Fix cargo doc Warnings (#14948)

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# Description
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As an avid `cargo doc` enjoyer I realized we had some doc warnings, so I
fixed them.

After this PR `cargo doc --workspace` should stop throwing warnings.
# User-Facing Changes
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helps us keep track of breaking changes. -->

No code changes.

# Tests + Formatting
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- `cargo fmt --all -- --check` to check standard code formatting (`cargo
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- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting
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We could add a `cargo doc` CI pipeline but usually running a full `cargo
doc` takes like forever, so maybe we don't want that.

crates/nu-plugin-core/src/serializers/mod.rs

@@ -12,7 +12,7 @@ mod tests;
 pub trait Encoder<T>: Clone + Send + Sync {
     /// Serialize a value in the [`PluginEncoder`]s format
     ///
-    /// Returns [`ShellError::IOError`] if there was a problem writing, or
+    /// Returns [`ShellError::Io`] if there was a problem writing, or
     /// [`ShellError::PluginFailedToEncode`] for a serialization error.
     fn encode(&self, data: &T, writer: &mut impl std::io::Write) -> Result<(), ShellError>;
 
@@ -20,7 +20,7 @@ pub trait Encoder<T>: Clone + Send + Sync {
     ///
     /// Returns `None` if there is no more output to receive.
     ///
-    /// Returns [`ShellError::IOError`] if there was a problem reading, or
+    /// Returns [`ShellError::Io`] if there was a problem reading, or
     /// [`ShellError::PluginFailedToDecode`] for a deserialization error.
     fn decode(&self, reader: &mut impl std::io::BufRead) -> Result<Option<T>, ShellError>;
 }

crates/nu-protocol/src/engine/engine_state.rs

@@ -609,7 +609,7 @@ impl EngineState {
         }
     }
 
-    /// Find the [`DeclId`](nu_protocol::id::DeclId) corresponding to a declaration with `name`.
+    /// Find the [`DeclId`](crate::DeclId) corresponding to a declaration with `name`.
     ///
     /// Searches within active overlays, and filtering out overlays in `removed_overlays`.
     pub fn find_decl(&self, name: &[u8], removed_overlays: &[Vec<u8>]) -> Option<DeclId> {
@@ -649,21 +649,21 @@ impl EngineState {
         None
     }
 
-    /// Find the [`OverlayId`](nu_protocol::id::OverlayId) corresponding to `name`.
+    /// Find the [`OverlayId`](crate::OverlayId) corresponding to `name`.
     ///
     /// Searches all overlays, not just active overlays. To search only in active overlays, use [`find_active_overlay`](EngineState::find_active_overlay)
     pub fn find_overlay(&self, name: &[u8]) -> Option<OverlayId> {
         self.scope.find_overlay(name)
     }
 
-    /// Find the [`OverlayId`](nu_protocol::id::OverlayId) of the active overlay corresponding to `name`.
+    /// Find the [`OverlayId`](crate::OverlayId) of the active overlay corresponding to `name`.
     ///
     /// Searches only active overlays. To search in all overlays, use [`find_overlay`](EngineState::find_active_overlay)
     pub fn find_active_overlay(&self, name: &[u8]) -> Option<OverlayId> {
         self.scope.find_active_overlay(name)
     }
 
-    /// Find the [`ModuleId`](nu_protocol::id::ModuleId) corresponding to `name`.
+    /// Find the [`ModuleId`](crate::ModuleId) corresponding to `name`.
     ///
     /// Searches within active overlays, and filtering out overlays in `removed_overlays`.
     pub fn find_module(&self, name: &[u8], removed_overlays: &[Vec<u8>]) -> Option<ModuleId> {

crates/nu-protocol/src/engine/state_working_set.rs

@@ -410,7 +410,7 @@ impl<'a> StateWorkingSet<'a> {
         self.delta.exit_scope();
     }
 
-    /// Find the [`DeclId`](nu_protocol::id::DeclId) corresponding to a predeclaration with `name`.
+    /// Find the [`DeclId`](crate::DeclId) corresponding to a predeclaration with `name`.
     pub fn find_predecl(&self, name: &[u8]) -> Option<DeclId> {
         let mut removed_overlays = vec![];
 
@@ -429,10 +429,11 @@ impl<'a> StateWorkingSet<'a> {
         None
     }
 
-    /// Find the [`DeclId`](nu_protocol::id::DeclId) corresponding to a declaration with `name`.
+    /// Find the [`DeclId`](crate::DeclId) corresponding to a declaration with `name`.
     ///
-    /// Extends [`EngineState::find_decl`] to also search for predeclarations (if [`StateWorkingSet::search_predecls`] is set),
-    /// and declarations from scopes existing only in [`StateDelta`].
+    /// Extends [`EngineState::find_decl`] to also search for predeclarations
+    /// (if [`StateWorkingSet::search_predecls`] is set), and declarations from scopes existing
+    /// only in [`StateDelta`].
     pub fn find_decl(&self, name: &[u8]) -> Option<DeclId> {
         let mut removed_overlays = vec![];
 
@@ -516,7 +517,7 @@ impl<'a> StateWorkingSet<'a> {
             .find_decl_name(decl_id, &removed_overlays)
     }
 
-    /// Find the [`ModuleId`](nu_protocol::id::ModuleId) corresponding to `name`.
+    /// Find the [`ModuleId`](crate::ModuleId) corresponding to `name`.
     ///
     /// Extends [`EngineState::find_module`] to also search for ,
     /// and declarations from scopes existing only in [`StateDelta`].

crates/nu-protocol/src/errors/shell_error/io.rs

@@ -256,9 +256,10 @@ impl IoError {
 
     /// Creates a new `IoError` for internal I/O errors with a specific path.
     ///
-    /// This constructor is similar to [`new_internal`] but also includes a file or directory
-    /// path relevant to the error. Use this function in rare cases where an internal error
-    /// involves a specific path, and the combination of path and additional context is helpful.
+    /// This constructor is similar to [`new_internal`](Self::new_internal) but also includes a
+    /// file or directory path relevant to the error.
+    /// Use this function in rare cases where an internal error involves a specific path, and the
+    /// combination of path and additional context is helpful.
     ///
     /// # Examples
     /// ```rust

crates/nu-protocol/src/pipeline/pipeline_data.rs

@@ -126,7 +126,7 @@ impl PipelineData {
     /// Determine if the `PipelineData` is a [subtype](https://en.wikipedia.org/wiki/Subtyping) of `other`.
     ///
     /// This check makes no effort to collect a stream, so it may be a different result
-    /// than would be returned by calling [`Value::is_subtype()`] on the result of
+    /// than would be returned by calling [`Value::is_subtype_of()`] on the result of
     /// [`.into_value()`](Self::into_value).
     ///
     /// A `ListStream` acts the same as an empty list type: it is a subtype of any [`list`](Type::List)

crates/nu-protocol/src/span.rs

@@ -224,8 +224,9 @@ impl From<Span> for SourceSpan {
 
 /// An extension trait for [`Result`], which adds a span to the error type.
 ///
-/// This trait might be removed later, since the old [`Spanned<std::io::Error>`] to [`ShellError`]
-/// conversion was replaced by [`IoError`](io_error::IoError).
+/// This trait might be removed later, since the old [`Spanned<std::io::Error>`] to
+/// [`ShellError`](crate::ShellError) conversion was replaced by
+/// [`IoError`](crate::shell_error::io::IoError).
 pub trait ErrSpan {
     type Result;
 

crates/nu-protocol/src/ty.rs

@@ -49,8 +49,9 @@ impl Type {
 
     /// Determine of the [`Type`] is a [subtype](https://en.wikipedia.org/wiki/Subtyping) of `other`.
     ///
-    /// This should only be used at parse-time. If you have a concrete [`Value`](crate::Value) or [`PipelineData`](crate::PipelineData),
-    /// you should use their respective [`is_subtype_of`] methods instead.
+    /// This should only be used at parse-time.
+    /// If you have a concrete [`Value`](crate::Value) or [`PipelineData`](crate::PipelineData),
+    /// you should use their respective `is_subtype_of` methods instead.
     pub fn is_subtype_of(&self, other: &Type) -> bool {
         // Structural subtyping
         let is_subtype_collection = |this: &[(String, Type)], that: &[(String, Type)]| {

crates/nu-protocol/src/value/mod.rs

@@ -820,7 +820,7 @@ impl Value {
     /// This method is able to leverage that information encoded in a `Value` to provide more accurate
     /// type comparison than if one were to collect the type into [`Type`](crate::Type) value with [`Value::get_type`].
     ///
-    /// Empty lists are considered subtypes of all list<T> types.
+    /// Empty lists are considered subtypes of all `list<T>` types.
     ///
     /// Lists of mixed records where some column is present in all record is a subtype of `table<column>`.
     /// For example, `[{a: 1, b: 2}, {a: 1}]` is a subtype of `table<a: int>` (but not `table<a: int, b: int>`).