BE-640: Fix cargo unused_dependencies warnings and surface them in CI

.github/workflows/lint.yml

@@ -136,17 +136,29 @@ jobs:
 
       - name: Run clippy
         if: always() && steps.lints.outputs.clippy == 'true'
+        # `bash` gives us `pipefail`, so a failing `turbo`/`clippy` fails the step instead of
+        # being masked by a later pipeline stage exiting 0.
+        shell: bash
         run: |
           pushd ${{ matrix.path }}
           turbo run lint:clippy --filter "${{ matrix.name }}" -- --message-format=json \
+            | tee clippy-output.log \
             | clippy-sarif \
             | jq --arg path "${{ matrix.path }}" '.runs[].results |= map(select(.locations[].physicalLocation.artifactLocation.uri | startswith($path)))' \
             | jq '.runs[].results |= unique' \
             > clippy.sarif
           popd
           cat ${{ matrix.path }}/clippy.sarif | sarif-fmt
-
-          jq -e '.runs[].results == []' ${{ matrix.path }}/clippy.sarif> /dev/null
+          jq -e '.runs[].results == []' ${{ matrix.path }}/clippy.sarif > /dev/null
+
+          # Cargo's manifest lints (e.g. `cargo::unused_dependencies`) are plain text, not compiler
+          # JSON, so they bypass the SARIF gate above and were consumed by the pipeline. Re-print
+          # the human-readable output (dropping JSON) and fail on the package-level lint. The
+          # workspace-level variant is ignored: it false-positives in the pruned per-package repo.
+          if grep -qF "warning: unused dependency" ${{ matrix.path }}/clippy-output.log; then
+            grep -vF '{"reason":' ${{ matrix.path }}/clippy-output.log
+            exit 1
+          fi
 
       - name: Print clippy errors to summary
         if: failure() && steps.lints.outputs.clippy == 'true'

Cargo.toml

@@ -216,7 +216,6 @@ postgres-types                     = { version = "0.2.11", default-features = fa
 pretty                             = { version = "0.12.5", default-features = false }
 pretty_assertions                  = { version = "1.4.1", default-features = false, features = ["alloc"] }
 prettyplease                       = { version = "0.2.37", default-features = false }
-proc-macro-error2                  = { version = "2.0.1", default-features = false }
 proc-macro2                        = { version = "1.0.103", default-features = false }
 prometheus-client                  = { version = "0.24.0", default-features = false }
 proptest                           = { version = "1.7.0", default-features = false, features = ["alloc", "std"] }                                                                                  # `std` or `no_std` are required, `no_std` pulls in `libm`

apps/hash-graph/src/main.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![forbid(unsafe_code)]
 #![expect(
     unreachable_pub,

libs/@blockprotocol/type-system/rust/Cargo.toml

@@ -35,7 +35,6 @@ uuid             = { workspace = true, public = true, features = ["v5", "serde",
 
 # Private third-party dependencies
 derive_more    = { workspace = true, features = ["display", "error", "from"] }
-futures        = { workspace = true }
 itertools      = { workspace = true, features = ["use_alloc"] }
 regex          = { workspace = true, features = ["std"] }
 serde          = { workspace = true, features = ["derive", "rc"] }

libs/@blockprotocol/type-system/rust/src/lib.rs

@@ -336,7 +336,7 @@
 //! - `utoipa` - Enables OpenAPI schema generation
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 
 extern crate alloc;
 

libs/@local/codec/Cargo.toml

@@ -13,7 +13,7 @@ harpc-wire-protocol = { workspace = true, public = true, optional = true }
 postgres-types      = { workspace = true, public = true, optional = true }
 
 # Public third-party dependencies
-bytes      = { workspace = true, public = true }
+bytes      = { workspace = true, public = true, optional = true }
 regex      = { workspace = true, public = true, optional = true }
 serde_core = { workspace = true, public = true, optional = true }
 specta     = { workspace = true, public = true, optional = true, features = ["derive"] }
@@ -45,15 +45,19 @@ name              = "codegen"
 required-features = ["codegen", "numeric"]
 
 [features]
-codegen = ["dep:specta"]
 bytes = [
+    "dep:bytes",
     "dep:serde_core",
     "dep:serde",
     "dep:derive-where",
     "dep:serde_json",
     "dep:tokio-util",
     "dep:error-stack",
 ]
+codegen = ["dep:specta"]
+harpc = ["dep:bytes", "dep:harpc-wire-protocol", "dep:tokio-util", "dep:error-stack"]
+numeric = ["dep:dashu-base", "dep:dashu-float", "dep:derive_more"]
+postgres = ["dep:bytes", "dep:postgres-types"]
 serde = [
     "dep:serde_core",
     "dep:serde",
@@ -62,9 +66,6 @@ serde = [
     "dep:uuid",
     "dep:derive_more",
 ]
-harpc = ["dep:harpc-wire-protocol", "dep:tokio-util", "dep:error-stack"]
-numeric = ["dep:dashu-base", "dep:dashu-float", "dep:derive_more"]
-postgres = ["dep:postgres-types"]
 utoipa = ["dep:utoipa"]
 
 [lints]

libs/@local/codec/src/lib.rs

@@ -1,10 +1,31 @@
 #![cfg_attr(doc, doc = include_str!("../README.md"))]
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 
 extern crate alloc;
 
+// `postgres` and `utoipa` pull `postgres-types`/`bytes` and `utoipa`, but those are only consumed
+// by the `Real` integration in the `numeric` module, i.e. at the *intersection* of `numeric` and
+// the respective feature. Cargo activates a dependency on the feature *union*, so enabling one
+// side without `numeric` pulls the dependency without compiling a user of it. Anchor those
+// combinations so `cargo::unused_dependencies` (checked across the merge-queue powerset) stays
+// quiet.
+// `bytes` is additionally pulled by `postgres` (for the `Real` `ToSql` impl), but also used
+// directly by the `bytes` and `harpc` modules. Only anchor it when none of its consumers
+// compile.
+#[cfg(all(
+    feature = "postgres",
+    not(feature = "numeric"),
+    not(feature = "bytes"),
+    not(feature = "harpc")
+))]
+use bytes as _;
+#[cfg(all(feature = "postgres", not(feature = "numeric")))]
+use postgres_types as _;
+#[cfg(all(feature = "utoipa", not(feature = "numeric")))]
+use utoipa as _;
+
 #[cfg(feature = "bytes")]
 pub mod bytes;
 #[cfg(feature = "harpc")]

libs/@local/codegen/src/lib.rs

@@ -3,7 +3,7 @@
 //! Code generation utilities for the HASH ecosystem.
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![expect(clippy::todo)]
 
 use alloc::{borrow::Cow, collections::BTreeSet};

libs/@local/effect-dns/hickory/src/lib.rs

@@ -1,7 +1,7 @@
 //! # Effect-DNS Hickory
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![allow(clippy::cfg_not_test, reason = "napi macro uses cfg(not(test))")]
 
 use napi_derive::napi;

libs/@local/graph/api/Cargo.toml

@@ -68,7 +68,6 @@ md-5                               = { workspace = true }
 mime                               = { workspace = true }
 opentelemetry                      = { workspace = true }
 opentelemetry-semantic-conventions = { workspace = true, features = ["semconv_experimental"] }
-opentelemetry_sdk                  = { workspace = true, features = ["rt-tokio"] }
 reqwest                            = { workspace = true }
 sentry                             = { workspace = true }
 serde                              = { workspace = true, features = ['derive'] }

libs/@local/graph/api/src/lib.rs

@@ -1,6 +1,6 @@
 #![cfg_attr(doc, doc = include_str!("../README.md"))]
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![feature(
     // Language Features
     impl_trait_in_assoc_type,

libs/@local/graph/authorization/Cargo.toml

@@ -12,9 +12,7 @@ error-stack = { workspace = true, public = true, features = ["unstable"] }
 type-system = { workspace = true, public = true }
 
 # Public third-party dependencies
-futures-core   = { workspace = true, public = true }
 postgres-types = { workspace = true, public = true, features = ["derive", "with-uuid-1"], optional = true }
-reqwest        = { workspace = true, public = true, features = ["json", "stream"] }
 specta         = { workspace = true, public = true, optional = true, features = ["derive"] }
 
 # Private workspace dependencies
@@ -26,7 +24,6 @@ cedar-policy-core = { workspace = true }
 derive-where      = { workspace = true }
 derive_more       = { workspace = true, features = ["display", "error", "from"] }
 enum-iterator     = { workspace = true }
-futures           = { workspace = true }
 serde             = { workspace = true, features = ["derive", "unstable"] }
 serde_json        = { workspace = true }
 serde_plain       = { workspace = true }

libs/@local/graph/authorization/src/lib.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph Authorization
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![feature(
     // Language Features
     exhaustive_patterns,

libs/@local/graph/migrations-macros/Cargo.toml

@@ -13,16 +13,15 @@ proc-macro = true
 # Workspace dependencies
 
 # Third-party dependencies
-convert_case      = { workspace = true }
-derive_more       = { workspace = true, features = ["display", "error", "from"] }
-proc-macro-error2 = { workspace = true }
-proc-macro2       = { workspace = true }
-quote             = { workspace = true }
-regex             = { workspace = true }
-sha2              = { workspace = true }
-simple-mermaid    = { workspace = true }
-syn               = { workspace = true }
-walkdir           = { workspace = true }
+convert_case   = { workspace = true }
+derive_more    = { workspace = true, features = ["display", "error", "from"] }
+proc-macro2    = { workspace = true }
+quote          = { workspace = true }
+regex          = { workspace = true }
+sha2           = { workspace = true }
+simple-mermaid = { workspace = true }
+syn            = { workspace = true }
+walkdir        = { workspace = true }
 
 [lints]
 workspace = true

libs/@local/graph/migrations-macros/src/lib.rs

@@ -1,6 +1,6 @@
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 
 extern crate alloc;
 

libs/@local/graph/migrations/src/lib.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph Migrations
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![feature(
     // Language Features
     impl_trait_in_assoc_type,

libs/@local/graph/postgres-store/src/lib.rs

@@ -1,7 +1,7 @@
 //! The entity-graph query-layer for the HASH datastore.
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![feature(
     // Language Features
     impl_trait_in_assoc_type,

libs/@local/graph/store/Cargo.toml

@@ -14,6 +14,7 @@ hash-graph-types         = { workspace = true, public = true }
 hash-temporal-client     = { workspace = true, public = true }
 
 # Public third-party dependencies
+futures-core   = { workspace = true, public = true }
 postgres-types = { workspace = true, public = true, optional = true, features = ["derive", "with-serde_json-1", "with-uuid-1"] }
 specta         = { workspace = true, public = true, optional = true, features = ["derive"] }
 tokio-postgres = { workspace = true, public = true, optional = true }

libs/@local/graph/store/src/lib.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph Store
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 #![feature(
     // Language Features
     impl_trait_in_assoc_type

libs/@local/graph/temporal-versioning/src/lib.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph Temporal Versioning
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 
 mod axis;
 mod bounds;

libs/@local/graph/type-defs/src/lib.rs

@@ -1,7 +1,7 @@
 //! # HASH Graph Type Defs
 //!
 //! ## Workspace dependencies
-#![cfg_attr(doc, doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd"))]
+#![doc = simple_mermaid::mermaid!("../docs/dependency-diagram.mmd")]
 
 pub mod error;
 pub mod status_payloads {