Initialize a test suite for wit-encoder (#1626)

* change `wit-encoder` indent to 2

* test empty `Result`s in `wit-encoder`

* import wit test files for `wit-encoder`

* use external wit test file for `functions.rs` test

* add `empty` test

* add `wit-encoder` overlap tests

* fix more existing tests

* Add `include` capabilities to `wit-encoder`

* tidy up

* rebase on main

* check in `.gitattributes` to normalize line endings

Rebasing brok

* remove additional wit files

* inline tests

Author: yoshuawuyts

.gitattributes

@@ -1,2 +1,3 @@
+* text=auto
 *.waves text eol=lf
 *.out text eol=lf

Cargo.lock

@@ -84,6 +84,7 @@ bitflags = "2.5.0"
 hashbrown = { version = "0.14.3", default-features = false, features = ['ahash'] }
 ahash = { version = "0.8.11", default-features = false }
 termcolor = "1.2.0"
+indoc = "2.0.5"
 
 wasm-compose = { version = "0.211.1", path = "crates/wasm-compose" }
 wasm-encoder = { version = "0.211.1", path = "crates/wasm-encoder" }

Cargo.toml

@@ -13,3 +13,6 @@ workspace = true
 [dependencies]
 semver = { workspace = true }
 pretty_assertions = { workspace = true }
+
+[dev-dependencies]
+indoc = { workspace = true }

crates/wit-encoder/Cargo.toml

@@ -108,7 +108,7 @@ where
 impl Results {
     // For the common case of an empty results list.
     pub fn empty() -> Results {
-        Results::Named(Default::default())
+        Results::Named(Params::empty())
     }
 
     pub fn anon(type_: Type) -> Results {
@@ -166,3 +166,14 @@ impl StandaloneFunc {
         self.docs = docs.map(|d| d.into());
     }
 }
+
+#[cfg(test)]
+mod test {
+    use crate::Results;
+
+    #[test]
+    fn is_empty() {
+        let res = Results::empty();
+        assert!(res.is_empty());
+    }
+}

crates/wit-encoder/src/function.rs

@@ -0,0 +1,26 @@
+use std::fmt;
+
+use crate::{Ident, Render};
+
+/// Enable the union of a world with another world
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct Include {
+    use_path: Ident,
+    include_names_list: Vec<String>,
+}
+
+impl Include {
+    pub fn new(use_path: impl Into<Ident>) -> Self {
+        Self {
+            use_path: use_path.into(),
+            include_names_list: vec![],
+        }
+    }
+}
+
+impl Render for Include {
+    fn render(&self, f: &mut fmt::Formatter<'_>, opts: &crate::RenderOpts) -> fmt::Result {
+        write!(f, "{}include {};\n", opts.spaces(), self.use_path)?;
+        Ok(())
+    }
+}

crates/wit-encoder/src/include.rs

@@ -8,6 +8,7 @@ mod enum_;
 mod flags;
 mod function;
 mod ident;
+mod include;
 mod interface;
 mod package;
 mod record;
@@ -24,6 +25,7 @@ pub use enum_::*;
 pub use flags::*;
 pub use function::*;
 pub use ident::*;
+pub use include::*;
 pub use interface::*;
 pub use package::*;
 pub use record::*;

crates/wit-encoder/src/lib.rs

@@ -41,16 +41,21 @@ impl Package {
 impl Render for Package {
     fn render(&self, f: &mut fmt::Formatter<'_>, opts: &RenderOpts) -> fmt::Result {
         write!(f, "{}package {};\n", opts.spaces(), self.name)?;
-        write!(f, "\n")?;
         for item in &self.items {
+            write!(f, "\n")?;
             match item {
                 PackageItem::Interface(interface) => {
                     if let Some(docs) = &interface.docs {
                         docs.render(f, opts)?;
                     }
-                    write!(f, "{}interface {} {{\n", opts.spaces(), interface.name)?;
-                    interface.items.render(f, &opts.indent())?;
-                    write!(f, "{}}}\n", opts.spaces())?;
+                    write!(f, "{}interface {} {{", opts.spaces(), interface.name)?;
+                    if !interface.items.is_empty() {
+                        write!(f, "\n")?;
+                        interface.items.render(f, &opts.indent())?;
+                        write!(f, "{}}}\n", opts.spaces())?;
+                    } else {
+                        write!(f, "}}\n")?;
+                    }
                 }
                 PackageItem::World(world) => {
                     world.render(f, opts)?;

crates/wit-encoder/src/package.rs

@@ -11,7 +11,7 @@ pub struct RenderOpts {
 impl Default for RenderOpts {
     fn default() -> Self {
         Self {
-            indent_width: 4,
+            indent_width: 2,
             ident_count: 0,
         }
     }

crates/wit-encoder/src/render.rs

@@ -317,8 +317,11 @@ impl Render for TypeDef {
                 if let Some(docs) = &self.docs {
                     docs.render(f, opts)?;
                 }
-                write!(f, "{}record {} {{\n", opts.spaces(), self.name)?;
-                for field in &record.fields {
+                write!(f, "{}record {} {{", opts.spaces(), self.name)?;
+                for (index, field) in record.fields.iter().enumerate() {
+                    if index == 0 {
+                        write!(f, "\n")?;
+                    }
                     let opts = opts.indent();
                     if let Some(docs) = &field.docs {
                         docs.render(f, &opts)?;