Run miri in CI

.github/workflows/ci.yml

@@ -45,6 +45,24 @@ jobs:
       - name: Run tests
         run: cargo test --all --verbose --features fancy
 
+  miri:
+    name: Miri
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          components: miri,rust-src
+          override: true
+      - name: Run tests with miri
+        env:
+          MIRIFLAGS: -Zmiri-disable-isolation -Zmiri-strict-provenance
+        run: cargo miri test --all --verbose --features fancy
+
   minimal_versions:
     name: Minimal versions check
     runs-on: ${{ matrix.os }}

src/handler.rs

@@ -261,6 +261,7 @@ impl MietteHandlerOpts {
         }
     }
 
+    #[cfg(not(miri))]
     pub(crate) fn get_width(&self) -> usize {
         self.width.unwrap_or_else(|| {
             terminal_size::terminal_size()
@@ -269,6 +270,14 @@ impl MietteHandlerOpts {
                  .0 as usize
         })
     }
+
+    #[cfg(miri)]
+    // miri doesn't support a syscall (specifically ioctl)
+    // performed by terminal_size, which causes test execution to fail
+    // so when miri is running we'll just fallback to a constant
+    pub(crate) fn get_width(&self) -> usize {
+        self.width.unwrap_or(80)
+    }
 }
 
 /**

tests/compiletest.rs

@@ -1,4 +1,5 @@
 #[rustversion::attr(not(nightly), ignore)]
+#[cfg_attr(miri, ignore)]
 #[test]
 fn ui() {
     let t = trybuild::TestCases::new();