hook"]
+
+[dependencies]
+wasm-bindgen = "0.2.63"
+candid = { path = "../../rust/candid" }
+
+# The `console_error_panic_hook` crate provides better debugging of panics by
+# logging them with `console.error`. This is great for development, but requires
+# all the `std::fmt` and `std::panicking` infrastructure, so isn't great for
+# code size when deploying.
+console_error_panic_hook = { version = "0.1.6", optional = true }
+
+[dev-dependencies]
+wasm-bindgen-test = "0.3.13"
+
+[profile.release]
+# Tell `rustc` to optimize for small code size.
+opt-level = "s"