Refactor config updates (#13802)

# Description
This PR standardizes updates to the config through a new
`UpdateFromValue` trait. For now, this trait is private in case we need
to make changes to it.

Note that this PR adds some additional `ShellError` cases to create
standard error messages for config errors. A follow-up PR will move
usages of the old error cases to these new ones. This PR also uses
`Type::custom` in lots of places (e.g., for string enums). Not sure if
this is something we want to encourage.

# User-Facing Changes
Should be none.

crates/nu-protocol/src/errors/cli_error.rs

@@ -15,8 +15,8 @@ use thiserror::Error;
 /// forwards most methods, except for `.source_code()`, which we provide.
 #[derive(Error)]
 #[error("{0}")]
-pub struct CliError<'src>(
-    pub &'src (dyn miette::Diagnostic + Send + Sync + 'static),
+struct CliError<'src>(
+    pub &'src dyn miette::Diagnostic,
     pub &'src StateWorkingSet<'src>,
 );
 
@@ -48,10 +48,7 @@ pub fn report_compile_error(working_set: &StateWorkingSet, error: &CompileError)
     report_error(working_set, error);
 }
 
-fn report_error(
-    working_set: &StateWorkingSet,
-    error: &(dyn miette::Diagnostic + Send + Sync + 'static),
-) {
+fn report_error(working_set: &StateWorkingSet, error: &dyn miette::Diagnostic) {
     eprintln!("Error: {:?}", CliError(error, working_set));
     // reset vt processing, aka ansi because illbehaved externals can break it
     #[cfg(windows)]
@@ -60,10 +57,7 @@ fn report_error(
     }
 }
 
-fn report_warning(
-    working_set: &StateWorkingSet,
-    error: &(dyn miette::Diagnostic + Send + Sync + 'static),
-) {
+fn report_warning(working_set: &StateWorkingSet, error: &dyn miette::Diagnostic) {
     eprintln!("Warning: {:?}", CliError(error, working_set));
     // reset vt processing, aka ansi because illbehaved externals can break it
     #[cfg(windows)]

crates/nu-protocol/src/errors/config_error.rs

@@ -0,0 +1,56 @@
+use crate::{ShellError, Span, Type};
+use miette::Diagnostic;
+use thiserror::Error;
+
+/// The errors that may occur when updating the config
+#[derive(Clone, Debug, PartialEq, Error, Diagnostic)]
+pub enum ConfigError {
+    #[error("Type mismatch at {path}")]
+    #[diagnostic(code(nu::shell::type_mismatch))]
+    TypeMismatch {
+        path: String,
+        expected: Type,
+        actual: Type,
+        #[label = "expected {expected}, but got {actual}"]
+        span: Span,
+    },
+    #[error("Invalid value for {path}")]
+    #[diagnostic(code(nu::shell::invalid_value))]
+    InvalidValue {
+        path: String,
+        valid: String,
+        actual: String,
+        #[label = "expected {valid}, but got {actual}"]
+        span: Span,
+    },
+    #[error("Unknown config option: {path}")]
+    #[diagnostic(code(nu::shell::unknown_config_option))]
+    UnknownOption {
+        path: String,
+        #[label("remove this")]
+        span: Span,
+    },
+    #[error("{path} requires a '{column}' column")]
+    #[diagnostic(code(nu::shell::missing_required_column))]
+    MissingRequiredColumn {
+        path: String,
+        column: &'static str,
+        #[label("has no '{column}' column")]
+        span: Span,
+    },
+    #[error("{path} is deprecated")]
+    #[diagnostic(
+        code(nu::shell::deprecated_config_option),
+        help("please {suggestion} instead")
+    )]
+    Deprecated {
+        path: String,
+        suggestion: &'static str,
+        #[label("deprecated")]
+        span: Span,
+    },
+    // TODO: remove this
+    #[error(transparent)]
+    #[diagnostic(transparent)]
+    ShellError(#[from] ShellError),
+}

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

@@ -1,5 +1,6 @@
 pub mod cli_error;
 mod compile_error;
+mod config_error;
 mod labeled_error;
 mod parse_error;
 mod parse_warning;
@@ -10,6 +11,7 @@ pub use cli_error::{
     report_shell_warning,
 };
 pub use compile_error::CompileError;
+pub use config_error::ConfigError;
 pub use labeled_error::{ErrorLabel, LabeledError};
 pub use parse_error::{DidYouMean, ParseError};
 pub use parse_warning::ParseWarning;

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

@@ -1,13 +1,12 @@
+use crate::{
+    ast::Operator, engine::StateWorkingSet, format_shell_error, record, ConfigError, LabeledError,
+    ParseError, Span, Spanned, Type, Value,
+};
 use miette::Diagnostic;
 use serde::{Deserialize, Serialize};
 use std::{io, num::NonZeroI32};
 use thiserror::Error;
 
-use crate::{
-    ast::Operator, engine::StateWorkingSet, format_shell_error, record, LabeledError, ParseError,
-    Span, Spanned, Value,
-};
-
 /// The fundamental error type for the evaluation engine. These cases represent different kinds of errors
 /// the evaluator might face, along with helpful spans to label. An error renderer will take this error value
 /// and pass it into an error viewer to display to the user.
@@ -108,6 +107,34 @@ pub enum ShellError {
         span: Span,
     },
 
+    /// A value's type did not match the expected type.
+    ///
+    /// ## Resolution
+    ///
+    /// Convert the value to the correct type or provide a value of the correct type.
+    #[error("Type mismatch")]
+    #[diagnostic(code(nu::shell::type_mismatch))]
+    RuntimeTypeMismatch {
+        expected: Type,
+        actual: Type,
+        #[label = "expected {expected}, but got {actual}"]
+        span: Span,
+    },
+
+    /// A value had the correct type but is otherwise invalid.
+    ///
+    /// ## Resolution
+    ///
+    /// Ensure the value meets the criteria in the error message.
+    #[error("Invalid value")]
+    #[diagnostic(code(nu::shell::invalid_value))]
+    InvalidValue {
+        valid: String,
+        actual: String,
+        #[label = "expected {valid}, but got {actual}"]
+        span: Span,
+    },
+
     /// A command received an argument with correct type but incorrect value.
     ///
     /// ## Resolution
@@ -1085,30 +1112,28 @@ pub enum ShellError {
         span: Span,
     },
 
-    /// The value given for this configuration is not supported.
+    /// Failed to update the config due to one or more errors.
     ///
     /// ## Resolution
     ///
-    /// Refer to the specific error message for details and convert values as needed.
-    #[error("Unsupported config value")]
-    #[diagnostic(code(nu::shell::unsupported_config_value))]
-    UnsupportedConfigValue {
-        expected: String,
-        value: String,
-        #[label("expected {expected}, got {value}")]
-        span: Span,
+    /// Refer to the error messages for specific details.
+    #[error("Encountered {} error(s) when updating config", errors.len())]
+    #[diagnostic(code(nu::shell::invalid_config))]
+    InvalidConfig {
+        #[related]
+        errors: Vec<ConfigError>,
     },
 
-    /// An expected configuration value is not present.
+    /// A value was missing a required column.
     ///
     /// ## Resolution
     ///
-    /// Refer to the specific error message and add the configuration value to your config file as needed.
-    #[error("Missing config value")]
-    #[diagnostic(code(nu::shell::missing_config_value))]
-    MissingConfigValue {
-        missing_value: String,
-        #[label("missing {missing_value}")]
+    /// Make sure the value has the required column.
+    #[error("Value is missing a required '{column}' column")]
+    #[diagnostic(code(nu::shell::missing_required_column))]
+    MissingRequiredColumn {
+        column: &'static str,
+        #[label("has no '{column}' column")]
         span: Span,
     },