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use proc_macro2::{Span, TokenStream};
use crate::SpanDiagnosticExt;
use crate::line::Line;
pub trait MultiSpan {
fn into_spans(self) -> Vec<Span>;
}
impl MultiSpan for Span {
fn into_spans(self) -> Vec<Span> { vec![self] }
}
impl MultiSpan for Vec<Span> {
fn into_spans(self) -> Vec<Span> { self }
}
impl<'a> MultiSpan for &'a [Span] {
fn into_spans(self) -> Vec<Span> {
self.to_vec()
}
}
#[non_exhaustive]
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum Level {
Error,
Warning,
Note,
Help,
}
impl std::str::FromStr for Level {
type Err = ();
fn from_str(s: &str) -> Result<Self, Self::Err> {
if s.contains(Level::Error.as_str()) {
Ok(Level::Error)
} else if s.contains(Level::Warning.as_str()) {
Ok(Level::Warning)
} else if s.contains(Level::Note.as_str()) {
Ok(Level::Note)
} else if s.contains(Level::Help.as_str()) {
Ok(Level::Help)
} else {
Err(())
}
}
}
impl Level {
fn as_str(self) -> &'static str {
match self {
Level::Error => "error",
Level::Warning => "warning",
Level::Note => "note",
Level::Help => "help",
}
}
}
impl std::fmt::Display for Level {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
self.as_str().fmt(f)
}
}
#[derive(Clone, Debug)]
pub struct Diagnostic {
level: Level,
message: String,
spans: Vec<Span>,
children: Vec<Diagnostic>
}
macro_rules! diagnostic_child_methods {
($spanned:ident, $regular:ident, $level:expr) => (
pub fn $spanned<S, T>(self, spans: S, message: T) -> Diagnostic
where S: MultiSpan, T: Into<String>
{
self.spanned_child(spans, $level, message)
}
pub fn $regular<T: Into<String>>(self, message: T) -> Diagnostic {
self.child($level, message)
}
)
}
impl Diagnostic {
pub fn new<T: Into<String>>(level: Level, message: T) -> Diagnostic {
Diagnostic {
level,
message: message.into(),
spans: vec![],
children: vec![]
}
}
pub fn spanned<S, T>(spans: S, level: Level, message: T) -> Diagnostic
where S: MultiSpan, T: Into<String>
{
Diagnostic {
level,
message: message.into(),
spans: spans.into_spans(),
children: vec![]
}
}
pub fn spanned_child<S, T>(mut self, spans: S, level: Level, message: T) -> Diagnostic
where S: MultiSpan, T: Into<String>
{
self.children.push(Diagnostic::spanned(spans, level, message));
self
}
pub fn child<T: Into<String>>(mut self, level: Level, message: T) -> Diagnostic {
self.children.push(Diagnostic::new(level, message));
self
}
diagnostic_child_methods!(span_error, error, Level::Error);
diagnostic_child_methods!(span_warning, warning, Level::Warning);
diagnostic_child_methods!(span_note, note, Level::Note);
diagnostic_child_methods!(span_help, help, Level::Help);
pub fn children(&self) -> impl Iterator<Item=&Diagnostic> {
self.children.iter()
}
pub fn level(&self) -> Level {
self.level
}
fn stable_emit_as_tokens(self, item: bool) -> TokenStream {
let error: syn::parse::Error = self.into();
if item {
error.to_compile_error()
} else {
let compile_error_calls = error.into_iter().map(|e| {
let compile_error = e.to_compile_error();
quote::quote_spanned!(e.span() => #compile_error;)
});
quote::quote!({ #(#compile_error_calls)* })
}
}
#[cfg(not(nightly_diagnostics))]
fn emit_as_tokens(self, item: bool, _: TokenStream) -> TokenStream {
self.stable_emit_as_tokens(item)
}
#[cfg(nightly_diagnostics)]
fn emit_as_tokens(self, item: bool, default: TokenStream) -> TokenStream {
if !crate::nightly_works() {
return self.stable_emit_as_tokens(item);
}
proc_macro::Diagnostic::from(self).emit();
default
}
pub fn emit_as_item_tokens(self) -> TokenStream {
self.emit_as_tokens(true, TokenStream::new())
}
pub fn emit_as_item_tokens_or(self, default: TokenStream) -> TokenStream {
self.emit_as_tokens(true, default)
}
pub fn emit_as_expr_tokens(self) -> TokenStream {
self.emit_as_tokens(false, quote::quote!({}))
}
pub fn emit_as_expr_tokens_or(self, default: TokenStream) -> TokenStream {
self.emit_as_tokens(false, default)
}
}
impl From<Diagnostic> for syn::parse::Error {
fn from(diag: Diagnostic) -> syn::parse::Error {
fn diag_to_msg(diag: &Diagnostic) -> String {
let (spans, level, msg) = (&diag.spans, diag.level, &diag.message);
if spans.is_empty() {
Line::joined(level, msg).to_string()
} else {
if level == Level::Error {
return msg.into();
}
Line::new(level, msg).to_string()
}
}
fn diag_to_span(diag: &Diagnostic) -> Span {
diag.spans.get(0).cloned().unwrap_or_else(|| Span::call_site())
}
let mut msg = diag_to_msg(&diag);
let mut span = diag_to_span(&diag);
let mut error: Option<syn::Error> = None;
for child in diag.children {
if child.spans.is_empty() {
msg.push_str(&format!("\n {}", diag_to_msg(&child)));
} else {
let new_error = syn::parse::Error::new(span, &msg);
if let Some(ref mut error) = error {
error.combine(new_error);
} else {
error = Some(new_error);
}
span = diag_to_span(&child);
msg = diag_to_msg(&child);
}
}
if let Some(mut error) = error {
error.combine(syn::parse::Error::new(span, &msg));
error
} else {
syn::parse::Error::new(span, &msg)
}
}
}
impl From<syn::parse::Error> for Diagnostic {
fn from(error: syn::parse::Error) -> Diagnostic {
let mut diag: Option<Diagnostic> = None;
for e in &error {
for line in e.to_string().lines() {
if let Some(line) = Line::parse(line) {
if line.is_new() {
diag = diag.map(|d| d.spanned_child(e.span(), line.level, line.msg))
.or_else(|| Some(Diagnostic::spanned(e.span(), line.level, line.msg)));
} else {
diag = diag.map(|d| d.child(line.level, line.msg));
}
} else {
diag = diag.map(|d| d.span_error(e.span(), line))
.or_else(|| Some(e.span().error(line)));
}
}
}
diag.unwrap_or_else(|| error.span().error(error.to_string()))
}
}
#[cfg(nightly_diagnostics)]
impl From<Diagnostic> for proc_macro::Diagnostic {
fn from(diag: Diagnostic) -> proc_macro::Diagnostic {
fn spans_to_proc_macro_spans(spans: Vec<Span>) -> Vec<proc_macro::Span> {
spans.into_iter()
.map(|s| s.unstable())
.collect::<Vec<proc_macro::Span>>()
}
let spans = spans_to_proc_macro_spans(diag.spans);
let level = match diag.level {
Level::Error => proc_macro::Level::Error,
Level::Warning => proc_macro::Level::Warning,
Level::Note => proc_macro::Level::Note,
Level::Help => proc_macro::Level::Help,
};
let mut proc_diag = proc_macro::Diagnostic::spanned(spans, level, diag.message);
for child in diag.children {
let spans = spans_to_proc_macro_spans(child.spans);
proc_diag = match child.level {
Level::Error => proc_diag.span_error(spans, child.message),
Level::Warning => proc_diag.span_warning(spans, child.message),
Level::Note => proc_diag.span_note(spans, child.message),
Level::Help => proc_diag.span_help(spans, child.message),
};
}
proc_diag
}
}