From 0e1123b0ce814632d131da3b6e9849d71c7512b4 Mon Sep 17 00:00:00 2001
From: nori li <50680474+thenorili@users.noreply.github.com>
Date: Sat, 18 Nov 2023 23:19:21 -0800
Subject: [PATCH] Support unstable-less nightly

This change attempts to put unstable features behind an opt-in feature
flag as requested by issue #120. Unstable lints and compile_test.rs are
both gated by this feature which is added unconditionally to all CI
that touches more than just stable.

As expressed in issue #120, I have some concerns about *needing* to gate
compile_test.rs behind feature = "unstable". I'm not certain that this
unstable-less nightly eyre will work in production due to the reason
that compile_test.rs fails: three of our dependencies, anyhow,
thiserror, and proc-macro, all use a test for a nightly toolchain to
gate unstable features. Maybe I'm wrong though and this change is
sufficient!
---
 .github/workflows/ci.yml   | 6 +++---
 color-spantrace/Cargo.toml | 6 ++++++
 color-spantrace/src/lib.rs | 2 +-
 eyre/Cargo.toml            | 1 +
 eyre/src/lib.rs            | 2 +-
 eyre/tests/compiletest.rs  | 2 +-
 6 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c0d6919..cd8db8c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,9 +44,9 @@ jobs:
         features:
           - # default
           - --no-default-features
-          - --features track-caller
-          - --features pyo3
-          - --features auto-install
+          - --features unstable track-caller
+          - --features unstable pyo3
+          - --features unstable auto-install
           - --all-features
     steps:
       - uses: actions/checkout@v1
diff --git a/color-spantrace/Cargo.toml b/color-spantrace/Cargo.toml
index e1510d8..9d89d8c 100644
--- a/color-spantrace/Cargo.toml
+++ b/color-spantrace/Cargo.toml
@@ -11,6 +11,12 @@ repository = { workspace = true }
 readme = { workspace = true }
 rust-version = { workspace = true }
 
+[features]
+default = ["auto-install", "track-caller"]
+auto-install = []
+track-caller = []
+unstable = []
+
 [dependencies]
 tracing-error = "0.2.0"
 tracing-core = "0.1.21"
diff --git a/color-spantrace/src/lib.rs b/color-spantrace/src/lib.rs
index 6b07a34..e7ace85 100644
--- a/color-spantrace/src/lib.rs
+++ b/color-spantrace/src/lib.rs
@@ -61,7 +61,7 @@
 //! [`color-backtrace`]: https://github.com/athre0z/color-backtrace
 #![doc(html_root_url = "https://docs.rs/color-spantrace/0.2.0")]
 #![cfg_attr(
-    nightly,
+    all(nightly, feature = "unstable"),
     feature(rustdoc_missing_doc_code_examples),
     warn(rustdoc::missing_doc_code_examples)
 )]
diff --git a/eyre/Cargo.toml b/eyre/Cargo.toml
index 982d9b2..717eecc 100644
--- a/eyre/Cargo.toml
+++ b/eyre/Cargo.toml
@@ -16,6 +16,7 @@ rust-version = { workspace = true }
 default = ["auto-install", "track-caller"]
 auto-install = []
 track-caller = []
+unstable = []
 
 [dependencies]
 indenter = { workspace = true }
diff --git a/eyre/src/lib.rs b/eyre/src/lib.rs
index f56640a..0cf7df1 100644
--- a/eyre/src/lib.rs
+++ b/eyre/src/lib.rs
@@ -316,7 +316,7 @@
 //! [`color-backtrace`]: https://github.com/athre0z/color-backtrace
 #![doc(html_root_url = "https://docs.rs/eyre/0.6.8")]
 #![cfg_attr(
-    nightly,
+    all(nightly, feature = "unstable"),
     feature(rustdoc_missing_doc_code_examples),
     warn(rustdoc::missing_doc_code_examples)
 )]
diff --git a/eyre/tests/compiletest.rs b/eyre/tests/compiletest.rs
index 7974a62..303e8d6 100644
--- a/eyre/tests/compiletest.rs
+++ b/eyre/tests/compiletest.rs
@@ -1,4 +1,4 @@
-#[rustversion::attr(not(nightly), ignore)]
+#[cfg_attr(any(not(nightly), not(feature = "unstable")), ignore)]
 #[cfg_attr(miri, ignore)]
 #[test]
 fn ui() {