more

src/lib.rs

@@ -1,3 +1,5 @@
+#![feature(non_exhaustive_omitted_patterns_lint)]
+
 #[macro_use]
 extern crate tracing;
 
@@ -32,7 +34,7 @@ pub enum Cargo {
     Minimize(Options),
 }
 
-#[derive(clap::Args, Debug)]
+#[derive(clap::Args, Debug, Clone)]
 pub struct Options {
     /// Additional arguments to pass to cargo/rustc, separated by whitespace.
     #[arg(long)]
@@ -99,6 +101,9 @@ pub struct Options {
     /// Do not touch the following files.
     #[arg(long)]
     pub ignore_file: Vec<PathBuf>,
+
+    #[arg(skip)]
+    pub no_delete_functions: bool,
 }
 
 #[derive(Debug, Clone)]
@@ -177,6 +182,7 @@ impl Default for Options {
             script_path: None,
             script_path_lints: None,
             ignore_file: Vec::new(),
+            no_delete_functions: false,
         }
     }
 }

src/passes/item_deleter.rs

@@ -1,7 +1,7 @@
 use quote::ToTokens;
 use syn::{
-    visit_mut::VisitMut, Item, ItemConst, ItemEnum, ItemMacro, ItemMacro2, ItemMod, ItemStatic,
-    ItemStruct, ItemTrait, ItemType, ItemUnion,
+    visit_mut::VisitMut, Item, ItemConst, ItemEnum, ItemExternCrate, ItemFn, ItemMacro, ItemMacro2,
+    ItemMod, ItemStatic, ItemStruct, ItemTrait, ItemTraitAlias, ItemType, ItemUnion, Signature,
 };
 
 use crate::processor::{tracking, Pass, PassController, ProcessState, SourceFile};
@@ -31,8 +31,6 @@ impl<'a> Visitor<'a> {
 
     fn consider_deleting_item(&mut self, item: &Item) -> bool {
         match item {
-            // N.B. Do not delete ItemFn because that makes testing way harder
-            // and also the dead_lint should cover it all.
             Item::Impl(impl_) => {
                 self.current_path
                     .push(impl_.self_ty.clone().into_token_stream().to_string());
@@ -42,18 +40,25 @@ impl<'a> Visitor<'a> {
                 self.current_path.pop();
                 should_retain
             }
-            Item::Struct(ItemStruct { ident, .. })
+            Item::Fn(_) if self.checker.options.no_delete_functions => true,
+            Item::Fn(ItemFn {
+                sig: Signature { ident, .. },
+                ..
+            })
+            | Item::Struct(ItemStruct { ident, .. })
             | Item::Enum(ItemEnum { ident, .. })
             | Item::Union(ItemUnion { ident, .. })
             | Item::Const(ItemConst { ident, .. })
             | Item::Type(ItemType { ident, .. })
             | Item::Trait(ItemTrait { ident, .. })
+            | Item::TraitAlias(ItemTraitAlias { ident, .. })
             | Item::Macro(ItemMacro {
                 ident: Some(ident), ..
             })
             | Item::Macro2(ItemMacro2 { ident, .. })
             | Item::Static(ItemStatic { ident, .. })
-            | Item::Mod(ItemMod { ident, .. }) => {
+            | Item::Mod(ItemMod { ident, .. })
+            | Item::ExternCrate(ItemExternCrate { ident, .. }) => {
                 self.current_path.push(ident.to_string());
 
                 let should_retain = self.should_retain_item();
@@ -61,6 +66,11 @@ impl<'a> Visitor<'a> {
                 self.current_path.pop();
                 should_retain
             }
+            Item::ForeignMod(_) => true,
+            // We hope for the unused imports to show them all.
+            Item::Use(_) => true,
+            Item::Verbatim(_) => true,
+            #[deny(non_exhaustive_omitted_patterns)]
             _ => true,
         }
     }

src/processor/checker.rs

@@ -1,5 +1,7 @@
 use std::{borrow::Borrow, collections::BTreeSet, fmt::Debug, mem};
 
+use crate::Options;
+
 use self::worklist::Worklist;
 
 #[derive(Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
@@ -20,6 +22,7 @@ impl Debug for AstPath {
 #[derive(Debug)]
 pub(crate) struct PassController {
     state: PassControllerState,
+    pub(crate) options: Options,
 }
 
 #[derive(Debug)]
@@ -86,11 +89,12 @@ fn split_owned<T, From: IntoIterator<Item = T>, A: FromIterator<T>, B: FromItera
 }
 
 impl PassController {
-    pub fn new() -> Self {
+    pub fn new(options: Options) -> Self {
         Self {
             state: PassControllerState::InitialCollection {
                 candidates: Vec::new(),
             },
+            options,
         }
     }
 

src/processor/mod.rs

@@ -181,7 +181,7 @@ impl Minimizer {
         invalidated_files: &mut HashSet<&'file SourceFile>,
         changes: &mut Changes,
     ) -> Result<()> {
-        let mut checker = PassController::new();
+        let mut checker = PassController::new(self.options.clone());
         loop {
             let file_display = file.path.display();
             let mut change = file.try_change(changes)?;