1 files changed, 26 insertions, 19 deletions

diff --git a/clippy_dev/src/lib.rs b/clippy_dev/src/lib.rs
index 4531d9b39c0..bec415aae94 100644
--- a/clippy_dev/src/lib.rs
+++ b/clippy_dev/src/lib.rs
@@ -62,13 +62,25 @@ impl Lint {
     }
 
     /// Returns all non-deprecated lints and non-internal lints
-    pub fn usable_lints(lints: impl Iterator<Item = Self>) -> impl Iterator<Item = Self> {
-        lints.filter(|l| l.deprecation.is_none() && !l.group.starts_with("internal"))
+    #[must_use]
+    pub fn usable_lints(lints: &[Self]) -> Vec<Self> {
+        lints
+            .iter()
+            .filter(|l| l.deprecation.is_none() && !l.group.starts_with("internal"))
+            .cloned()
+            .collect()
     }
 
     /// Returns all internal lints (not `internal_warn` lints)
-    pub fn internal_lints(lints: impl Iterator<Item = Self>) -> impl Iterator<Item = Self> {
-        lints.filter(|l| l.group == "internal")
+    #[must_use]
+    pub fn internal_lints(lints: &[Self]) -> Vec<Self> {
+        lints.iter().filter(|l| l.group == "internal").cloned().collect()
+    }
+
+    /// Returns all deprecated lints
+    #[must_use]
+    pub fn deprecated_lints(lints: &[Self]) -> Vec<Self> {
+        lints.iter().filter(|l| l.deprecation.is_some()).cloned().collect()
     }
 
     /// Returns the lints in a `HashMap`, grouped by the different lint groups
@@ -80,9 +92,8 @@ impl Lint {
 
 /// Generates the Vec items for `register_lint_group` calls in `clippy_lints/src/lib.rs`.
 #[must_use]
-pub fn gen_lint_group_list(lints: &[Lint]) -> Vec<String> {
+pub fn gen_lint_group_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
-        .into_iter()
         .filter_map(|l| {
             if l.deprecation.is_some() {
                 None
@@ -96,9 +107,8 @@ pub fn gen_lint_group_list(lints: &[Lint]) -> Vec<String> {
 
 /// Generates the `pub mod module_name` list in `clippy_lints/src/lib.rs`.
 #[must_use]
-pub fn gen_modules_list(lints: &[Lint]) -> Vec<String> {
+pub fn gen_modules_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
-        .iter()
         .map(|l| &l.module)
         .unique()
         .map(|module| format!("pub mod {};", module))
@@ -108,9 +118,8 @@ pub fn gen_modules_list(lints: &[Lint]) -> Vec<String> {
 
 /// Generates the list of lint links at the bottom of the README
 #[must_use]
-pub fn gen_changelog_lint_list(lints: &[Lint]) -> Vec<String> {
+pub fn gen_changelog_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
-        .iter()
         .sorted_by_key(|l| l.name.clone())
         .filter_map(|l| {
             if l.group.starts_with("internal") {
@@ -124,9 +133,8 @@ pub fn gen_changelog_lint_list(lints: &[Lint]) -> Vec<String> {
 
 /// Generates the `register_removed` code in `./clippy_lints/src/lib.rs`.
 #[must_use]
-pub fn gen_deprecated(lints: &[Lint]) -> Vec<String> {
+pub fn gen_deprecated<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
-        .iter()
         .filter_map(|l| {
             l.clone().deprecation.map(|depr_text| {
                 vec![
@@ -142,11 +150,10 @@ pub fn gen_deprecated(lints: &[Lint]) -> Vec<String> {
 }
 
 #[must_use]
-pub fn gen_register_lint_list(lints: &[Lint]) -> Vec<String> {
+pub fn gen_register_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     let pre = "    store.register_lints(&[".to_string();
     let post = "    ]);".to_string();
     let mut inner = lints
-        .iter()
         .map(|l| format!("        &{}::{},", l.module, l.name.to_uppercase()))
         .sorted()
         .collect::<Vec<String>>();
@@ -421,7 +428,7 @@ fn test_usable_lints() {
         None,
         "module_name",
     )];
-    assert_eq!(expected, Lint::usable_lints(lints.into_iter()).collect::<Vec<Lint>>());
+    assert_eq!(expected, Lint::usable_lints(&lints));
 }
 
 #[test]
@@ -457,7 +464,7 @@ fn test_gen_changelog_lint_list() {
         format!("[`should_assert_eq`]: {}#should_assert_eq", DOCS_LINK.to_string()),
         format!("[`should_assert_eq2`]: {}#should_assert_eq2", DOCS_LINK.to_string()),
     ];
-    assert_eq!(expected, gen_changelog_lint_list(&lints));
+    assert_eq!(expected, gen_changelog_lint_list(lints.iter()));
 }
 
 #[test]
@@ -492,7 +499,7 @@ fn test_gen_deprecated() {
     .into_iter()
     .map(String::from)
     .collect();
-    assert_eq!(expected, gen_deprecated(&lints));
+    assert_eq!(expected, gen_deprecated(lints.iter()));
 }
 
 #[test]
@@ -507,7 +514,7 @@ fn test_gen_modules_list() {
         "pub mod another_module;".to_string(),
         "pub mod module_name;".to_string(),
     ];
-    assert_eq!(expected, gen_modules_list(&lints));
+    assert_eq!(expected, gen_modules_list(lints.iter()));
 }
 
 #[test]
@@ -523,5 +530,5 @@ fn test_gen_lint_group_list() {
         "        LintId::of(&module_name::INTERNAL),".to_string(),
         "        LintId::of(&module_name::SHOULD_ASSERT_EQ),".to_string(),
     ];
-    assert_eq!(expected, gen_lint_group_list(&lints));
+    assert_eq!(expected, gen_lint_group_list(lints.iter()));
 }