Move rustc_middle::middle::stability to rustc_crate.

Author: cjgillot

compiler/rustc_crate/src/lib.rs

@@ -15,6 +15,7 @@ pub mod cstore;
 pub mod dependency_format;
 pub mod limits;
 pub mod privacy;
+pub mod stability;
 
 #[derive(HashStable_Generic)]
 pub struct LibFeatures {

compiler/rustc_crate/src/stability.rs

@@ -0,0 +1,217 @@
+//! A pass that annotates every item and method with its stability level,
+//! propagating default levels lexically from parent to children ast nodes.
+
+pub use self::StabilityLevel::*;
+
+use rustc_ast::CRATE_NODE_ID;
+use rustc_attr::{self as attr, ConstStability, Deprecation, Stability};
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_errors::{Applicability, DiagnosticBuilder};
+use rustc_feature::GateIssue;
+use rustc_hir::def_id::CrateNum;
+use rustc_hir::{self, HirId};
+use rustc_session::lint::builtin::{DEPRECATED, DEPRECATED_IN_FUTURE, SOFT_UNSTABLE};
+use rustc_session::lint::{BuiltinLintDiagnostics, Lint, LintBuffer};
+use rustc_session::parse::feature_err_issue;
+use rustc_session::{DiagnosticMessageId, Session};
+use rustc_span::symbol::Symbol;
+use rustc_span::{MultiSpan, Span};
+
+use std::num::NonZeroU32;
+
+#[derive(PartialEq, Clone, Copy, Debug)]
+pub enum StabilityLevel {
+    Unstable,
+    Stable,
+}
+
+impl StabilityLevel {
+    pub fn from_attr_level(level: &attr::StabilityLevel) -> Self {
+        if level.is_stable() { Stable } else { Unstable }
+    }
+}
+
+/// An entry in the `depr_map`.
+#[derive(Clone, HashStable_Generic)]
+pub struct DeprecationEntry {
+    /// The metadata of the attribute associated with this entry.
+    pub attr: Deprecation,
+    /// The `DefId` where the attr was originally attached. `None` for non-local
+    /// `DefId`'s.
+    origin: Option<HirId>,
+}
+
+impl DeprecationEntry {
+    pub fn local(attr: Deprecation, id: HirId) -> DeprecationEntry {
+        DeprecationEntry { attr, origin: Some(id) }
+    }
+
+    pub fn external(attr: Deprecation) -> DeprecationEntry {
+        DeprecationEntry { attr, origin: None }
+    }
+
+    pub fn same_origin(&self, other: &DeprecationEntry) -> bool {
+        match (self.origin, other.origin) {
+            (Some(o1), Some(o2)) => o1 == o2,
+            _ => false,
+        }
+    }
+}
+
+/// A stability index, giving the stability level for items and methods.
+#[derive(HashStable_Generic)]
+pub struct Index<'tcx> {
+    /// This is mostly a cache, except the stabilities of local items
+    /// are filled by the annotator.
+    pub stab_map: FxHashMap<HirId, &'tcx Stability>,
+    pub const_stab_map: FxHashMap<HirId, &'tcx ConstStability>,
+    pub depr_map: FxHashMap<HirId, DeprecationEntry>,
+
+    /// Maps for each crate whether it is part of the staged API.
+    pub staged_api: FxHashMap<CrateNum, bool>,
+
+    /// Features enabled for this crate.
+    pub active_features: FxHashSet<Symbol>,
+}
+
+impl<'tcx> Index<'tcx> {
+    pub fn local_stability(&self, id: HirId) -> Option<&'tcx Stability> {
+        self.stab_map.get(&id).cloned()
+    }
+
+    pub fn local_const_stability(&self, id: HirId) -> Option<&'tcx ConstStability> {
+        self.const_stab_map.get(&id).cloned()
+    }
+
+    pub fn local_deprecation_entry(&self, id: HirId) -> Option<DeprecationEntry> {
+        self.depr_map.get(&id).cloned()
+    }
+}
+
+pub fn report_unstable(
+    sess: &Session,
+    feature: Symbol,
+    reason: Option<Symbol>,
+    issue: Option<NonZeroU32>,
+    is_soft: bool,
+    span: Span,
+    soft_handler: impl FnOnce(&'static Lint, Span, &str),
+) {
+    let msg = match reason {
+        Some(r) => format!("use of unstable library feature '{}': {}", feature, r),
+        None => format!("use of unstable library feature '{}'", &feature),
+    };
+
+    let msp: MultiSpan = span.into();
+    let sm = &sess.parse_sess.source_map();
+    let span_key = msp.primary_span().and_then(|sp: Span| {
+        if !sp.is_dummy() {
+            let file = sm.lookup_char_pos(sp.lo()).file;
+            if file.is_imported() { None } else { Some(span) }
+        } else {
+            None
+        }
+    });
+
+    let error_id = (DiagnosticMessageId::StabilityId(issue), span_key, msg.clone());
+    let fresh = sess.one_time_diagnostics.borrow_mut().insert(error_id);
+    if fresh {
+        if is_soft {
+            soft_handler(SOFT_UNSTABLE, span, &msg)
+        } else {
+            feature_err_issue(&sess.parse_sess, feature, span, GateIssue::Library(issue), &msg)
+                .emit();
+        }
+    }
+}
+
+/// Checks whether an item marked with `deprecated(since="X")` is currently
+/// deprecated (i.e., whether X is not greater than the current rustc version).
+pub fn deprecation_in_effect(is_since_rustc_version: bool, since: Option<&str>) -> bool {
+    let since = if let Some(since) = since {
+        if is_since_rustc_version {
+            since
+        } else {
+            // We assume that the deprecation is in effect if it's not a
+            // rustc version.
+            return true;
+        }
+    } else {
+        // If since attribute is not set, then we're definitely in effect.
+        return true;
+    };
+    fn parse_version(ver: &str) -> Vec<u32> {
+        // We ignore non-integer components of the version (e.g., "nightly").
+        ver.split(|c| c == '.' || c == '-').flat_map(|s| s.parse()).collect()
+    }
+
+    if let Some(rustc) = option_env!("CFG_RELEASE") {
+        let since: Vec<u32> = parse_version(&since);
+        let rustc: Vec<u32> = parse_version(rustc);
+        // We simply treat invalid `since` attributes as relating to a previous
+        // Rust version, thus always displaying the warning.
+        if since.len() != 3 {
+            return true;
+        }
+        since <= rustc
+    } else {
+        // By default, a deprecation warning applies to
+        // the current version of the compiler.
+        true
+    }
+}
+
+pub fn deprecation_suggestion(
+    diag: &mut DiagnosticBuilder<'_>,
+    kind: &str,
+    suggestion: Option<Symbol>,
+    span: Span,
+) {
+    if let Some(suggestion) = suggestion {
+        diag.span_suggestion(
+            span,
+            &format!("replace the use of the deprecated {}", kind),
+            suggestion.to_string(),
+            Applicability::MachineApplicable,
+        );
+    }
+}
+
+pub fn deprecation_message(depr: &Deprecation, kind: &str, path: &str) -> (String, &'static Lint) {
+    let (message, lint) = if deprecation_in_effect(
+        depr.is_since_rustc_version,
+        depr.since.map(Symbol::as_str).as_deref(),
+    ) {
+        (format!("use of deprecated {} `{}`", kind, path), DEPRECATED)
+    } else {
+        (
+            format!(
+                "use of {} `{}` that will be deprecated in future version {}",
+                kind,
+                path,
+                depr.since.unwrap()
+            ),
+            DEPRECATED_IN_FUTURE,
+        )
+    };
+    let message = match depr.note {
+        Some(reason) => format!("{}: {}", message, reason),
+        None => message,
+    };
+    (message, lint)
+}
+
+pub fn early_report_deprecation<'a>(
+    lint_buffer: &'a mut LintBuffer,
+    message: &str,
+    suggestion: Option<Symbol>,
+    lint: &'static Lint,
+    span: Span,
+) {
+    if span.in_derive_expansion() {
+        return;
+    }
+
+    let diag = BuiltinLintDiagnostics::DeprecatedMacro(suggestion, span);
+    lint_buffer.buffer_lint_with_diagnostic(lint, CRATE_NODE_ID, span, message, diag);
+}

compiler/rustc_lint/src/context.rs

@@ -21,6 +21,7 @@ use crate::passes::{EarlyLintPassObject, LateLintPassObject};
 use rustc_ast as ast;
 use rustc_ast::util::lev_distance::find_best_match_for_name;
 use rustc_crate::privacy::AccessLevels;
+use rustc_crate::stability;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync;
 use rustc_errors::{add_elided_lifetime_in_path_suggestion, struct_span_err, Applicability};
@@ -29,7 +30,6 @@ use rustc_hir::def::Res;
 use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
 use rustc_middle::lint::LintDiagnosticBuilder;
-use rustc_middle::middle::stability;
 use rustc_middle::ty::layout::{LayoutError, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, print::Printer, subst::GenericArg, Ty, TyCtxt};

compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs

@@ -7,6 +7,7 @@ use crate::rmeta;
 use rustc_ast as ast;
 use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_crate::cstore::{CrateSource, CrateStore, ForeignModule};
+use rustc_crate::stability::DeprecationEntry;
 use rustc_data_structures::stable_map::FxHashMap;
 use rustc_data_structures::svh::Svh;
 use rustc_hir as hir;
@@ -15,7 +16,6 @@ use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, CRATE_DEF_INDEX, LOCAL_CRATE}
 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash};
 use rustc_middle::hir::exports::Export;
 use rustc_middle::middle::exported_symbols::ExportedSymbol;
-use rustc_middle::middle::stability::DeprecationEntry;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::utils::NativeLibKind;