Add mdbook-core

This is intended as a shared, internal library that will be used by
other mdbook crates. The intention is that those crates will either
directly use, or reexport items from this crate.

Initially this includes MDBOOK_VERSION, which will get reexported from
the preprocessor and renderer crates.

Author: ehuss

Cargo.lock

@@ -1,5 +1,9 @@
 [workspace]
-members = [".", "examples/remove-emphasis/mdbook-remove-emphasis"]
+members = [
+    ".",
+    "crates/*",
+    "examples/remove-emphasis/mdbook-remove-emphasis",
+]
 
 [workspace.lints.clippy]
 all = { level = "allow", priority = -2 }
@@ -16,6 +20,9 @@ license = "MPL-2.0"
 repository = "https://github.com/rust-lang/mdBook"
 rust-version = "1.85.0" # Keep in sync with installation.md and .github/workflows/main.yml
 
+[workspace.dependencies]
+mdbook-core = { path = "crates/mdbook-core" }
+
 [package]
 name = "mdbook"
 version = "0.4.52"
@@ -43,6 +50,7 @@ env_logger = "0.11.1"
 handlebars = "6.0"
 hex = "0.4.3"
 log = "0.4.17"
+mdbook-core.workspace = true
 memchr = "2.5.0"
 opener = "0.8.1"
 pulldown-cmark = { version = "0.10.0", default-features = false, features = ["html"] } # Do not update, part of the public api.

Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "mdbook-core"
+version = "0.5.0-alpha.1"
+description = "The base support library for mdbook, intended for internal use only"
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+
+[lints]
+workspace = true

crates/mdbook-core/Cargo.toml

@@ -0,0 +1,7 @@
+//! The base support library for mdbook, intended for internal use only.
+
+/// The current version of `mdbook`.
+///
+/// This is provided as a way for custom preprocessors and renderers to do
+/// compatibility checks.
+pub const MDBOOK_VERSION: &str = env!("CARGO_PKG_VERSION");

crates/mdbook-core/src/lib.rs

@@ -88,16 +88,11 @@ pub mod renderer;
 pub mod theme;
 pub mod utils;
 
-/// The current version of `mdbook`.
-///
-/// This is provided as a way for custom preprocessors and renderers to do
-/// compatibility checks.
-pub const MDBOOK_VERSION: &str = env!("CARGO_PKG_VERSION");
-
 pub use crate::book::BookItem;
 pub use crate::book::MDBook;
 pub use crate::config::Config;
 pub use crate::renderer::Renderer;
+pub use mdbook_core::MDBOOK_VERSION;
 
 /// The error types used through out this crate.
 pub mod errors {