3 files changed, 34 insertions, 0 deletions
diff --git a/src/tools/rustbook/Cargo.lock b/src/tools/rustbook/Cargo.lock
index 75b89a162e9..df051ed447e 100644
--- a/src/tools/rustbook/Cargo.lock
+++ b/src/tools/rustbook/Cargo.lock
@@ -662,6 +662,20 @@ dependencies = [
 ]
 
 [[package]]
+name = "mdbook-spec"
+version = "0.1.2"
+dependencies = [
+ "anyhow",
+ "mdbook",
+ "once_cell",
+ "pathdiff",
+ "regex",
+ "semver",
+ "serde_json",
+ "tempfile",
+]
+
+[[package]]
 name = "mdbook-trpl-listing"
 version = "0.1.0"
 dependencies = [
@@ -795,6 +809,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "pathdiff"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8835116a5c179084a830efb3adc117ab007512b535bc1a21c991d3b32a6b44dd"
+
+[[package]]
 name = "percent-encoding"
 version = "2.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1079,6 +1099,7 @@ dependencies = [
  "env_logger",
  "mdbook",
  "mdbook-i18n-helpers",
+ "mdbook-spec",
  "mdbook-trpl-listing",
  "mdbook-trpl-note",
 ]
diff --git a/src/tools/rustbook/Cargo.toml b/src/tools/rustbook/Cargo.toml
index 51ba58483c5..2c29a2848b7 100644
--- a/src/tools/rustbook/Cargo.toml
+++ b/src/tools/rustbook/Cargo.toml
@@ -12,6 +12,7 @@ env_logger = "0.11"
 mdbook-trpl-listing = { path = "../../doc/book/packages/mdbook-trpl-listing" }
 mdbook-trpl-note = { path = "../../doc/book/packages/mdbook-trpl-note" }
 mdbook-i18n-helpers = "0.3.3"
+mdbook-spec = { path = "../../doc/reference/mdbook-spec"}
 
 [dependencies.mdbook]
 version = "0.4.37"
diff --git a/src/tools/rustbook/src/main.rs b/src/tools/rustbook/src/main.rs
index 31bba56adde..e94c2f5958e 100644
--- a/src/tools/rustbook/src/main.rs
+++ b/src/tools/rustbook/src/main.rs
@@ -9,6 +9,7 @@ use mdbook::errors::Result as Result3;
 use mdbook::MDBook;
 use mdbook_i18n_helpers::preprocessors::Gettext;
 
+use mdbook_spec::Spec;
 use mdbook_trpl_listing::TrplListing;
 use mdbook_trpl_note::TrplNote;
 
@@ -83,6 +84,13 @@ pub fn build(args: &ArgMatches) -> Result3<()> {
         book.config.build.build_dir = dest_dir.into();
     }
 
+    // NOTE: Replacing preprocessors using this technique causes error
+    // messages to be displayed when the original preprocessor doesn't work
+    // (but it otherwise succeeds).
+    //
+    // This should probably be fixed in mdbook to remove the existing
+    // preprocessor, or this should modify the config and use
+    // MDBook::load_with_config.
     if book.config.get_preprocessor("trpl-note").is_some() {
         book.with_preprocessor(TrplNote);
     }
@@ -91,6 +99,10 @@ pub fn build(args: &ArgMatches) -> Result3<()> {
         book.with_preprocessor(TrplListing);
     }
 
+    if book.config.get_preprocessor("spec").is_some() {
+        book.with_preprocessor(Spec::new());
+    }
+
     book.build()?;
 
     Ok(())