Fix mutation baseline by making heuristics::text doctests compile

Makefile

@@ -18,6 +18,9 @@ clean: ## Remove build artifacts
 
 test: ## Run tests with warnings treated as errors
 	RUSTFLAGS="-D warnings" $(CARGO) test --all-targets --all-features $(BUILD_JOBS)
+	# --all-targets skips doctests, so run them explicitly to keep CI
+	# aligned with the plain `cargo test` used by cargo-mutants.
+	RUSTFLAGS="-D warnings" $(CARGO) test --doc --all-features $(BUILD_JOBS)
 
 test-workflow-contracts: ## Validate the mutation-testing caller contract
 	uv run --with 'pytest>=8' --with 'pyyaml>=6' pytest tests/workflow_contracts -q

src/heuristics/mod.rs

@@ -3,7 +3,7 @@
 pub mod ambiguity;
 pub mod complexity;
 pub mod depth;
-pub(crate) mod text;
+pub mod text;
 
 pub use ambiguity::{AmbiguityHeuristic, AmbiguityHeuristicError};
 pub use complexity::{HeuristicComplexity, HeuristicComplexityError};

src/heuristics/text.rs

@@ -40,6 +40,7 @@ pub fn normalize_tokens(input: &str) -> Vec<String> {
 /// let count = weighted_count(tokens.iter().map(String::as_str), &["and"], 2);
 /// assert_eq!(count, 2);
 /// ```
+#[must_use]
 pub fn weighted_count<T: AsRef<str>>(
     tokens: impl Iterator<Item = T>,
     patterns: &[&str],