From 25f03960e1fb7162215549fe7fa613d04ee4693b Mon Sep 17 00:00:00 2001
From: Jim Blandy <jimb@red-bean.com>
Date: Wed, 9 Apr 2025 12:58:44 -0700
Subject: [PATCH] [naga] Delete `DiagnosticDisplay` impl for for `TypeInner`.
Delete the implementation of `core::fmt::Display` for
`naga::common::DiagnosticDisplay`, as it is a footgun wherever
`Struct` types can arise.
Document that it should not be implemented for `TypeInner`.
Although it is possible to put a dummy implementation in the way of
people adding real implementations, that would also turn attempts to
use it into dynamic errors rather than compile-time errors. Make do
with a comment for now.
---
naga/src/common/diagnostic_display.rs | 24 +++++-------------------
1 file changed, 5 insertions(+), 19 deletions(-)
diff --git a/naga/src/common/diagnostic_display.rs b/naga/src/common/diagnostic_display.rs
index 06164a536..2713d5a0e 100644
--- a/naga/src/common/diagnostic_display.rs
+++ b/naga/src/common/diagnostic_display.rs
@@ -1,7 +1,7 @@
//! Displaying Naga IR terms in diagnostic output.
use crate::proc::{GlobalCtx, Rule, TypeResolution};
-use crate::{Handle, Scalar, Type, TypeInner};
+use crate::{Handle, Scalar, Type};
#[cfg(any(feature = "wgsl-in", feature = "wgsl-out"))]
use crate::common::wgsl::TypeContext;
@@ -23,13 +23,16 @@ use core::fmt;
/// for a type like `DiagnosticDisplay<(Handle<Type>, GlobalCtx)>`, where
/// the [`GlobalCtx`] type provides the necessary context.
///
+/// Do not implement this type for [`TypeInner`], as that does not
+/// have enough information to display struct types correctly.
+///
/// If you only need debugging output, [`DiagnosticDebug`] uses
/// easier-to-obtain context types but still does a good enough job
/// for logging or debugging.
///
/// [`Display`]: core::fmt::Display
-/// [`Scalar`]: crate::Scalar
/// [`GlobalCtx`]: crate::proc::GlobalCtx
+/// [`TypeInner`]: crate::ir::TypeInner
/// [`DiagnosticDebug`]: super::DiagnosticDebug
///
/// ## Language-sensitive diagnostics
@@ -83,23 +86,6 @@ impl fmt::Display for DiagnosticDisplay<(Handle<Type>, GlobalCtx<'_>)> {
}
}
-impl fmt::Display for DiagnosticDisplay<(&TypeInner, GlobalCtx<'_>)> {
- fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
- let (inner, ref ctx) = self.0;
-
- #[cfg(any(feature = "wgsl-in", feature = "wgsl-out"))]
- ctx.write_type_inner(inner, f)?;
-
- #[cfg(not(any(feature = "wgsl-in", feature = "wgsl-out")))]
- {
- let _ = ctx;
- write!(f, "{inner:?}")?;
- }
-
- Ok(())
- }
-}
-
impl fmt::Display for DiagnosticDisplay<(&str, &Rule, GlobalCtx<'_>)> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let (name, rule, ref ctx) = self.0;