From 22465b35a608487773f960574a798262b23c4abd Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Thu, 8 Oct 2020 18:20:00 +0200
Subject: [PATCH] Apply same treatment to MISSING_DOC_CODE_EXAMPLES

---
 .../passes/calculate_doc_coverage.rs          |  5 +++--
 src/librustdoc/passes/doc_test_lints.rs       | 15 ++++++++++----
 .../coverage/allow_missing_docs.stderr        | 20 +++++++++++++++++++
 3 files changed, 34 insertions(+), 6 deletions(-)
 create mode 100644 src/test/rustdoc-ui/coverage/allow_missing_docs.stderr

diff --git a/src/librustdoc/passes/calculate_doc_coverage.rs b/src/librustdoc/passes/calculate_doc_coverage.rs
index 093b77d4e94..7cdd9a590ba 100644
--- a/src/librustdoc/passes/calculate_doc_coverage.rs
+++ b/src/librustdoc/passes/calculate_doc_coverage.rs
@@ -254,12 +254,13 @@ impl<'a, 'b> fold::DocFolder for CoverageCalculator<'a, 'b> {
                 let has_doc_example = tests.found_tests != 0;
                 let hir_id = self.ctx.tcx.hir().local_def_id_to_hir_id(i.def_id.expect_local());
                 let (level, source) = self.ctx.tcx.lint_level_at_node(MISSING_DOCS, hir_id);
-                let should_have_docs = level != lint::Level::Allow || !matches!(source, LintSource::Node(..));
+                let should_have_docs =
+                    level != lint::Level::Allow || !matches!(source, LintSource::Node(..));
                 debug!("counting {:?} {:?} in {}", i.type_(), i.name, i.source.filename);
                 self.items.entry(i.source.filename.clone()).or_default().count_item(
                     has_docs,
                     has_doc_example,
-                    should_have_doc_example(&i.inner),
+                    should_have_doc_example(self.ctx, &i),
                     should_have_docs,
                 );
             }
diff --git a/src/librustdoc/passes/doc_test_lints.rs b/src/librustdoc/passes/doc_test_lints.rs
index 78af9f9b856..1787d0a99d9 100644
--- a/src/librustdoc/passes/doc_test_lints.rs
+++ b/src/librustdoc/passes/doc_test_lints.rs
@@ -9,6 +9,7 @@ use crate::clean::*;
 use crate::core::DocContext;
 use crate::fold::DocFolder;
 use crate::html::markdown::{find_testable_code, ErrorCodes, Ignore, LangString};
+use rustc_middle::lint::LintSource;
 use rustc_session::lint;
 
 pub const CHECK_PRIVATE_ITEMS_DOC_TESTS: Pass = Pass {
@@ -56,8 +57,8 @@ impl crate::doctest::Tester for Tests {
     }
 }
 
-pub fn should_have_doc_example(item_kind: &clean::ItemEnum) -> bool {
-    !matches!(item_kind,
+pub fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> bool {
+    if matches!(item.inner,
         clean::StructFieldItem(_)
         | clean::VariantItem(_)
         | clean::AssocConstItem(_, _)
@@ -69,7 +70,13 @@ pub fn should_have_doc_example(item_kind: &clean::ItemEnum) -> bool {
         | clean::ImportItem(_)
         | clean::PrimitiveItem(_)
         | clean::KeywordItem(_)
-    )
+    ) {
+        return false;
+    }
+    let hir_id = cx.tcx.hir().local_def_id_to_hir_id(item.def_id.expect_local());
+    let (level, source) =
+        cx.tcx.lint_level_at_node(lint::builtin::MISSING_DOC_CODE_EXAMPLES, hir_id);
+    level != lint::Level::Allow || !matches!(source, LintSource::Node(..))
 }
 
 pub fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item) {
@@ -88,7 +95,7 @@ pub fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item) {
     if tests.found_tests == 0
         && rustc_feature::UnstableFeatures::from_environment().is_nightly_build()
     {
-        if should_have_doc_example(&item.inner) {
+        if should_have_doc_example(cx, &item) {
             debug!("reporting error for {:?} (hir_id={:?})", item, hir_id);
             let sp = span_of_attrs(&item.attrs).unwrap_or(item.source.span());
             cx.tcx.struct_span_lint_hir(
diff --git a/src/test/rustdoc-ui/coverage/allow_missing_docs.stderr b/src/test/rustdoc-ui/coverage/allow_missing_docs.stderr
new file mode 100644
index 00000000000..3d5b512d14d
--- /dev/null
+++ b/src/test/rustdoc-ui/coverage/allow_missing_docs.stderr
@@ -0,0 +1,20 @@
+warning: missing documentation for a struct
+  --> $DIR/allow_missing_docs.rs:36:5
+   |
+LL |     pub struct Bar {
+   |     ^^^^^^^^^^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/allow_missing_docs.rs:35:12
+   |
+LL |     #[warn(missing_docs)]
+   |            ^^^^^^^^^^^^
+
+warning: missing documentation for a struct field
+  --> $DIR/allow_missing_docs.rs:37:9
+   |
+LL |         pub f: u32,
+   |         ^^^^^^^^^^
+
+warning: 2 warnings emitted
+