Test clippy_utils in CI

This makes sure that the tests in clippy_utils are run in CI.

When looking into this I discovered that two tests were failing and
multiple doc tests were failing. This fixes those tests and enables a
few more doc tests.

4 files changed, 25 insertions, 10 deletions

diff --git a/.github/workflows/clippy.yml b/.github/workflows/clippy.yml
index 0339de77f3c..3d8c39408a9 100644
--- a/.github/workflows/clippy.yml
+++ b/.github/workflows/clippy.yml
@@ -58,6 +58,10 @@ jobs:
       run: cargo test --features deny-warnings,internal-lints,metadata-collector-lint
       working-directory: clippy_lints
 
+    - name: Test clippy_utils
+      run: cargo test --features deny-warnings,internal-lints,metadata-collector-lint
+      working-directory: clippy_utils
+
     - name: Test rustc_tools_util
       run: cargo test --features deny-warnings
       working-directory: rustc_tools_util
diff --git a/.github/workflows/clippy_bors.yml b/.github/workflows/clippy_bors.yml
index 1f4d666c7a9..8b644aa2817 100644
--- a/.github/workflows/clippy_bors.yml
+++ b/.github/workflows/clippy_bors.yml
@@ -121,6 +121,10 @@ jobs:
       run: cargo test --features deny-warnings,internal-lints,metadata-collector-lint
       working-directory: clippy_lints
 
+    - name: Test clippy_utils
+      run: cargo test --features deny-warnings,internal-lints,metadata-collector-lint
+      working-directory: clippy_utils
+
     - name: Test rustc_tools_util
       run: cargo test --features deny-warnings
       working-directory: rustc_tools_util
diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs
index d384c5a069e..76f4408573b 100644
--- a/clippy_utils/src/lib.rs
+++ b/clippy_utils/src/lib.rs
@@ -156,18 +156,18 @@ pub fn differing_macro_contexts(lhs: Span, rhs: Span) -> bool {
 /// instead.
 ///
 /// Examples:
-/// ```ignore
+/// ```
 /// let abc = 1;
 /// //        ^ output
 /// let def = abc;
-/// dbg!(def)
+/// dbg!(def);
 /// //   ^^^ input
 ///
 /// // or...
 /// let abc = 1;
 /// let def = abc + 2;
 /// //        ^^^^^^^ output
-/// dbg!(def)
+/// dbg!(def);
 /// //   ^^^ input
 /// ```
 pub fn expr_or_init<'a, 'b, 'tcx: 'b>(cx: &LateContext<'tcx>, mut expr: &'a Expr<'b>) -> &'a Expr<'b> {
@@ -1136,7 +1136,7 @@ pub fn find_macro_calls(names: &[&str], body: &Body<'_>) -> Vec<Span> {
 
 /// Extends the span to the beginning of the spans line, incl. whitespaces.
 ///
-/// ```rust,ignore
+/// ```rust
 ///        let x = ();
 /// //             ^^
 /// // will be converted to
@@ -1337,7 +1337,7 @@ pub fn is_adjusted(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
     cx.typeck_results().adjustments().get(e.hir_id).is_some()
 }
 
-/// Returns the pre-expansion span if is this comes from an expansion of the
+/// Returns the pre-expansion span if this comes from an expansion of the
 /// macro `name`.
 /// See also [`is_direct_expn_of`].
 #[must_use]
@@ -1364,7 +1364,8 @@ pub fn is_expn_of(mut span: Span, name: &str) -> Option<Span> {
 /// of the macro `name`.
 /// The difference with [`is_expn_of`] is that in
 /// ```rust
-/// # macro_rules! foo { ($e:tt) => { $e } }; macro_rules! bar { ($e:expr) => { $e } }
+/// # macro_rules! foo { ($name:tt!$args:tt) => { $name!$args } }
+/// # macro_rules! bar { ($e:expr) => { $e } }
 /// foo!(bar!(42));
 /// ```
 /// `42` is considered expanded from `foo!` and `bar!` by `is_expn_of` but only
@@ -1905,7 +1906,9 @@ pub fn is_no_core_crate(cx: &LateContext<'_>) -> bool {
 
 /// Check if parent of a hir node is a trait implementation block.
 /// For example, `f` in
-/// ```rust,ignore
+/// ```rust
+/// # struct S;
+/// # trait Trait { fn f(); }
 /// impl Trait for S {
 ///     fn f() {}
 /// }
diff --git a/clippy_utils/src/str_utils.rs b/clippy_utils/src/str_utils.rs
index cba96e05a24..6dc52bf2325 100644
--- a/clippy_utils/src/str_utils.rs
+++ b/clippy_utils/src/str_utils.rs
@@ -15,6 +15,7 @@ impl StrIndex {
 /// Returns the index of the character after the first camel-case component of `s`.
 ///
 /// ```
+/// # use clippy_utils::str_utils::{camel_case_until, StrIndex};
 /// assert_eq!(camel_case_until("AbcDef"), StrIndex::new(6, 6));
 /// assert_eq!(camel_case_until("ABCD"), StrIndex::new(0, 0));
 /// assert_eq!(camel_case_until("AbcDD"), StrIndex::new(3, 3));
@@ -55,9 +56,10 @@ pub fn camel_case_until(s: &str) -> StrIndex {
     }
 }
 
-/// Returns index of the last camel-case component of `s`.
+/// Returns index of the first camel-case component of `s`.
 ///
 /// ```
+/// # use clippy_utils::str_utils::{camel_case_start, StrIndex};
 /// assert_eq!(camel_case_start("AbcDef"), StrIndex::new(0, 0));
 /// assert_eq!(camel_case_start("abcDef"), StrIndex::new(3, 3));
 /// assert_eq!(camel_case_start("ABCD"), StrIndex::new(4, 4));
@@ -69,9 +71,9 @@ pub fn camel_case_start(s: &str) -> StrIndex {
     let char_count = s.chars().count();
     let range = 0..char_count;
     let mut iter = range.rev().zip(s.char_indices().rev());
-    if let Some((char_index, (_, first))) = iter.next() {
+    if let Some((_, (_, first))) = iter.next() {
         if !first.is_lowercase() {
-            return StrIndex::new(char_index, s.len());
+            return StrIndex::new(char_count, s.len());
         }
     } else {
         return StrIndex::new(char_count, s.len());
@@ -116,6 +118,7 @@ impl StrCount {
 /// Returns the number of chars that match from the start
 ///
 /// ```
+/// # use clippy_utils::str_utils::{count_match_start, StrCount};
 /// assert_eq!(count_match_start("hello_mouse", "hello_penguin"), StrCount::new(6, 6));
 /// assert_eq!(count_match_start("hello_clippy", "bye_bugs"), StrCount::new(0, 0));
 /// assert_eq!(count_match_start("hello_world", "hello_world"), StrCount::new(11, 11));
@@ -141,6 +144,7 @@ pub fn count_match_start(str1: &str, str2: &str) -> StrCount {
 /// Returns the number of chars and bytes that match from the end
 ///
 /// ```
+/// # use clippy_utils::str_utils::{count_match_end, StrCount};
 /// assert_eq!(count_match_end("hello_cat", "bye_cat"), StrCount::new(4, 4));
 /// assert_eq!(count_match_end("if_item_thing", "enum_value"), StrCount::new(0, 0));
 /// assert_eq!(count_match_end("Clippy", "Clippy"), StrCount::new(6, 6));