refactor: derive rustc commit from toolchain, inline format args

cds-amal · cds-amal · commit d14cc18f7ea9 · 2026-03-10T18:21:20.000-04:00
Drop the [metadata] section from rust-toolchain.toml; the UI test
scripts now derive the rustc commit hash directly from the nightly
date via the Rust manifest. Also fixes clippy uninlined_format_args
warnings.
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
@@ -22,10 +22,31 @@ jobs:
           ref: ${{ github.event.pull_request.head.sha }}
           submodules: recursive
 
+      - name: Install yq
+        run: |
+          set -euo pipefail
+          YQ_VERSION="v4.52.4"
+          mkdir -p "$HOME/.local/bin"
+          wget -qO "$HOME/.local/bin/yq" \
+            "https://github.com/mikefarah/yq/releases/download/${YQ_VERSION}/yq_linux_amd64"
+          chmod +x "$HOME/.local/bin/yq"
+          echo "$HOME/.local/bin" >> $GITHUB_PATH
+
+      - name: 'Read nightly channel from rust-toolchain.toml'
+        id: toolchain-meta
+        run: |
+          set -euo pipefail
+          CHANNEL=$(yq -r '.toolchain.channel' rust-toolchain.toml)
+          if [ -z "$CHANNEL" ] || [ "$CHANNEL" = "null" ]; then
+            echo "::error::Could not read toolchain.channel from rust-toolchain.toml"
+            exit 1
+          fi
+          echo "channel=$CHANNEL" >> "$GITHUB_OUTPUT"
+
       - name: "Set up nightly Rust" # https://github.com/rust-lang/rustup/issues/3409
         uses: dtolnay/rust-toolchain@master
         with:
-          toolchain: nightly-2024-11-29 # Hardcoded version, same as is in the build.rs
+          toolchain: ${{ steps.toolchain-meta.outputs.channel }}
 
       - name: 'Build stable-mir-json' # rustfmt documentation claims it is unstable on code that doesn't build
         run: |
@@ -66,10 +87,31 @@ jobs:
           ref: ${{ github.event.pull_request.head.sha }}
           submodules: recursive
 
+      - name: Install yq
+        run: |
+          set -euo pipefail
+          YQ_VERSION="v4.52.4"
+          mkdir -p "$HOME/.local/bin"
+          wget -qO "$HOME/.local/bin/yq" \
+            "https://github.com/mikefarah/yq/releases/download/${YQ_VERSION}/yq_linux_amd64"
+          chmod +x "$HOME/.local/bin/yq"
+          echo "$HOME/.local/bin" >> $GITHUB_PATH
+
+      - name: 'Read nightly channel from rust-toolchain.toml'
+        id: toolchain-meta
+        run: |
+          set -euo pipefail
+          CHANNEL=$(yq -r '.toolchain.channel' rust-toolchain.toml)
+          if [ -z "$CHANNEL" ] || [ "$CHANNEL" = "null" ]; then
+            echo "::error::Could not read toolchain.channel from rust-toolchain.toml"
+            exit 1
+          fi
+          echo "channel=$CHANNEL" >> "$GITHUB_OUTPUT"
+
       - name: "Set up nightly Rust" # https://github.com/rust-lang/rustup/issues/3409
         uses: dtolnay/rust-toolchain@master
         with:
-          toolchain: nightly-2024-11-29 # Hardcoded version, same as is in the build.rs
+          toolchain: ${{ steps.toolchain-meta.outputs.channel }}
 
       - name: 'Build stable-mir-json'
         run: | # Warning check should be redundant since code-quality runs first
@@ -108,16 +150,30 @@ jobs:
             "https://github.com/mikefarah/yq/releases/download/${YQ_VERSION}/yq_linux_amd64"
           chmod +x "$HOME/.local/bin/yq"
           echo "$HOME/.local/bin" >> $GITHUB_PATH
-          yq --version
 
+      - name: 'Read nightly channel from rust-toolchain.toml'
+        id: toolchain-meta
+        run: |
+          set -euo pipefail
+          CHANNEL=$(yq -r '.toolchain.channel' rust-toolchain.toml)
+          if [ -z "$CHANNEL" ] || [ "$CHANNEL" = "null" ]; then
+            echo "::error::Could not read toolchain.channel from rust-toolchain.toml"
+            exit 1
+          fi
+          echo "channel=$CHANNEL" >> "$GITHUB_OUTPUT"
+
+      - name: "Set up nightly Rust" # https://github.com/rust-lang/rustup/issues/3409
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ steps.toolchain-meta.outputs.channel }}
 
-      - name: 'Read rustc commit from rust-toolchain.toml'
+      - name: 'Derive rustc commit and check out Rust repo'
         id: rustc-meta
         run: |
           set -euo pipefail
-          COMMIT=$(yq '.metadata.rustc-commit' rust-toolchain.toml)
-          if [ -z "$COMMIT" ] || [ "$COMMIT" = "null" ]; then
-            echo "::error::metadata.rustc-commit not found in rust-toolchain.toml"
+          COMMIT=$(rustc -vV | grep 'commit-hash' | cut -d' ' -f2)
+          if [ -z "$COMMIT" ]; then
+            echo "::error::Could not determine rustc commit-hash from 'rustc -vV'"
             exit 1
           fi
           echo "rustc-commit=$COMMIT" >> "$GITHUB_OUTPUT"
@@ -130,11 +186,6 @@ jobs:
           path: rust
           fetch-depth: 1
 
-      - name: "Set up nightly Rust" # https://github.com/rust-lang/rustup/issues/3409
-        uses: dtolnay/rust-toolchain@master
-        with:
-          toolchain: nightly-2024-11-29 # Hardcoded version, same as is in the build.rs
-
       - name: 'Build stable-mir-json'
         run: | # Warning check should be redundant since code-quality runs first
           RUSTFLAGS='--deny warnings' cargo build -vv
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
@@ -1,9 +1,3 @@
 [toolchain]
 channel = "nightly-2024-11-29"
 components = ["llvm-tools", "rustc-dev", "rust-src", "rust-analyzer"]
-
-# Ignored by rustup; used by our test scripts.
-# This is the rustc commit that backs the nightly above.
-# UI test scripts automatically checkout this commit in RUST_DIR_ROOT.
-[metadata]
-rustc-commit = "a2545fd6fc66b4323f555223a860c451885d1d2b"
diff --git a/src/printer/items.rs b/src/printer/items.rs
@@ -101,8 +101,7 @@ pub(super) fn mk_item(tcx: TyCtxt<'_>, item: MonoItem, sym_name: String) -> (Mon
                 Ok(alloc) => Some(alloc),
                 err => {
                     eprintln!(
-                        "StaticDef({:#?}).eval_initializer() failed with: {:#?}",
-                        static_def, err
+                        "StaticDef({static_def:#?}).eval_initializer() failed with: {err:#?}"
                     );
                     None
                 }
@@ -125,7 +124,7 @@ pub(super) fn mk_item(tcx: TyCtxt<'_>, item: MonoItem, sym_name: String) -> (Mon
             )
         }
         MonoItem::GlobalAsm(ref asm) => {
-            let asm_str = format!("{:#?}", asm);
+            let asm_str = format!("{asm:#?}");
             (
                 item,
                 Item::new(
diff --git a/src/printer/schema.rs b/src/printer/schema.rs
@@ -118,11 +118,10 @@ impl AllocMap {
 
         assert!(
             missing_from_map.is_empty(),
-            "Alloc-id coherence violation: AllocIds {:?} are referenced in \
+            "Alloc-id coherence violation: AllocIds {missing_from_map:?} are referenced in \
              stored Item bodies but missing from the alloc map. This means \
              the analysis phase collected allocations from a different body \
-             than what is stored in the Items.",
-            missing_from_map
+             than what is stored in the Items."
         );
 
         assert!(
diff --git a/tests/ui/ensure_rustc_commit.sh b/tests/ui/ensure_rustc_commit.sh
@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 #
 # Ensures a rust checkout (regular or bare+worktree) is at the commit
-# specified in rust-toolchain.toml's [metadata] rustc-commit field.
+# that backs the active nightly toolchain (derived from `rustc -vV`).
 #
 # Usage: source this script after setting RUST_DIR to the repo root.
 # It sets RUST_SRC_DIR to the directory containing the source files
@@ -11,21 +11,11 @@ set -u
 
 : "${RUST_DIR:?RUST_DIR must be set before sourcing ensure_rustc_commit.sh}"
 
-# Require yq (mikefarah/yq) for TOML parsing
-if ! command -v yq &> /dev/null; then
-    echo "Error: yq is required but not installed."
-    echo "Install via: brew install yq | apt install yq | nix shell nixpkgs#yq-go"
-    echo "See: https://github.com/mikefarah/yq#install"
-    exit 1
-fi
-
-_SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
-_REPO_ROOT=$( cd -- "$_SCRIPT_DIR/../.." &> /dev/null && pwd )
-
-# Read the expected rustc commit from rust-toolchain.toml
-RUSTC_COMMIT=$(yq -r '.metadata.rustc-commit' "$_REPO_ROOT/rust-toolchain.toml")
-if [ -z "$RUSTC_COMMIT" ] || [ "$RUSTC_COMMIT" = "null" ]; then
-    echo "Error: Could not read metadata.rustc-commit from $_REPO_ROOT/rust-toolchain.toml"
+# Derive the rustc commit from the active toolchain; rust-toolchain.toml
+# selects the nightly, so this stays in sync automatically.
+RUSTC_COMMIT=$(rustc -vV | grep 'commit-hash' | cut -d' ' -f2)
+if [ -z "$RUSTC_COMMIT" ]; then
+    echo "Error: Could not determine rustc commit-hash from 'rustc -vV'"
     exit 1
 fi
 
@@ -48,6 +38,16 @@ if [ "$IS_BARE" = "true" ]; then
             exit 1
         fi
     else
+        # Ensure the commit is available locally; fetch if needed.
+        if ! git -C "$RUST_DIR" cat-file -e "$RUSTC_COMMIT" 2>/dev/null; then
+            echo "Commit ${SHORT_COMMIT} not found locally; fetching..."
+            git -C "$RUST_DIR" fetch origin "$RUSTC_COMMIT" --quiet 2>/dev/null || \
+            git -C "$RUST_DIR" fetch origin --quiet || {
+                echo "Error: Could not fetch commit ${RUSTC_COMMIT}."
+                echo "Ensure ${RUST_DIR} is a clone of https://github.com/rust-lang/rust"
+                exit 1
+            }
+        fi
         echo "Creating worktree at ${WORKTREE_DIR} for commit ${SHORT_COMMIT}..."
         git -C "$RUST_DIR" worktree add "$WORKTREE_DIR" "$RUSTC_COMMIT" --detach --quiet || {
             echo "Error: Failed to create worktree for commit ${RUSTC_COMMIT} in ${RUST_DIR}"
@@ -59,6 +59,16 @@ else
     # Regular repo: checkout the commit directly
     CURRENT_COMMIT=$(git -C "$RUST_DIR" rev-parse HEAD 2>/dev/null)
     if [ "${CURRENT_COMMIT}" != "${RUSTC_COMMIT}" ]; then
+        # Ensure the commit is available locally; fetch if needed.
+        if ! git -C "$RUST_DIR" cat-file -e "$RUSTC_COMMIT" 2>/dev/null; then
+            echo "Commit ${SHORT_COMMIT} not found locally; fetching..."
+            git -C "$RUST_DIR" fetch origin "$RUSTC_COMMIT" --quiet 2>/dev/null || \
+            git -C "$RUST_DIR" fetch origin --quiet || {
+                echo "Error: Could not fetch commit ${RUSTC_COMMIT}."
+                echo "Ensure ${RUST_DIR} is a clone of https://github.com/rust-lang/rust"
+                exit 1
+            }
+        fi
         echo "Checking out rustc commit ${SHORT_COMMIT} in ${RUST_DIR}..."
         git -C "$RUST_DIR" checkout "$RUSTC_COMMIT" --quiet || {
             echo "Error: Failed to checkout commit ${RUSTC_COMMIT} in ${RUST_DIR}"

Original file line number	Diff line number	Diff line change
`@@ -101,8 +101,7 @@ pub(super) fn mk_item(tcx: TyCtxt<'_>, item: MonoItem, sym_name: String) -> (Mon`
`101`	`101`	`Ok(alloc) => Some(alloc),`
`102`	`102`	`err => {`
`103`	`103`	`eprintln!(`
`104`		`- "StaticDef({:#?}).eval_initializer() failed with: {:#?}",`
`105`		`- static_def, err`
	`104`	`+ "StaticDef({static_def:#?}).eval_initializer() failed with: {err:#?}"`
`106`	`105`	`);`
`107`	`106`	`None`
`108`	`107`	`}`
`@@ -125,7 +124,7 @@ pub(super) fn mk_item(tcx: TyCtxt<'_>, item: MonoItem, sym_name: String) -> (Mon`
`125`	`124`	`)`
`126`	`125`	`}`
`127`	`126`	`MonoItem::GlobalAsm(ref asm) => {`
`128`		`- let asm_str = format!("{:#?}", asm);`
	`127`	`+ let asm_str = format!("{asm:#?}");`
`129`	`128`	`(`
`130`	`129`	`item,`
`131`	`130`	`Item::new(`