Remove dependency on rustfmt installation for consumers (#221)

CHANGELOG.adoc

@@ -13,6 +13,25 @@
 
 == Unreleased changes (release date TBD)
 
+Breaking change: this release removes the `ToString` implementation for
+`TypeSpace` and the `rustfmt-wrapper` dependency. This allows users to use a
+pretty printing method of choice. Users can use the `ToTokens` implementation of
+`TypeSpace`:
+
+Before:
+[source,rust]
+----
+let typespace = TypeSpace::default();
+typespace.to_string()
+----
+
+After:
+[source,rust]
+----
+let typespace = TypeSpace::default();
+typespace.to_stream().to_string()
+----
+
 https://github.com/oxidecomputer/typify/compare/v0.0.10\...HEAD[Full list of commits]
 
 * Allow per-type renames and derive macro applications (#131)

README.md

@@ -3,17 +3,18 @@
 Typify compiles JSON Schema documents into Rust types. It can be used in one of
 three ways:
 
-- via the macro `import_types!("types.json")` to generate Rust types directly
-in your program
+- via the macro `import_types!("types.json")` to generate Rust types directly in
+  your program
 
 - via a builder interface to generate Rust types in `build.rs`
 
 - or via the builder functions to generate persistent files e.g. when building
-API bindings.
+  API bindings.
 
 ## JSON Schema → Rust types
 
-Typify translates JSON Schema types in a few different ways depending on some basic properties of the schema:
+Typify translates JSON Schema types in a few different ways depending on some
+basic properties of the schema:
 
 ### Built-in types
 
@@ -23,17 +24,17 @@ appropriate built-in type based on type attributes. For example, a JSON Schema
 might specify a maximum and/or minimum that indicates the appropriate integral
 type to use.
 
-String schemas that include a `format` are represented with the appropriate
-Rust type. For example `{ "type": "string", "format": "uuid" }` is represented
-as a `uuid::Uuid` (which requires the `uuid` crate be included as a dependency).
+String schemas that include a `format` are represented with the appropriate Rust
+type. For example `{ "type": "string", "format": "uuid" }` is represented as a
+`uuid::Uuid` (which requires the `uuid` crate be included as a dependency).
 
 ### Arrays
 
-JSON Schema arrays can turn into one of three Rust types `Vec<T>`,
-`HashSet<T>`, and tuples depending on the schema properties. An array may have
-a fixed length that matches a fixed list of item types; this is well
-represented by a Rust tuples. The distinction between `Vec<T>` and `HashSet<T>`
-is only if the schema's `uniqueItems` field is `false` or `true` respectively.
+JSON Schema arrays can turn into one of three Rust types `Vec<T>`, `HashSet<T>`,
+and tuples depending on the schema properties. An array may have a fixed length
+that matches a fixed list of item types; this is well represented by a Rust
+tuples. The distinction between `Vec<T>` and `HashSet<T>` is only if the
+schema's `uniqueItems` field is `false` or `true` respectively.
 
 ### Objects
 
@@ -49,14 +50,43 @@ simply get the `#[serde(default)]` attribute (so you won't see e.g.
 
 ### OneOf
 
-The `OneOf` construct maps to a Rust enum. Typify maps this to the various [serde enum types](https://serde.rs/enum-representations.html).
+The `OneOf` construct maps to a Rust enum. Typify maps this to the various
+[serde enum types](https://serde.rs/enum-representations.html).
 
 ### AnyOf / AllOf
 
 The `anyOf` and `allOf` constructs are a little trickier to handle, but (in
 general) Typify models these as structs where each member is decorated with the
 `#[serde(flatten)]` attribute (with `Option` wrappers in the case of `anyOf`).
 
+## Formatting
+
+By default Typify's generated code is not formatted. If formatted code is
+preferred, crates like [rustfmt-wrapper](https://docs.rs/rustfmt-wrapper) and
+[prettyplease](https://docs.rs/prettyplease) can be used to format the generated
+code before writing it to a file.
+
+The examples below show different ways to convert a `TypeSpace` to a string
+(`typespace` is a `typify::TypeSpace`).
+
+### No formatting
+
+```rust
+typespace.to_stream().to_string()
+```
+
+### Rustfmt
+
+```rust
+rustfmt_wrapper::rustfmt(typespace.to_stream().to_string())?
+```
+
+### Prettyplease
+
+```rust
+prettyplease::unparse(&syn::parse2::<syn::File>(typespace.to_stream())?)
+```
+
 ## WIP
 
 Typify is a work in progress. Changes that affect output will be indicated with
@@ -73,9 +103,9 @@ Bounded numbers aren't very well handled. Consider, for example, the schema:
 
 ```json
 {
-    "type": "integer",
-    "minimum": 1,
-    "maximum": 6
+  "type": "integer",
+  "minimum": 1,
+  "maximum": 6
 }
 ```
 
@@ -98,4 +128,5 @@ struct A {
     a: Box<A>,
 }
 ```
+
 .. but it does not support more complex cycles such as A -> B -> A.

cargo-typify/src/lib.rs

@@ -99,7 +99,7 @@ pub fn convert(args: &CliArgs) -> Result<String> {
 use serde::{Deserialize, Serialize};
 ";
 
-    let contents = format!("{intro}\n{}", type_space.to_string());
+    let contents = format!("{intro}\n{}", type_space.to_stream().to_string());
 
     let contents = rustfmt_wrapper::rustfmt(contents).wrap_err("Failed to format Rust code")?;
 

example-build/Cargo.toml

@@ -9,6 +9,8 @@ serde = "1.0"
 serde_json = "1.0.94"
 
 [build-dependencies]
+prettyplease = "0.1"
 schemars = "0.8"
 serde_json = "1.0.94"
+syn = "1.0.109"
 typify = { path = "../typify" }

example-build/build.rs

@@ -18,7 +18,7 @@ fn main() {
     let contents = format!(
         "{}\n{}",
         "use serde::{Deserialize, Serialize};",
-        type_space.to_string()
+        prettyplease::unparse(&syn::parse2::<syn::File>(type_space.to_stream()).unwrap())
     );
 
     let mut out_file = Path::new(&env::var("OUT_DIR").unwrap()).to_path_buf();

typify-impl/Cargo.toml

@@ -14,7 +14,6 @@ log = "0.4"
 proc-macro2 = "1.0"
 quote = "1.0"
 regress = "0.5.0"
-rustfmt-wrapper = "0.2"
 schemars = "0.8.12"
 serde_json = "1.0"
 syn = { version = "1.0", features = ["full"] }
@@ -24,6 +23,7 @@ unicode-ident = "1.0.8"
 [dev-dependencies]
 expectorate = "1.0"
 paste = "1.0"
+rustfmt-wrapper = "0.2"
 schema = "0.0.1"
 schemars = { version = "0.8.12", features = ["uuid1"] }
 serde = "1.0"

typify-impl/src/lib.rs

@@ -7,7 +7,6 @@ use log::info;
 use output::OutputSpace;
 use proc_macro2::TokenStream;
 use quote::{quote, ToTokens};
-use rustfmt_wrapper::rustfmt;
 use schemars::schema::{Metadata, Schema};
 use thiserror::Error;
 use type_entry::{
@@ -801,12 +800,6 @@ impl TypeSpace {
     }
 }
 
-impl ToString for TypeSpace {
-    fn to_string(&self) -> String {
-        rustfmt(self.to_stream().to_string()).unwrap()
-    }
-}
-
 impl ToTokens for TypeSpace {
     fn to_tokens(&self, tokens: &mut TokenStream) {
         tokens.extend(self.to_stream())

typify-test/Cargo.toml

@@ -11,6 +11,8 @@ serde_json = "1.0.94"
 
 [build-dependencies]
 ipnetwork = { version = "0.20.0", features = ["schemars"] }
+prettyplease = "0.1"
 schemars = "0.8.12"
 serde = "1.0.155"
+syn = "1.0.109"
 typify = { path = "../typify" }

typify-test/build.rs

@@ -109,7 +109,7 @@ fn main() {
     let contents = format!(
         "{}\n{}",
         "use serde::{Deserialize, Serialize};",
-        type_space.to_string()
+        prettyplease::unparse(&syn::parse2::<syn::File>(type_space.to_stream()).unwrap())
     );
 
     let mut out_file = Path::new(&env::var("OUT_DIR").unwrap()).to_path_buf();