gating diagnostics -> rustc_session::parse

Cargo.lock

@@ -3866,6 +3866,7 @@ dependencies = [
  "log",
  "num_cpus",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_feature",
  "rustc_fs_util",

src/librustc_session/Cargo.toml

@@ -10,6 +10,7 @@ path = "lib.rs"
 
 [dependencies]
 log = "0.4"
+rustc_error_codes = { path = "../librustc_error_codes" }
 rustc_errors = { path = "../librustc_errors" }
 rustc_feature = { path = "../librustc_feature" }
 rustc_target = { path = "../librustc_target" }

src/librustc_session/parse.rs

@@ -6,10 +6,10 @@ use crate::node_id::NodeId;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::{Lock, Lrc, Once};
-use rustc_errors::{
-    emitter::SilentEmitter, Applicability, ColorConfig, DiagnosticBuilder, Handler,
-};
-use rustc_feature::UnstableFeatures;
+use rustc_error_codes::E0658;
+use rustc_errors::{emitter::SilentEmitter, ColorConfig, Handler};
+use rustc_errors::{error_code, Applicability, DiagnosticBuilder};
+use rustc_feature::{find_feature_issue, GateIssue, UnstableFeatures};
 use rustc_span::edition::Edition;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::source_map::{FilePathMapping, SourceMap};
@@ -62,6 +62,70 @@ impl GatedSpans {
     }
 }
 
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub enum GateStrength {
+    /// A hard error. (Most feature gates should use this.)
+    Hard,
+    /// Only a warning. (Use this only as backwards-compatibility demands.)
+    Soft,
+}
+
+pub fn feature_err<'a>(
+    sess: &'a ParseSess,
+    feature: Symbol,
+    span: impl Into<MultiSpan>,
+    explain: &str,
+) -> DiagnosticBuilder<'a> {
+    feature_err_issue(sess, feature, span, GateIssue::Language, explain)
+}
+
+pub fn feature_err_issue<'a>(
+    sess: &'a ParseSess,
+    feature: Symbol,
+    span: impl Into<MultiSpan>,
+    issue: GateIssue,
+    explain: &str,
+) -> DiagnosticBuilder<'a> {
+    leveled_feature_err(sess, feature, span, issue, explain, GateStrength::Hard)
+}
+
+pub fn leveled_feature_err<'a>(
+    sess: &'a ParseSess,
+    feature: Symbol,
+    span: impl Into<MultiSpan>,
+    issue: GateIssue,
+    explain: &str,
+    level: GateStrength,
+) -> DiagnosticBuilder<'a> {
+    let diag = &sess.span_diagnostic;
+
+    let mut err = match level {
+        GateStrength::Hard => diag.struct_span_err_with_code(span, explain, error_code!(E0658)),
+        GateStrength::Soft => diag.struct_span_warn(span, explain),
+    };
+
+    if let Some(n) = find_feature_issue(feature, issue) {
+        err.note(&format!(
+            "for more information, see https://github.com/rust-lang/rust/issues/{}",
+            n,
+        ));
+    }
+
+    // #23973: do not suggest `#![feature(...)]` if we are in beta/stable
+    if sess.unstable_features.is_nightly_build() {
+        err.help(&format!("add `#![feature({})]` to the crate attributes to enable", feature));
+    }
+
+    // If we're on stable and only emitting a "soft" warning, add a note to
+    // clarify that the feature isn't "on" (rather than being on but
+    // warning-worthy).
+    if !sess.unstable_features.is_nightly_build() && level == GateStrength::Soft {
+        err.help("a nightly build of the compiler is required to enable this feature");
+    }
+
+    err
+}
+
 /// Info about a parsing session.
 pub struct ParseSess {
     pub span_diagnostic: Handler,

src/libsyntax/attr/builtin.rs

@@ -2,9 +2,8 @@
 
 use super::{mark_used, MetaItemKind};
 use crate::ast::{self, Attribute, MetaItem, NestedMetaItem};
-use crate::feature_gate::feature_err;
 use crate::print::pprust;
-use crate::sess::ParseSess;
+use crate::sess::{feature_err, ParseSess};
 
 use rustc_errors::{struct_span_err, Applicability, Handler};
 use rustc_feature::{find_gated_cfg, is_builtin_attr_name, Features, GatedCfg};

src/libsyntax/feature_gate/check.rs

@@ -1,22 +1,21 @@
 use crate::ast::{self, AssocTyConstraint, AssocTyConstraintKind, NodeId};
 use crate::ast::{GenericParam, GenericParamKind, PatKind, RangeEnd, VariantData};
 use crate::attr;
-use crate::sess::ParseSess;
+use crate::sess::{feature_err, leveled_feature_err, GateStrength, ParseSess};
 use crate::visit::{self, FnKind, Visitor};
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_error_codes::*;
-use rustc_errors::{error_code, struct_span_err, Applicability, DiagnosticBuilder, Handler};
-use rustc_feature::{find_feature_issue, GateIssue};
+use rustc_errors::{error_code, struct_span_err, Applicability, Handler};
 use rustc_feature::{AttributeGate, BUILTIN_ATTRIBUTE_MAP};
-use rustc_feature::{Feature, Features, State as FeatureState, UnstableFeatures};
+use rustc_feature::{Feature, Features, GateIssue, State as FeatureState, UnstableFeatures};
 use rustc_feature::{
     ACCEPTED_FEATURES, ACTIVE_FEATURES, REMOVED_FEATURES, STABLE_REMOVED_FEATURES,
 };
 use rustc_span::edition::{Edition, ALL_EDITIONS};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{sym, Symbol};
-use rustc_span::{MultiSpan, Span, DUMMY_SP};
+use rustc_span::{Span, DUMMY_SP};
 
 use log::debug;
 
@@ -53,70 +52,6 @@ pub fn check_attribute(attr: &ast::Attribute, parse_sess: &ParseSess, features:
     PostExpansionVisitor { parse_sess, features }.visit_attribute(attr)
 }
 
-#[derive(Debug, Copy, Clone, PartialEq)]
-pub enum GateStrength {
-    /// A hard error. (Most feature gates should use this.)
-    Hard,
-    /// Only a warning. (Use this only as backwards-compatibility demands.)
-    Soft,
-}
-
-pub fn feature_err<'a>(
-    sess: &'a ParseSess,
-    feature: Symbol,
-    span: impl Into<MultiSpan>,
-    explain: &str,
-) -> DiagnosticBuilder<'a> {
-    feature_err_issue(sess, feature, span, GateIssue::Language, explain)
-}
-
-pub fn feature_err_issue<'a>(
-    sess: &'a ParseSess,
-    feature: Symbol,
-    span: impl Into<MultiSpan>,
-    issue: GateIssue,
-    explain: &str,
-) -> DiagnosticBuilder<'a> {
-    leveled_feature_err(sess, feature, span, issue, explain, GateStrength::Hard)
-}
-
-fn leveled_feature_err<'a>(
-    sess: &'a ParseSess,
-    feature: Symbol,
-    span: impl Into<MultiSpan>,
-    issue: GateIssue,
-    explain: &str,
-    level: GateStrength,
-) -> DiagnosticBuilder<'a> {
-    let diag = &sess.span_diagnostic;
-
-    let mut err = match level {
-        GateStrength::Hard => diag.struct_span_err_with_code(span, explain, error_code!(E0658)),
-        GateStrength::Soft => diag.struct_span_warn(span, explain),
-    };
-
-    if let Some(n) = find_feature_issue(feature, issue) {
-        err.note(&format!(
-            "for more information, see https://github.com/rust-lang/rust/issues/{}",
-            n,
-        ));
-    }
-
-    // #23973: do not suggest `#![feature(...)]` if we are in beta/stable
-    if sess.unstable_features.is_nightly_build() {
-        err.help(&format!("add `#![feature({})]` to the crate attributes to enable", feature));
-    }
-
-    // If we're on stable and only emitting a "soft" warning, add a note to
-    // clarify that the feature isn't "on" (rather than being on but
-    // warning-worthy).
-    if !sess.unstable_features.is_nightly_build() && level == GateStrength::Soft {
-        err.help("a nightly build of the compiler is required to enable this feature");
-    }
-
-    err
-}
-
 struct PostExpansionVisitor<'a> {
     parse_sess: &'a ParseSess,
     features: &'a Features,

src/libsyntax/lib.rs

@@ -77,7 +77,8 @@ pub mod entry;
 pub mod expand;
 pub mod feature_gate {
     mod check;
-    pub use check::{check_attribute, check_crate, feature_err, feature_err_issue, get_features};
+    pub use check::{check_attribute, check_crate, get_features};
+    pub use rustc_session::parse::{feature_err, feature_err_issue};
 }
 pub mod mut_visit;
 pub mod ptr;