Skip to main content

tidy/
deps.rs

1//! Checks the licenses of third-party dependencies.
2
3use std::collections::{HashMap, HashSet};
4use std::fmt::{Display, Formatter};
5use std::fs::{File, read_dir};
6use std::io::Write;
7use std::path::Path;
8
9use cargo_metadata::semver::Version;
10use cargo_metadata::{Metadata, Package, PackageId};
11
12use crate::diagnostics::{RunningCheck, TidyCtx};
13
14#[path = "../../../bootstrap/src/utils/proc_macro_deps.rs"]
15mod proc_macro_deps;
16
17#[derive(Clone, Copy)]
18struct ListLocation {
19    path: &'static str,
20    line: u32,
21}
22
23impl Display for ListLocation {
24    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
25        write!(f, "{}:{}", self.path, self.line)
26    }
27}
28
29/// Creates a [`ListLocation`] for the current location (with an additional offset to the actual list start);
30macro_rules! location {
31    (+ $offset:literal) => {
32        ListLocation { path: file!(), line: line!() + $offset }
33    };
34}
35
36/// These are licenses that are allowed for all crates, including the runtime,
37/// rustc, tools, etc.
38#[rustfmt::skip]
39const LICENSES: &[&str] = &[
40    // tidy-alphabetical-start
41    "0BSD OR MIT OR Apache-2.0",                           // adler2 license
42    "Apache-2.0 / MIT",
43    "Apache-2.0 OR ISC OR MIT",
44    "Apache-2.0 OR MIT",
45    "Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT", // wasi license
46    "Apache-2.0/MIT",
47    "BSD-2-Clause OR Apache-2.0 OR MIT",                   // zerocopy
48    "BSD-2-Clause OR MIT OR Apache-2.0",
49    "BSD-3-Clause/MIT",
50    "CC0-1.0 OR MIT-0 OR Apache-2.0",
51    "ISC",
52    "MIT / Apache-2.0",
53    "MIT AND (MIT OR Apache-2.0)",
54    "MIT AND Apache-2.0 WITH LLVM-exception AND (MIT OR Apache-2.0)", // compiler-builtins
55    "MIT OR Apache-2.0 OR BSD-1-Clause",
56    "MIT OR Apache-2.0 OR LGPL-2.1-or-later",              // r-efi, r-efi-alloc; LGPL is not acceptable, but we use it under MIT OR Apache-2.0
57    "MIT OR Apache-2.0 OR Zlib",                           // tinyvec_macros
58    "MIT OR Apache-2.0",
59    "MIT OR Zlib OR Apache-2.0",                           // miniz_oxide
60    "MIT",
61    "MIT/Apache-2.0",
62    "Unlicense OR MIT",
63    "Unlicense/MIT",
64    "Zlib",                                                // foldhash (FIXME: see PERMITTED_STDLIB_DEPENDENCIES)
65    // tidy-alphabetical-end
66];
67
68/// These are licenses that are allowed for rustc, tools, etc. But not for the runtime!
69#[rustfmt::skip]
70const LICENSES_TOOLS: &[&str] = &[
71    // tidy-alphabetical-start
72    "(Apache-2.0 OR MIT) AND BSD-3-Clause",
73    "(MIT OR Apache-2.0) AND Unicode-3.0",                 // unicode_ident (1.0.14)
74    "(MIT OR Apache-2.0) AND Unicode-DFS-2016",            // unicode_ident (1.0.12)
75    "0BSD",
76    "Apache-2.0 AND ISC",
77    "Apache-2.0 OR BSL-1.0",  // BSL is not acceptable, but we use it under Apache-2.0
78    "Apache-2.0 OR GPL-2.0-only",
79    "Apache-2.0 WITH LLVM-exception",
80    "Apache-2.0",
81    "BSD-2-Clause",
82    "BSD-3-Clause",
83    "CC0-1.0 OR Apache-2.0 OR Apache-2.0 WITH LLVM-exception",
84    "CC0-1.0",
85    "Unicode-3.0",                                         // icu4x
86    "Unicode-DFS-2016",                                    // tinystr
87    "Zlib OR Apache-2.0 OR MIT",                           // tinyvec
88    "Zlib",
89    // tidy-alphabetical-end
90];
91
92type ExceptionList = &'static [(&'static str, &'static str)];
93
94#[derive(Clone, Copy)]
95pub(crate) struct WorkspaceInfo<'a> {
96    /// Path to the directory containing the workspace root Cargo.toml file.
97    pub(crate) path: &'a str,
98    /// The list of license exceptions.
99    pub(crate) exceptions: ExceptionList,
100    /// Optionally:
101    /// * A list of crates for which dependencies need to be explicitly allowed.
102    /// * The list of allowed dependencies.
103    /// * The source code location of the allowed dependencies list
104    crates_and_deps: Option<(&'a [&'a str], &'a [&'a str], ListLocation)>,
105    /// Submodules required for the workspace
106    pub(crate) submodules: &'a [&'a str],
107}
108
109const WORKSPACE_LOCATION: ListLocation = location!(+4);
110
111/// The workspaces to check for licensing and optionally permitted dependencies.
112// FIXME auto detect all cargo workspaces
113pub(crate) const WORKSPACES: &[WorkspaceInfo<'static>] = &[
114    // The root workspace has to be first for check_rustfix to work.
115    WorkspaceInfo {
116        path: ".",
117        exceptions: EXCEPTIONS,
118        crates_and_deps: Some((
119            &["rustc-main"],
120            PERMITTED_RUSTC_DEPENDENCIES,
121            PERMITTED_RUSTC_DEPS_LOCATION,
122        )),
123        submodules: &[],
124    },
125    WorkspaceInfo {
126        path: "library",
127        exceptions: EXCEPTIONS_STDLIB,
128        crates_and_deps: Some((
129            &["sysroot"],
130            PERMITTED_STDLIB_DEPENDENCIES,
131            PERMITTED_STDLIB_DEPS_LOCATION,
132        )),
133        submodules: &[],
134    },
135    WorkspaceInfo {
136        path: "compiler/rustc_codegen_cranelift",
137        exceptions: EXCEPTIONS_CRANELIFT,
138        crates_and_deps: Some((
139            &["rustc_codegen_cranelift"],
140            PERMITTED_CRANELIFT_DEPENDENCIES,
141            PERMITTED_CRANELIFT_DEPS_LOCATION,
142        )),
143        submodules: &[],
144    },
145    WorkspaceInfo {
146        path: "compiler/rustc_codegen_gcc",
147        exceptions: EXCEPTIONS_GCC,
148        crates_and_deps: None,
149        submodules: &[],
150    },
151    WorkspaceInfo {
152        path: "src/bootstrap",
153        exceptions: EXCEPTIONS_BOOTSTRAP,
154        crates_and_deps: None,
155        submodules: &[],
156    },
157    WorkspaceInfo {
158        path: "src/tools/cargo",
159        exceptions: EXCEPTIONS_CARGO,
160        crates_and_deps: None,
161        submodules: &["src/tools/cargo"],
162    },
163    // FIXME uncomment once all deps are vendored
164    //  WorkspaceInfo {
165    //      path: "src/tools/miri/test-cargo-miri",
166    //      crates_and_deps: None
167    //      submodules: &[],
168    //  },
169    // WorkspaceInfo {
170    //      path: "src/tools/miri/test_dependencies",
171    //      crates_and_deps: None,
172    //      submodules: &[],
173    //  }
174    WorkspaceInfo {
175        path: "src/tools/rust-analyzer",
176        exceptions: EXCEPTIONS_RUST_ANALYZER,
177        crates_and_deps: None,
178        submodules: &[],
179    },
180    WorkspaceInfo {
181        path: "src/tools/rustbook",
182        exceptions: EXCEPTIONS_RUSTBOOK,
183        crates_and_deps: None,
184        submodules: &["src/doc/book", "src/doc/reference"],
185    },
186    WorkspaceInfo {
187        path: "src/tools/rustc-perf",
188        exceptions: EXCEPTIONS_RUSTC_PERF,
189        crates_and_deps: None,
190        submodules: &["src/tools/rustc-perf"],
191    },
192    WorkspaceInfo {
193        path: "tests/run-make-cargo/uefi-qemu/uefi_qemu_test",
194        exceptions: EXCEPTIONS_UEFI_QEMU_TEST,
195        crates_and_deps: None,
196        submodules: &[],
197    },
198];
199
200/// These are exceptions to Rust's permissive licensing policy, and
201/// should be considered bugs. Exceptions are only allowed in Rust
202/// tooling. It is _crucial_ that no exception crates be dependencies
203/// of the Rust runtime (std/test).
204#[rustfmt::skip]
205const EXCEPTIONS: ExceptionList = &[
206    // tidy-alphabetical-start
207    ("colored", "MPL-2.0"),                                  // rustfmt
208    ("option-ext", "MPL-2.0"),                               // cargo-miri (via `directories`)
209    // tidy-alphabetical-end
210];
211
212/// These are exceptions to Rust's permissive licensing policy, and
213/// should be considered bugs. Exceptions are only allowed in Rust
214/// tooling. It is _crucial_ that no exception crates be dependencies
215/// of the Rust runtime (std/test).
216#[rustfmt::skip]
217const EXCEPTIONS_STDLIB: ExceptionList = &[
218    // tidy-alphabetical-start
219    ("fortanix-sgx-abi", "MPL-2.0"), // libstd but only for `sgx` target. FIXME: this dependency violates the documentation comment above.
220    // tidy-alphabetical-end
221];
222
223const EXCEPTIONS_CARGO: ExceptionList = &[
224    // tidy-alphabetical-start
225    ("bitmaps", "MPL-2.0+"),
226    ("im-rc", "MPL-2.0+"),
227    ("sized-chunks", "MPL-2.0+"),
228    // tidy-alphabetical-end
229];
230
231const EXCEPTIONS_RUST_ANALYZER: ExceptionList = &[
232    // tidy-alphabetical-start
233    ("option-ext", "MPL-2.0"),
234    // tidy-alphabetical-end
235];
236
237const EXCEPTIONS_RUSTC_PERF: ExceptionList = &[
238    // tidy-alphabetical-start
239    ("inferno", "CDDL-1.0"),
240    ("option-ext", "MPL-2.0"),
241    // tidy-alphabetical-end
242];
243
244const EXCEPTIONS_RUSTBOOK: ExceptionList = &[
245    // tidy-alphabetical-start
246    ("font-awesome-as-a-crate", "CC-BY-4.0 AND MIT"),
247    ("mdbook-core", "MPL-2.0"),
248    ("mdbook-driver", "MPL-2.0"),
249    ("mdbook-html", "MPL-2.0"),
250    ("mdbook-markdown", "MPL-2.0"),
251    ("mdbook-preprocessor", "MPL-2.0"),
252    ("mdbook-renderer", "MPL-2.0"),
253    ("mdbook-summary", "MPL-2.0"),
254    // tidy-alphabetical-end
255];
256
257const EXCEPTIONS_CRANELIFT: ExceptionList = &[];
258
259const EXCEPTIONS_GCC: ExceptionList = &[
260    // tidy-alphabetical-start
261    ("gccjit", "GPL-3.0"),
262    ("gccjit_sys", "GPL-3.0"),
263    // tidy-alphabetical-end
264];
265
266const EXCEPTIONS_BOOTSTRAP: ExceptionList = &[];
267
268const EXCEPTIONS_UEFI_QEMU_TEST: ExceptionList = &[];
269
270const PERMITTED_RUSTC_DEPS_LOCATION: ListLocation = location!(+6);
271
272/// Crates rustc is allowed to depend on. Avoid adding to the list if possible.
273///
274/// This list is here to provide a speed-bump to adding a new dependency to
275/// rustc. Please check with the compiler team before adding an entry.
276const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
277    // tidy-alphabetical-start
278    "adler2",
279    "aho-corasick",
280    "allocator-api2", // FIXME: only appears in Cargo.lock due to https://github.com/rust-lang/cargo/issues/10801
281    "annotate-snippets",
282    "anstream",
283    "anstyle",
284    "anstyle-parse",
285    "anstyle-query",
286    "anstyle-wincon",
287    "ar_archive_writer",
288    "arrayref",
289    "arrayvec",
290    "bitflags",
291    "blake3",
292    "block-buffer",
293    "block2",
294    "bstr",
295    "cc",
296    "cfg-if",
297    "cfg_aliases",
298    "colorchoice",
299    "constant_time_eq",
300    "cpufeatures",
301    "crc32fast",
302    "crossbeam-deque",
303    "crossbeam-epoch",
304    "crossbeam-utils",
305    "crypto-common",
306    "ctrlc",
307    "darling",
308    "darling_core",
309    "darling_macro",
310    "datafrog",
311    "derive-where",
312    "derive_setters",
313    "digest",
314    "dispatch2",
315    "displaydoc",
316    "dissimilar",
317    "dyn-clone",
318    "either",
319    "elsa",
320    "ena",
321    "equivalent",
322    "errno",
323    "expect-test",
324    "fallible-iterator", // dependency of `thorin`
325    "fastrand",
326    "find-msvc-tools",
327    "flate2",
328    "fluent-bundle",
329    "fluent-langneg",
330    "fluent-syntax",
331    "fnv",
332    "foldhash",
333    "generic-array",
334    "getopts",
335    "getrandom",
336    "gimli",
337    "gsgdt",
338    "hashbrown",
339    "icu_collections",
340    "icu_list",
341    "icu_locale",
342    "icu_locale_core",
343    "icu_locale_data",
344    "icu_provider",
345    "ident_case",
346    "indexmap",
347    "intl-memoizer",
348    "intl_pluralrules",
349    "is_terminal_polyfill",
350    "itertools",
351    "itoa",
352    "jiff",
353    "jiff-static",
354    "jobserver",
355    "lazy_static",
356    "leb128",
357    "libc",
358    "libloading",
359    "linux-raw-sys",
360    "litemap",
361    "lock_api",
362    "log",
363    "matchers",
364    "md-5",
365    "measureme",
366    "memchr",
367    "memmap2",
368    "miniz_oxide",
369    "nix",
370    "nu-ansi-term",
371    "objc2",
372    "objc2-encode",
373    "object",
374    "odht",
375    "once_cell",
376    "once_cell_polyfill",
377    "parking_lot",
378    "parking_lot_core",
379    "pathdiff",
380    "perf-event-open-sys",
381    "pin-project-lite",
382    "polonius-engine",
383    "portable-atomic", // dependency for platforms doesn't support `AtomicU64` in std
384    "portable-atomic-util",
385    "potential_utf",
386    "ppv-lite86",
387    "proc-macro-hack",
388    "proc-macro2",
389    "psm",
390    "pulldown-cmark",
391    "pulldown-cmark-escape",
392    "punycode",
393    "quote",
394    "r-efi",
395    "rand",
396    "rand_chacha",
397    "rand_core",
398    "rand_xorshift", // dependency for doc-tests in rustc_thread_pool
399    "rand_xoshiro",
400    "redox_syscall",
401    "ref-cast",
402    "ref-cast-impl",
403    "regex",
404    "regex-automata",
405    "regex-syntax",
406    "rustc-demangle",
407    "rustc-hash",
408    "rustc-literal-escaper",
409    "rustc-stable-hash",
410    "rustc_apfloat",
411    "rustix",
412    "ruzstd", // via object in thorin-dwp
413    "ryu",
414    "schemars",
415    "schemars_derive",
416    "scoped-tls",
417    "scopeguard",
418    "self_cell",
419    "serde",
420    "serde_core",
421    "serde_derive",
422    "serde_derive_internals",
423    "serde_json",
424    "serde_path_to_error",
425    "sha1",
426    "sha2",
427    "sharded-slab",
428    "shell-words",
429    "shlex",
430    "simd-adler32",
431    "smallvec",
432    "stable_deref_trait",
433    "stacker",
434    "static_assertions",
435    "strsim",
436    "syn",
437    "synstructure",
438    "tempfile",
439    "termize",
440    "thin-vec",
441    "thiserror",
442    "thiserror-impl",
443    "thorin-dwp",
444    "thread_local",
445    "tikv-jemalloc-sys",
446    "tinystr",
447    "tinyvec",
448    "tinyvec_macros",
449    "tracing",
450    "tracing-attributes",
451    "tracing-core",
452    "tracing-log",
453    "tracing-serde",
454    "tracing-subscriber",
455    "tracing-tree",
456    "twox-hash",
457    "type-map",
458    "typenum",
459    "unic-langid",
460    "unic-langid-impl",
461    "unic-langid-macros",
462    "unic-langid-macros-impl",
463    "unicase",
464    "unicode-ident",
465    "unicode-normalization",
466    "unicode-properties",
467    "unicode-script",
468    "unicode-security",
469    "unicode-width",
470    "utf8parse",
471    "valuable",
472    "version_check",
473    "wasi",
474    "wasm-encoder",
475    "wasmparser",
476    "windows",
477    "windows-collections",
478    "windows-core",
479    "windows-future",
480    "windows-implement",
481    "windows-interface",
482    "windows-link",
483    "windows-numerics",
484    "windows-result",
485    "windows-strings",
486    "windows-sys",
487    "windows-targets",
488    "windows-threading",
489    "windows_aarch64_gnullvm",
490    "windows_aarch64_msvc",
491    "windows_i686_gnu",
492    "windows_i686_gnullvm",
493    "windows_i686_msvc",
494    "windows_x86_64_gnu",
495    "windows_x86_64_gnullvm",
496    "windows_x86_64_msvc",
497    "wit-bindgen-rt@0.39.0", // pinned to a specific version due to using a binary blob: <https://github.com/rust-lang/rust/pull/136395#issuecomment-2692769062>
498    "writeable",
499    "yoke",
500    "yoke-derive",
501    "zerocopy",
502    "zerocopy-derive",
503    "zerofrom",
504    "zerofrom-derive",
505    "zerotrie",
506    "zerovec",
507    "zerovec-derive",
508    // tidy-alphabetical-end
509];
510
511const PERMITTED_STDLIB_DEPS_LOCATION: ListLocation = location!(+2);
512
513const PERMITTED_STDLIB_DEPENDENCIES: &[&str] = &[
514    // tidy-alphabetical-start
515    "addr2line",
516    "adler2",
517    "cc",
518    "cfg-if",
519    "compiler_builtins",
520    "dlmalloc",
521    "foldhash", // FIXME: only appears in Cargo.lock due to https://github.com/rust-lang/cargo/issues/10801
522    "fortanix-sgx-abi",
523    "getopts",
524    "gimli",
525    "hashbrown",
526    "hermit-abi",
527    "libc",
528    "memchr",
529    "miniz_oxide",
530    "moto-rt",
531    "object",
532    "r-efi",
533    "r-efi-alloc",
534    "rand",
535    "rand_core",
536    "rand_xorshift",
537    "rustc-demangle",
538    "rustc-literal-escaper",
539    "shlex",
540    "unwinding",
541    "vex-sdk",
542    "wasi",
543    "windows-link",
544    "windows-sys",
545    "windows-targets",
546    "windows_aarch64_gnullvm",
547    "windows_aarch64_msvc",
548    "windows_i686_gnu",
549    "windows_i686_gnullvm",
550    "windows_i686_msvc",
551    "windows_x86_64_gnu",
552    "windows_x86_64_gnullvm",
553    "windows_x86_64_msvc",
554    "wit-bindgen",
555    // tidy-alphabetical-end
556];
557
558const PERMITTED_CRANELIFT_DEPS_LOCATION: ListLocation = location!(+2);
559
560const PERMITTED_CRANELIFT_DEPENDENCIES: &[&str] = &[
561    // tidy-alphabetical-start
562    "allocator-api2",
563    "anyhow",
564    "arbitrary",
565    "bitflags",
566    "bumpalo",
567    "cfg-if",
568    "cranelift-assembler-x64",
569    "cranelift-assembler-x64-meta",
570    "cranelift-bforest",
571    "cranelift-bitset",
572    "cranelift-codegen",
573    "cranelift-codegen-meta",
574    "cranelift-codegen-shared",
575    "cranelift-control",
576    "cranelift-entity",
577    "cranelift-frontend",
578    "cranelift-isle",
579    "cranelift-jit",
580    "cranelift-module",
581    "cranelift-native",
582    "cranelift-object",
583    "cranelift-srcgen",
584    "crc32fast",
585    "equivalent",
586    "fallible-iterator",
587    "foldhash",
588    "gimli",
589    "hashbrown",
590    "heck",
591    "indexmap",
592    "libc",
593    "libloading",
594    "libm",
595    "log",
596    "mach2",
597    "memchr",
598    "object",
599    "proc-macro2",
600    "quote",
601    "regalloc2",
602    "region",
603    "rustc-hash",
604    "serde",
605    "serde_core",
606    "serde_derive",
607    "smallvec",
608    "stable_deref_trait",
609    "syn",
610    "target-lexicon",
611    "unicode-ident",
612    "wasmtime-internal-jit-icache-coherence",
613    "wasmtime-internal-math",
614    "windows-link",
615    "windows-sys",
616    "windows-targets",
617    "windows_aarch64_gnullvm",
618    "windows_aarch64_msvc",
619    "windows_i686_gnu",
620    "windows_i686_gnullvm",
621    "windows_i686_msvc",
622    "windows_x86_64_gnu",
623    "windows_x86_64_gnullvm",
624    "windows_x86_64_msvc",
625    // tidy-alphabetical-end
626];
627
628/// Dependency checks.
629///
630/// `root` is path to the directory with the root `Cargo.toml` (for the workspace). `cargo` is path
631/// to the cargo executable.
632pub fn check(root: &Path, cargo: &Path, tidy_ctx: TidyCtx) {
633    let mut check = tidy_ctx.start_check("deps");
634    let bless = tidy_ctx.is_bless_enabled();
635
636    let mut checked_runtime_licenses = false;
637
638    check_proc_macro_dep_list(root, cargo, bless, &mut check);
639
640    for &WorkspaceInfo { path, exceptions, crates_and_deps, submodules } in WORKSPACES {
641        if has_missing_submodule(root, submodules, tidy_ctx.is_running_on_ci()) {
642            continue;
643        }
644
645        if !root.join(path).join("Cargo.lock").exists() {
646            check.error(format!("the `{path}` workspace doesn't have a Cargo.lock"));
647            continue;
648        }
649
650        let mut cmd = cargo_metadata::MetadataCommand::new();
651        cmd.cargo_path(cargo)
652            .manifest_path(root.join(path).join("Cargo.toml"))
653            .features(cargo_metadata::CargoOpt::AllFeatures)
654            .other_options(vec!["--locked".to_owned()]);
655        let metadata = t!(cmd.exec());
656
657        // Check for packages which have been moved into a different workspace and not updated
658        let absolute_root =
659            if path == "." { root.to_path_buf() } else { t!(std::path::absolute(root.join(path))) };
660        let absolute_root_real = t!(std::path::absolute(&metadata.workspace_root));
661        if absolute_root_real != absolute_root {
662            check.error(format!("{path} is part of another workspace ({} != {}), remove from `WORKSPACES` ({WORKSPACE_LOCATION})", absolute_root.display(), absolute_root_real.display()));
663        }
664        check_license_exceptions(&metadata, path, exceptions, &mut check);
665        if let Some((crates, permitted_deps, location)) = crates_and_deps {
666            let descr = crates.get(0).unwrap_or(&path);
667            check_permitted_dependencies(
668                &metadata,
669                descr,
670                permitted_deps,
671                crates,
672                location,
673                &mut check,
674            );
675        }
676
677        if path == "library" {
678            check_runtime_license_exceptions(&metadata, &mut check);
679            check_runtime_no_duplicate_dependencies(&metadata, &mut check);
680            check_runtime_no_proc_macros(&metadata, &mut check);
681            checked_runtime_licenses = true;
682        }
683    }
684
685    // Sanity check to ensure we don't accidentally remove the workspace containing the runtime
686    // crates.
687    assert!(checked_runtime_licenses);
688}
689
690/// Ensure the list of proc-macro crate transitive dependencies is up to date
691fn check_proc_macro_dep_list(root: &Path, cargo: &Path, bless: bool, check: &mut RunningCheck) {
692    let mut cmd = cargo_metadata::MetadataCommand::new();
693    cmd.cargo_path(cargo)
694        .manifest_path(root.join("Cargo.toml"))
695        .features(cargo_metadata::CargoOpt::AllFeatures)
696        .other_options(vec!["--locked".to_owned()]);
697    let metadata = t!(cmd.exec());
698    let is_proc_macro_pkg = |pkg: &Package| pkg.targets.iter().any(|target| target.is_proc_macro());
699
700    let mut proc_macro_deps = HashSet::new();
701    for pkg in metadata.packages.iter().filter(|pkg| is_proc_macro_pkg(pkg)) {
702        deps_of(&metadata, &pkg.id, &mut proc_macro_deps);
703    }
704    // Remove the proc-macro crates themselves
705    proc_macro_deps.retain(|pkg| !is_proc_macro_pkg(&metadata[pkg]));
706
707    let proc_macro_deps: HashSet<_> =
708        proc_macro_deps.into_iter().map(|dep| metadata[dep].name.as_ref()).collect();
709    let expected = proc_macro_deps::CRATES.iter().copied().collect::<HashSet<_>>();
710
711    let needs_blessing = proc_macro_deps.difference(&expected).next().is_some()
712        || expected.difference(&proc_macro_deps).next().is_some();
713
714    if needs_blessing && bless {
715        let mut proc_macro_deps: Vec<_> = proc_macro_deps.into_iter().collect();
716        proc_macro_deps.sort();
717        let mut file = File::create(root.join("src/bootstrap/src/utils/proc_macro_deps.rs"))
718            .expect("`proc_macro_deps` should exist");
719        writeln!(
720            &mut file,
721            "/// Do not update manually - use `./x.py test tidy --bless`
722/// Holds all direct and indirect dependencies of proc-macro crates in tree.
723/// See <https://github.com/rust-lang/rust/issues/134863>
724pub static CRATES: &[&str] = &[
725    // tidy-alphabetical-start"
726        )
727        .unwrap();
728        for dep in proc_macro_deps {
729            writeln!(&mut file, "    {dep:?},").unwrap();
730        }
731        writeln!(
732            &mut file,
733            "    // tidy-alphabetical-end
734];"
735        )
736        .unwrap();
737    } else {
738        let mut error_found = false;
739
740        for missing in proc_macro_deps.difference(&expected) {
741            error_found = true;
742            check.error(format!(
743                "proc-macro crate dependency `{missing}` is not registered in `src/bootstrap/src/utils/proc_macro_deps.rs`",
744            ));
745        }
746        for extra in expected.difference(&proc_macro_deps) {
747            error_found = true;
748            check.error(format!(
749                "`{extra}` is registered in `src/bootstrap/src/utils/proc_macro_deps.rs`, but is not a proc-macro crate dependency",
750            ));
751        }
752        if error_found {
753            check.message("Run `./x.py test tidy --bless` to regenerate the list");
754        }
755    }
756}
757
758/// Used to skip a check if a submodule is not checked out, and not in a CI environment.
759///
760/// This helps prevent enforcing developers to fetch submodules for tidy.
761pub fn has_missing_submodule(root: &Path, submodules: &[&str], is_ci: bool) -> bool {
762    !is_ci
763        && submodules.iter().any(|submodule| {
764            let path = root.join(submodule);
765            !path.exists()
766            // If the directory is empty, we can consider it as an uninitialized submodule.
767            || read_dir(path).unwrap().next().is_none()
768        })
769}
770
771/// Check that all licenses of runtime dependencies are in the valid list in `LICENSES`.
772///
773/// Unlike for tools we don't allow exceptions to the `LICENSES` list for the runtime with the sole
774/// exception of `fortanix-sgx-abi` which is only used on x86_64-fortanix-unknown-sgx.
775fn check_runtime_license_exceptions(metadata: &Metadata, check: &mut RunningCheck) {
776    for pkg in &metadata.packages {
777        if pkg.source.is_none() {
778            // No need to check local packages.
779            continue;
780        }
781        let license = match &pkg.license {
782            Some(license) => license,
783            None => {
784                check
785                    .error(format!("dependency `{}` does not define a license expression", pkg.id));
786                continue;
787            }
788        };
789        if !LICENSES.contains(&license.as_str()) {
790            // This is a specific exception because SGX is considered "third party".
791            // See https://github.com/rust-lang/rust/issues/62620 for more.
792            // In general, these should never be added and this exception
793            // should not be taken as precedent for any new target.
794            if *pkg.name == "fortanix-sgx-abi" && pkg.license.as_deref() == Some("MPL-2.0") {
795                continue;
796            }
797
798            check.error(format!("invalid license `{}` in `{}`", license, pkg.id));
799        }
800    }
801}
802
803/// Check that all licenses of tool dependencies are in the valid list in `LICENSES`.
804///
805/// Packages listed in `exceptions` are allowed for tools.
806fn check_license_exceptions(
807    metadata: &Metadata,
808    workspace: &str,
809    exceptions: &[(&str, &str)],
810    check: &mut RunningCheck,
811) {
812    // Validate the EXCEPTIONS list hasn't changed.
813    for (name, license) in exceptions {
814        // Check that the package actually exists.
815        if !metadata.packages.iter().any(|p| *p.name == *name) {
816            check.error(format!(
817                "could not find exception package `{name}` in workspace `{workspace}`\n\
818                Remove from EXCEPTIONS list if it is no longer used.",
819            ));
820        }
821        // Check that the license hasn't changed.
822        for pkg in metadata.packages.iter().filter(|p| *p.name == *name) {
823            match &pkg.license {
824                None => {
825                    check.error(format!(
826                        "dependency exception `{}` in workspace `{workspace}` does not declare a license expression",
827                        pkg.id
828                    ));
829                }
830                Some(pkg_license) => {
831                    if pkg_license.as_str() != *license {
832                        check.error(format!(r#"dependency exception `{name}` license in workspace `{workspace}` has changed
833    previously `{license}` now `{pkg_license}`
834    update EXCEPTIONS for the new license
835"#));
836                    }
837                }
838            }
839        }
840        if LICENSES.contains(license) || LICENSES_TOOLS.contains(license) {
841            check.error(format!(
842                "dependency exception `{name}` is not necessary. `{license}` is an allowed license"
843            ));
844        }
845    }
846
847    let exception_names: Vec<_> = exceptions.iter().map(|(name, _license)| *name).collect();
848
849    // Check if any package does not have a valid license.
850    for pkg in &metadata.packages {
851        if pkg.source.is_none() {
852            // No need to check local packages.
853            continue;
854        }
855        if exception_names.contains(&pkg.name.as_str()) {
856            continue;
857        }
858        let license = match &pkg.license {
859            Some(license) => license,
860            None => {
861                check.error(format!(
862                    "dependency `{}` in workspace `{workspace}` does not define a license expression",
863                    pkg.id
864                ));
865                continue;
866            }
867        };
868        if !LICENSES.contains(&license.as_str()) && !LICENSES_TOOLS.contains(&license.as_str()) {
869            check.error(format!(
870                "invalid license `{}` for package `{}` in workspace `{workspace}`",
871                license, pkg.id
872            ));
873        }
874    }
875}
876
877fn check_runtime_no_duplicate_dependencies(metadata: &Metadata, check: &mut RunningCheck) {
878    let mut seen_pkgs = HashSet::new();
879    for pkg in &metadata.packages {
880        if pkg.source.is_none() {
881            continue;
882        }
883
884        // Skip the `wasi` crate here which the standard library explicitly
885        // depends on two version of (one for the `wasm32-wasip1` target and
886        // another for the `wasm32-wasip2` target).
887        if pkg.name.to_string() != "wasi" && !seen_pkgs.insert(&*pkg.name) {
888            check.error(format!(
889                "duplicate package `{}` is not allowed for the standard library",
890                pkg.name
891            ));
892        }
893    }
894}
895
896fn check_runtime_no_proc_macros(metadata: &Metadata, check: &mut RunningCheck) {
897    for pkg in &metadata.packages {
898        if pkg.targets.iter().any(|target| target.is_proc_macro()) {
899            check.error(format!(
900                "proc macro `{}` is not allowed as standard library dependency.\n\
901                Using proc macros in the standard library would break cross-compilation \
902                as proc-macros don't get shipped for the host tuple.",
903                pkg.name
904            ));
905        }
906    }
907}
908
909/// Checks the dependency of `restricted_dependency_crates` at the given path. Changes `bad` to
910/// `true` if a check failed.
911///
912/// Specifically, this checks that the dependencies are on the `permitted_dependencies`.
913fn check_permitted_dependencies(
914    metadata: &Metadata,
915    descr: &str,
916    permitted_dependencies: &[&'static str],
917    restricted_dependency_crates: &[&'static str],
918    permitted_location: ListLocation,
919    check: &mut RunningCheck,
920) {
921    let mut has_permitted_dep_error = false;
922    let mut deps = HashSet::new();
923    for to_check in restricted_dependency_crates {
924        let to_check = pkg_from_name(metadata, to_check);
925        deps_of(metadata, &to_check.id, &mut deps);
926    }
927
928    // Check that the PERMITTED_DEPENDENCIES does not have unused entries.
929    for permitted in permitted_dependencies {
930        fn compare(pkg: &Package, permitted: &str) -> bool {
931            if let Some((name, version)) = permitted.split_once("@") {
932                let Ok(version) = Version::parse(version) else {
933                    return false;
934                };
935                *pkg.name == name && pkg.version == version
936            } else {
937                *pkg.name == permitted
938            }
939        }
940        if !deps.iter().any(|dep_id| compare(pkg_from_id(metadata, dep_id), permitted)) {
941            check.error(format!(
942                "could not find allowed package `{permitted}`\n\
943                Remove from PERMITTED_DEPENDENCIES list if it is no longer used.",
944            ));
945            has_permitted_dep_error = true;
946        }
947    }
948
949    // Get in a convenient form.
950    let permitted_dependencies: HashMap<_, _> = permitted_dependencies
951        .iter()
952        .map(|s| {
953            if let Some((name, version)) = s.split_once('@') {
954                (name, Version::parse(version).ok())
955            } else {
956                (*s, None)
957            }
958        })
959        .collect();
960
961    for dep in deps {
962        let dep = pkg_from_id(metadata, dep);
963        // If this path is in-tree, we don't require it to be explicitly permitted.
964        if dep.source.is_some() {
965            let is_eq = if let Some(version) = permitted_dependencies.get(dep.name.as_str()) {
966                if let Some(version) = version { version == &dep.version } else { true }
967            } else {
968                false
969            };
970            if !is_eq {
971                check.error(format!("Dependency for {descr} not explicitly permitted: {}", dep.id));
972                has_permitted_dep_error = true;
973            }
974        }
975    }
976
977    if has_permitted_dep_error {
978        eprintln!("Go to `{}:{}` for the list.", permitted_location.path, permitted_location.line);
979    }
980}
981
982/// Finds a package with the given name.
983fn pkg_from_name<'a>(metadata: &'a Metadata, name: &'static str) -> &'a Package {
984    let mut i = metadata.packages.iter().filter(|p| *p.name == name);
985    let result =
986        i.next().unwrap_or_else(|| panic!("could not find package `{name}` in package list"));
987    assert!(i.next().is_none(), "more than one package found for `{name}`");
988    result
989}
990
991fn pkg_from_id<'a>(metadata: &'a Metadata, id: &PackageId) -> &'a Package {
992    metadata.packages.iter().find(|p| &p.id == id).unwrap()
993}
994
995/// Recursively find all dependencies.
996fn deps_of<'a>(metadata: &'a Metadata, pkg_id: &'a PackageId, result: &mut HashSet<&'a PackageId>) {
997    if !result.insert(pkg_id) {
998        return;
999    }
1000    let node = metadata
1001        .resolve
1002        .as_ref()
1003        .unwrap()
1004        .nodes
1005        .iter()
1006        .find(|n| &n.id == pkg_id)
1007        .unwrap_or_else(|| panic!("could not find `{pkg_id}` in resolve"));
1008    for dep in &node.deps {
1009        deps_of(metadata, &dep.pkg, result);
1010    }
1011}