replace rustlings-macros with build script

This turns rustlings into a single crate, which is less complicated to
publish releases for. A follow-up step might be to remove the workspace
configuration.

The motivation was this discussion on Zulip:
https://rust-lang.zulipchat.com/#narrow/channel/334454-t-lang-docs.2Frustlings/topic/Trusted.20publishing/near/638396712

CONTRIBUTING.md

@@ -52,7 +52,7 @@ When updating an exercise, check if its solution needs to be updated.
 - Make sure to put in some helpful links, and link to sections of The Book in `exercises/yourTopic/README.md`.
 - In the exercise, add a `// TODO: …` comment where user changes are required.
 - Add a solution at `solutions/yourTopic/yourTopicN.rs` with comments explaining it.
-- Add the [metadata for your exercise](#exercise-metadata) in the `rustlings-macros/info.toml` file.
+- Add the [metadata for your exercise](#exercise-metadata) in the `info.toml` file.
 - [Open a pull request](#pull-requests).
 
 ### Exercise Metadata

Cargo.lock

@@ -434,8 +434,8 @@ dependencies = [
  "clap",
  "crossterm",
  "notify",
+ "quote",
  "rustix",
- "rustlings-macros",
  "serde",
  "serde_json",
  "shlex",
@@ -444,15 +444,6 @@ dependencies = [
  "wait-timeout",
 ]
 
-[[package]]
-name = "rustlings-macros"
-version = "6.5.0"
-dependencies = [
- "quote",
- "serde",
- "toml",
-]
-
 [[package]]
 name = "same-file"
 version = "1.0.6"

Cargo.toml

@@ -36,10 +36,12 @@ keywords = [
 ]
 include = [
   "/src/",
+  "/build.rs",
   "/exercises/",
   "/solutions/",
   # A symlink to be able to include `dev/Cargo.toml` although `dev` is excluded.
   "/dev-Cargo.toml",
+  "/info.toml",
   "/README.md",
   "/LICENSE",
 ]
@@ -49,7 +51,6 @@ anyhow = "1"
 clap = { version = "4", features = ["derive"] }
 crossterm = { version = "0.29", default-features = false, features = ["windows", "events"] }
 notify = "8"
-rustlings-macros = { path = "rustlings-macros", version = "=6.5.0" }
 serde_json = "1"
 serde.workspace = true
 shlex = "2"
@@ -59,6 +60,11 @@ wait-timeout = "0.2"
 [target.'cfg(not(windows))'.dependencies]
 rustix = { version = "1.0", default-features = false, features = ["std", "stdio", "termios"] }
 
+[build-dependencies]
+quote = "1"
+serde.workspace = true
+toml.workspace = true
+
 [dev-dependencies]
 tempfile = "3"
 

build.rs

@@ -1,5 +1,98 @@
+use quote::quote;
+use serde::Deserialize;
+
 fn main() {
     // Fix building from source on Windows because it can't handle file links.
     #[cfg(windows)]
     let _ = std::fs::copy("dev/Cargo.toml", "dev-Cargo.toml");
+
+    process_info_toml();
+}
+
+#[derive(Deserialize)]
+struct ExerciseInfo<'a> {
+    name: &'a str,
+    dir: &'a str,
+    #[serde(default)]
+    input_files: Vec<&'a str>,
+}
+
+#[derive(Deserialize)]
+struct InfoFile<'a> {
+    #[serde(borrow)]
+    exercises: Vec<ExerciseInfo<'a>>,
+}
+
+/// Translates the data in info.toml to Rust data structures to be embedded in
+/// the final binary.
+pub fn process_info_toml() {
+    let info_file = include_str!("info.toml");
+    let info = toml::de::from_str::<InfoFile>(info_file).expect("Failed to parse `info.toml`");
+    let exercises = info.exercises;
+    let manifest_dir = env!("CARGO_MANIFEST_DIR");
+
+    let exercise_files = exercises.iter().map(|exercise| {
+        format!(
+            "{manifest_dir}/exercises/{}/{}.rs",
+            exercise.dir, exercise.name
+        )
+    });
+    let solution_files = exercises.iter().map(|exercise| {
+        format!(
+            "{manifest_dir}/solutions/{}/{}.rs",
+            exercise.dir, exercise.name
+        )
+    });
+
+    let mut dirs = Vec::with_capacity(32);
+    let mut dir_inds = vec![0; exercises.len()];
+
+    for (exercise, dir_ind) in exercises.iter().zip(&mut dir_inds) {
+        // The directory is often the last one inserted.
+        if let Some(ind) = dirs.iter().rev().position(|dir| *dir == exercise.dir) {
+            *dir_ind = dirs.len() - 1 - ind;
+            continue;
+        }
+
+        dirs.push(exercise.dir);
+        *dir_ind = dirs.len() - 1;
+    }
+
+    let input_files = exercises.iter().map(|exercise| {
+        let names = exercise.input_files.iter();
+        let paths = exercise
+            .input_files
+            .iter()
+            .map(|f| format!("{manifest_dir}/exercises/{}/{}", exercise.dir, f));
+        quote! {
+            &[#(InputFile {
+                name: #names,
+                content: include_str!(#paths),
+            }),*]
+        }
+    });
+
+    let readmes = dirs
+        .iter()
+        .map(|dir| format!("{manifest_dir}/exercises/{dir}/README.md"));
+
+    let embedded_files = quote! {
+        EmbeddedFiles {
+            info_file: #info_file,
+            exercise_files: &[#(ExerciseFiles {
+                exercise: include_bytes!(#exercise_files),
+                solution: include_bytes!(#solution_files),
+                dir_ind: #dir_inds,
+                input_files: #input_files,
+            }),*],
+            exercise_dirs: &[#(ExerciseDir { name: #dirs, readme: include_bytes!(#readmes) }),*],
+        }
+    };
+
+    let out_dir = std::env::var("OUT_DIR").unwrap();
+    std::fs::write(
+        format!("{out_dir}/embedded_files.rs"),
+        embedded_files.to_string(),
+    )
+    .unwrap();
 }

rustlings-macros/Cargo.toml

@@ -1,24 +0,0 @@
-[package]
-name = "rustlings-macros"
-description = "A macros crate intended to be used only by Rustlings"
-version.workspace = true
-authors.workspace = true
-repository.workspace = true
-license.workspace = true
-edition.workspace = true
-rust-version.workspace = true
-include = [
-  "/src/",
-  "/info.toml",
-]
-
-[lib]
-proc-macro = true
-
-[dependencies]
-quote = "1"
-serde.workspace = true
-toml.workspace = true
-
-[lints]
-workspace = true

rustlings-macros/src/lib.rs

@@ -1,77 +0,0 @@
-use proc_macro::TokenStream;
-use quote::quote;
-use serde::Deserialize;
-
-#[derive(Deserialize)]
-struct ExerciseInfo<'a> {
-    name: &'a str,
-    dir: &'a str,
-    #[serde(default)]
-    input_files: Vec<&'a str>,
-}
-
-#[derive(Deserialize)]
-struct InfoFile<'a> {
-    #[serde(borrow)]
-    exercises: Vec<ExerciseInfo<'a>>,
-}
-
-#[proc_macro]
-pub fn include_files(_: TokenStream) -> TokenStream {
-    let info_file = include_str!("../info.toml");
-    let info = toml::de::from_str::<InfoFile>(info_file).expect("Failed to parse `info.toml`");
-    let exercises = info.exercises;
-
-    let exercise_files = exercises
-        .iter()
-        .map(|exercise| format!("../exercises/{}/{}.rs", exercise.dir, exercise.name));
-    let solution_files = exercises
-        .iter()
-        .map(|exercise| format!("../solutions/{}/{}.rs", exercise.dir, exercise.name));
-
-    let mut dirs = Vec::with_capacity(32);
-    let mut dir_inds = vec![0; exercises.len()];
-
-    for (exercise, dir_ind) in exercises.iter().zip(&mut dir_inds) {
-        // The directory is often the last one inserted.
-        if let Some(ind) = dirs.iter().rev().position(|dir| *dir == exercise.dir) {
-            *dir_ind = dirs.len() - 1 - ind;
-            continue;
-        }
-
-        dirs.push(exercise.dir);
-        *dir_ind = dirs.len() - 1;
-    }
-
-    let input_files = exercises.iter().map(|exercise| {
-        let names = exercise.input_files.iter();
-        let paths = exercise
-            .input_files
-            .iter()
-            .map(|f| format!("../exercises/{}/{}", exercise.dir, f));
-        quote! {
-            &[#(InputFile {
-                name: #names,
-                content: include_str!(#paths),
-            }),*]
-        }
-    });
-
-    let readmes = dirs
-        .iter()
-        .map(|dir| format!("../exercises/{dir}/README.md"));
-
-    quote! {
-        EmbeddedFiles {
-            info_file: #info_file,
-            exercise_files: &[#(ExerciseFiles {
-                exercise: include_bytes!(#exercise_files),
-                solution: include_bytes!(#solution_files),
-                dir_ind: #dir_inds,
-                input_files: #input_files,
-            }),*],
-            exercise_dirs: &[#(ExerciseDir { name: #dirs, readme: include_bytes!(#readmes) }),*],
-        }
-    }
-    .into()
-}

src/embedded.rs

@@ -7,7 +7,7 @@ use std::{
 use crate::info_file::ExerciseInfo;
 
 /// Contains all embedded files.
-pub static EMBEDDED_FILES: EmbeddedFiles = rustlings_macros::include_files!();
+pub static EMBEDDED_FILES: EmbeddedFiles = include!(concat!(env!("OUT_DIR"), "/embedded_files.rs"));
 
 // Files related to one exercise.
 pub struct ExerciseFiles {