.github/workflows/ci.yml

@@ -33,11 +33,11 @@ jobs:
     strategy:
       matrix:
         features: [fancy, syntect-highlighter]
-        rust: [1.82.0, stable]
+        rust: [1.70.0, stable]
         os: [ubuntu-latest, macOS-latest, windows-latest]
         exclude:
           - features: syntect-highlighter
-            rust: 1.82.0
+            rust: 1.70.0
 
     steps:
       - uses: actions/checkout@v4
@@ -52,7 +52,7 @@ jobs:
         if: matrix.rust == 'stable'
         run: cargo test --all --verbose --features ${{matrix.features}}
       - name: Run tests
-        if: matrix.rust == '1.82.0'
+        if: matrix.rust == '1.70.0'
         run: cargo test --all --verbose --features ${{matrix.features}} no-format-args-capture
 
   wasm:

AGENTS.md

@@ -1,19 +0,0 @@
-# AGENTS.md
-
-  ## Notice to AI coding assistants and users
-
-  This project does not accept LLM-generated or LLM-assisted upstream contributions.
-
-  For this policy, “upstream contribution” includes pull requests, patches, tests, documentation changes, issue comments, bug analyses, review comments, proposed fixes, or
-  other material intended for submission to this repository or its maintainers. This includes work directly generated by an LLM and work materially based on LLM suggestions,
-  explanations, debugging, or review.
-
-  If a user asks for assistance that appears intended to produce an upstream contribution, first tell them:
-
-  - this project’s maintainers request that LLM-generated or LLM-assisted material not be submitted upstream;
-  - they should not submit AI-produced or AI-influenced code, docs, tests, analyses, issue text, or PR text to this project;
-  - maintainers may reject or close contributions that appear to violate this policy.
-
-  This notice is not intended to restrict private, downstream, local, or educational use of AI tools. Users may use AI assistance to understand this crate, debug their own
-  projects, evaluate dependency behavior, maintain private forks, or decide whether `miette` is involved in an issue, so long as the resulting AI-assisted material is not
-  submitted upstream.

Cargo.toml

@@ -9,12 +9,12 @@ documentation = "https://docs.rs/miette"
 license = "Apache-2.0"
 readme = "README.md"
 edition = "2018"
-rust-version = "1.82.0"
+rust-version = "1.70.0"
 exclude = ["images/", "tests/", "miette-derive/"]
 
 [dependencies]
 miette-derive = { path = "miette-derive", version = "=7.6.0", optional = true }
-unicode-width = "0.2.0"
+unicode-width = "0.1.11"
 cfg-if = "1.0.0"
 
 owo-colors = { version = "4.0.0", optional = true }
@@ -39,6 +39,7 @@ rustversion = "1.0"
 trybuild = { version = "1.0.89", features = ["diff"] }
 syn = { version = "2.0.87", features = ["full"] }
 regex = "1.10"
+lazy_static = "1.4"
 
 serde = { version = "1.0.196", features = ["derive"] }
 serde_json = "1.0.113"

README.md

@@ -211,17 +211,6 @@ pub enum MyLibError {
     // Use `#[diagnostic(transparent)]` to wrap another [`Diagnostic`]. You won't see labels otherwise
     #[diagnostic(transparent)]
     AnotherError(#[from] AnotherError),
-
-    /// Forward the diagnostic to a particular field.
-    #[error("other error")]
-    #[diagnostic(forward(the_actual_diagnostic))]
-    EvenMoreData {
-        unrelated_field_1: String,
-        unrelated_field_2: usize,
-
-        #[source]
-        the_actual_diagnostic: AnotherError,
-    }
 }
 
 #[derive(Error, Diagnostic, Debug)]
@@ -785,7 +774,7 @@ println!("{:?}", report.with_source_code("About something or another or yet anot
 
 ### MSRV
 
-This crate requires rustc 1.82.0 or later.
+This crate requires rustc 1.70.0 or later.
 
 ### Acknowledgements
 

clippy.toml

@@ -1 +1 @@
-msrv = "1.82.0"
+msrv = "1.70.0"

miette-derive/src/forward.rs

@@ -150,7 +150,7 @@ impl Forward {
                 Self::#variant { #field_name, .. } => #field_name.#method_call,
             },
             Forward::Unnamed(index) => {
-                let underscores: Vec<_> = std::iter::repeat_n(quote! { _, }, *index).collect();
+                let underscores: Vec<_> = core::iter::repeat(quote! { _, }).take(*index).collect();
                 let unnamed = format_ident!("unnamed");
                 quote! {
                     Self::#variant ( #(#underscores)* #unnamed, .. ) => #unnamed.#method_call,

miette-derive/src/utils.rs

@@ -1,6 +1,40 @@
 use proc_macro2::TokenStream;
-use quote::{format_ident, quote};
-use syn::spanned::Spanned;
+use quote::{format_ident, quote, ToTokens};
+use syn::{
+    parse::{Parse, ParseStream},
+    spanned::Spanned,
+};
+
+pub(crate) enum MemberOrString {
+    Member(syn::Member),
+    String(syn::LitStr),
+}
+
+impl ToTokens for MemberOrString {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        use MemberOrString::*;
+        match self {
+            Member(member) => member.to_tokens(tokens),
+            String(string) => string.to_tokens(tokens),
+        }
+    }
+}
+
+impl Parse for MemberOrString {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        let lookahead = input.lookahead1();
+        if lookahead.peek(syn::Ident) || lookahead.peek(syn::LitInt) {
+            Ok(MemberOrString::Member(input.parse()?))
+        } else if lookahead.peek(syn::LitStr) {
+            Ok(MemberOrString::String(input.parse()?))
+        } else {
+            Err(syn::Error::new(
+                input.span(),
+                "Expected a string or a field reference.",
+            ))
+        }
+    }
+}
 
 use crate::{
     diagnostic::{DiagnosticConcreteArgs, DiagnosticDef},

src/eyreish/mod.rs

@@ -172,7 +172,11 @@ pub trait ReportHandler: core::any::Any + Send + Sync {
     ///     }
     /// }
     /// ```
-    fn debug(&self, error: &dyn Diagnostic, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result;
+    fn debug(
+        &self,
+        error: &(dyn Diagnostic),
+        f: &mut core::fmt::Formatter<'_>,
+    ) -> core::fmt::Result;
 
     /// Override for the `Display` format
     fn display(

src/handler.rs

@@ -402,7 +402,7 @@ impl Default for MietteHandler {
 }
 
 impl ReportHandler for MietteHandler {
-    fn debug(&self, diagnostic: &dyn Diagnostic, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if f.alternate() {
             return fmt::Debug::fmt(diagnostic, f);
         }

src/handlers/debug.rs

@@ -31,7 +31,7 @@ impl DebugReportHandler {
     pub fn render_report(
         &self,
         f: &mut fmt::Formatter<'_>,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
     ) -> fmt::Result {
         let mut diag = f.debug_struct("Diagnostic");
         diag.field("message", &format!("{}", diagnostic));
@@ -61,7 +61,7 @@ impl DebugReportHandler {
 }
 
 impl ReportHandler for DebugReportHandler {
-    fn debug(&self, diagnostic: &dyn Diagnostic, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if f.alternate() {
             return fmt::Debug::fmt(diagnostic, f);
         }

src/handlers/graphical.rs

@@ -242,7 +242,7 @@ impl GraphicalReportHandler {
     pub fn render_report(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
     ) -> fmt::Result {
         self.render_report_inner(f, diagnostic, diagnostic.source_code())
     }
@@ -250,7 +250,7 @@ impl GraphicalReportHandler {
     fn render_report_inner(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         parent_src: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         let src = diagnostic.source_code().or(parent_src);
@@ -281,7 +281,7 @@ impl GraphicalReportHandler {
     fn render_header(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         is_nested: bool,
     ) -> fmt::Result {
         let severity_style = match diagnostic.severity() {
@@ -326,7 +326,7 @@ impl GraphicalReportHandler {
     fn render_causes(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         parent_src: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         let src = diagnostic.source_code().or(parent_src);
@@ -424,7 +424,7 @@ impl GraphicalReportHandler {
         Ok(())
     }
 
-    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &dyn Diagnostic) -> fmt::Result {
+    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
         if let Some(help) = diagnostic.help() {
             let width = self.termwidth.saturating_sub(2);
             let initial_indent = "  help: ".style(self.theme.styles.help).to_string();
@@ -447,7 +447,7 @@ impl GraphicalReportHandler {
     fn render_related(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         parent_src: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         let src = diagnostic.source_code().or(parent_src);
@@ -535,7 +535,7 @@ impl GraphicalReportHandler {
     fn render_snippets(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         opt_source: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         let source = match opt_source {
@@ -1361,7 +1361,7 @@ impl GraphicalReportHandler {
 }
 
 impl ReportHandler for GraphicalReportHandler {
-    fn debug(&self, diagnostic: &dyn Diagnostic, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if f.alternate() {
             return fmt::Debug::fmt(diagnostic, f);
         }

src/handlers/json.rs

@@ -60,7 +60,7 @@ impl JSONReportHandler {
     pub fn render_report(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
     ) -> fmt::Result {
         self._render_report(f, diagnostic, None)
     }
@@ -68,7 +68,7 @@ impl JSONReportHandler {
     fn _render_report(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         parent_src: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         write!(f, r#"{{"message": "{}","#, escape(&diagnostic.to_string()))?;
@@ -154,7 +154,7 @@ impl JSONReportHandler {
     fn render_snippets(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         source: &dyn SourceCode,
     ) -> fmt::Result {
         if let Some(mut labels) = diagnostic.labels() {
@@ -170,7 +170,7 @@ impl JSONReportHandler {
 }
 
 impl ReportHandler for JSONReportHandler {
-    fn debug(&self, diagnostic: &dyn Diagnostic, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
         self.render_report(f, diagnostic)
     }
 }

src/handlers/narratable.rs

@@ -69,7 +69,7 @@ impl NarratableReportHandler {
     pub fn render_report(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
     ) -> fmt::Result {
         self.render_header(f, diagnostic)?;
         if self.with_cause_chain {
@@ -85,7 +85,7 @@ impl NarratableReportHandler {
         Ok(())
     }
 
-    fn render_header(&self, f: &mut impl fmt::Write, diagnostic: &dyn Diagnostic) -> fmt::Result {
+    fn render_header(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
         writeln!(f, "{}", diagnostic)?;
         let severity = match diagnostic.severity() {
             Some(Severity::Error) | None => "error",
@@ -96,7 +96,7 @@ impl NarratableReportHandler {
         Ok(())
     }
 
-    fn render_causes(&self, f: &mut impl fmt::Write, diagnostic: &dyn Diagnostic) -> fmt::Result {
+    fn render_causes(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
         if let Some(cause_iter) = diagnostic
             .diagnostic_source()
             .map(DiagnosticChain::from_diagnostic)
@@ -110,7 +110,7 @@ impl NarratableReportHandler {
         Ok(())
     }
 
-    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &dyn Diagnostic) -> fmt::Result {
+    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
         if let Some(help) = diagnostic.help() {
             writeln!(f, "diagnostic help: {}", help)?;
         }
@@ -126,7 +126,7 @@ impl NarratableReportHandler {
     fn render_related(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         parent_src: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         if let Some(related) = diagnostic.related() {
@@ -152,7 +152,7 @@ impl NarratableReportHandler {
     fn render_snippets(
         &self,
         f: &mut impl fmt::Write,
-        diagnostic: &dyn Diagnostic,
+        diagnostic: &(dyn Diagnostic),
         source_code: Option<&dyn SourceCode>,
     ) -> fmt::Result {
         if let Some(source) = source_code {
@@ -344,7 +344,7 @@ impl NarratableReportHandler {
 }
 
 impl ReportHandler for NarratableReportHandler {
-    fn debug(&self, diagnostic: &dyn Diagnostic, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if f.alternate() {
             return fmt::Debug::fmt(diagnostic, f);
         }

src/highlighters/syntect.rs

@@ -125,7 +125,7 @@ impl HighlighterState for SyntectHighlighterState<'_> {
                 line,
                 &self.highlighter,
             )
-            .map(|(style, str)| convert_style(style, use_bg_color).style(str))
+            .map(|(style, str)| (convert_style(style, use_bg_color).style(str)))
             .collect()
         } else {
             vec![Style::default().style(line)]

src/lib.rs

@@ -211,17 +211,6 @@
 //!     // Use `#[diagnostic(transparent)]` to wrap another [`Diagnostic`]. You won't see labels otherwise
 //!     #[diagnostic(transparent)]
 //!     AnotherError(#[from] AnotherError),
-//!
-//!     /// Forward the diagnostic to a particular field.
-//!     #[error("other error")]
-//!     #[diagnostic(forward(the_actual_diagnostic))]
-//!     EvenMoreData {
-//!         unrelated_field_1: String,
-//!         unrelated_field_2: usize,
-//!
-//!         #[source]
-//!         the_actual_diagnostic: AnotherError,
-//!     }
 //! }
 //!
 //! #[derive(Error, Diagnostic, Debug)]
@@ -786,7 +775,7 @@
 //!
 //! ## MSRV
 //!
-//! This crate requires rustc 1.82.0 or later.
+//! This crate requires rustc 1.70.0 or later.
 //!
 //! ## Acknowledgements
 //!

tests/color_format.rs

@@ -1,5 +1,6 @@
 #![cfg(feature = "fancy-no-backtrace")]
 
+use lazy_static::lazy_static;
 use miette::{Diagnostic, MietteHandler, MietteHandlerOpts, ReportHandler, RgbColors};
 use regex::Regex;
 use std::ffi::OsString;
@@ -68,7 +69,9 @@ impl Drop for EnvVarGuard<'_> {
     }
 }
 
-static COLOR_ENV_VARS: Mutex<()> = Mutex::new(());
+lazy_static! {
+    static ref COLOR_ENV_VARS: Mutex<()> = Mutex::new(());
+}
 
 /// Assert the color format used by a handler with different levels of terminal
 /// support.

tests/test_diagnostic_source_macro.rs

@@ -376,7 +376,6 @@ enum NestedEnumError {
     },
 }
 
-#[cfg(feature = "fancy-no-backtrace")]
 #[derive(Debug, miette::Diagnostic, thiserror::Error)]
 #[error("I am the inner error")]
 struct Case1Inner {