Configure WASM tests an try isatty on wasi

.cargo/config.toml

@@ -0,0 +1,2 @@
+[target.wasm32-wasi]
+runner = ["./scripts/wasmtime-wrapper.sh"]

.github/workflows/ci.yml

@@ -80,12 +80,12 @@ jobs:
         env: 
           CARGO_BUILD_TARGET: ${{ matrix.target }}
         run: make test
-  wasm:
-    name: Wasm
+  wasm-check:
+    name: WASM Check
     strategy:
       fail-fast: false
       matrix:
-          target: [wasm32-unknown-unknown, wasm32-wasi]
+        target: [wasm32-unknown-unknown]
     runs-on: ubuntu-latest
     steps:
       - name: Install rust
@@ -101,6 +101,33 @@ jobs:
         env:
           CARGO_BUILD_TARGET: ${{ matrix.target }}
         run: make check
+  wasi:
+    name: WASI
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [wasm32-wasi]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          target: ${{ matrix.target }}
+          override: true
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Install WasmTime
+        run: |
+          curl https://wasmtime.dev/install.sh -sSf | bash
+          curl -LO https://github.com/bytecodealliance/wasmtime/releases/download/v4.0.0/wasmtime-v4.0.0-x86_64-linux.tar.xz
+          tar xvf wasmtime-v4.0.0-x86_64-linux.tar.xz
+          echo `pwd`/wasmtime-v4.0.0-x86_64-linux >> $GITHUB_PATH
+      - name: Test
+        env:
+          CARGO_BUILD_TARGET: ${{ matrix.target }}
+        run: make test
   nightly:
     name: Nightly Tests
     runs-on: ubuntu-latest

Cargo.toml

@@ -35,7 +35,8 @@ features = [
 ]
 
 [dev-dependencies]
-proptest = "1.0.0"
+# Pick a setup for proptest that works with wasi
+proptest = { version = "1.0.0", default-features = false, features = ["std", "bit-set", "break-dead-code"] }
 regex = "1.4.2"
 
 ## These are currently disabled.  If you want to play around with the benchmarks

scripts/wasmtime-wrapper.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+cd $SCRIPT_DIR/..
+wasmtime run --env INSTA_WORKSPACE_ROOT=/ --mapdir "/::$(pwd)" -- "$@"

src/wasm_term.rs

@@ -10,11 +10,20 @@ pub const DEFAULT_WIDTH: u16 = 80;
 
 #[inline]
 pub fn is_a_terminal(_out: &Term) -> bool {
-    false
+    #[cfg(target = "wasm32-wasi")]
+    {
+        unsafe { libc::isatty(out.as_raw_fd()) != 0 }
+    }
+    #[cfg(not(target = "wasm32-wasi"))]
+    {
+        false
+    }
 }
 
 #[inline]
 pub fn is_a_color_terminal(_out: &Term) -> bool {
+    // We currently never report color terminals.  For discussion see
+    // the issue in the WASI repo: https://github.com/WebAssembly/WASI/issues/162
     false
 }