Use spans pointing at the inside of a rustdoc attribute

src/librustdoc/clean/mod.rs

@@ -1191,30 +1191,60 @@ fn resolution_failure(
     link_range: Option<Range<usize>>,
 ) {
     let sp = span_of_attrs(attrs);
-    let mut diag = cx.sess()
-        .struct_span_warn(sp, &format!("[{}] cannot be resolved, ignoring it...", path_str));
+    let msg = format!("`[{}]` cannot be resolved, ignoring it...", path_str);
 
-    if let Some(link_range) = link_range {
+    let code_dox = sp.to_src(cx);
+
+    let doc_comment_padding = 3;
+    let mut diag = if let Some(link_range) = link_range {
         // blah blah blah\nblah\nblah [blah] blah blah\nblah blah
         //                       ^    ~~~~~~
         //                       |    link_range
         //                       last_new_line_offset
 
-        let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
-        let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
-
-        // Print the line containing the `link_range` and manually mark it with '^'s
-        diag.note(&format!(
-            "the link appears in this line:\n\n{line}\n{indicator: <before$}{indicator:^<found$}",
-            line=line,
-            indicator="",
-            before=link_range.start - last_new_line_offset,
-            found=link_range.len(),
-        ));
-    } else {
+        let mut diag;
+        if dox.lines().count() == code_dox.lines().count() {
+            let line_offset = dox[..link_range.start].lines().count();
+            // The span starts in the `///`, so we don't have to account for the leading whitespace
+            let code_dox_len = if line_offset <= 1 {
+                doc_comment_padding
+            } else {
+                // The first `///`
+                doc_comment_padding +
+                    // Each subsequent leading whitespace and `///`
+                    code_dox.lines().skip(1).take(line_offset - 1).fold(0, |sum, line| {
+                        sum + doc_comment_padding + line.len() - line.trim().len()
+                    })
+            };
 
-    }
+            // Extract the specific span
+            let sp = sp.from_inner_byte_pos(
+                link_range.start + code_dox_len,
+                link_range.end + code_dox_len,
+            );
 
+            diag = cx.sess().struct_span_warn(sp, &msg);
+            diag.span_label(sp, "cannot be resolved, ignoring");
+        } else {
+            diag = cx.sess().struct_span_warn(sp, &msg);
+
+            let last_new_line_offset = dox[..link_range.start].rfind('\n').map_or(0, |n| n + 1);
+            let line = dox[last_new_line_offset..].lines().next().unwrap_or("");
+
+            // Print the line containing the `link_range` and manually mark it with '^'s
+            diag.note(&format!(
+                "the link appears in this line:\n\n{line}\n\
+                 {indicator: <before$}{indicator:^<found$}",
+                line=line,
+                indicator="",
+                before=link_range.start - last_new_line_offset,
+                found=link_range.len(),
+            ));
+        }
+        diag
+    } else {
+        cx.sess().struct_span_warn(sp, &msg)
+    };
     diag.emit();
 }
 

src/test/rustdoc-ui/intra-links-warning.rs

@@ -10,10 +10,48 @@
 
 // compile-pass
 
-//! Test with [Foo::baz], [Bar::foo], ...
-//!
-//! and [Uniooon::X].
+       //! Test with [Foo::baz], [Bar::foo], ...
+     //! , [Uniooon::X] and [Qux::Z].
+       //!
+      //! , [Uniooon::X] and [Qux::Z].
 
+       /// [Qux:Y]
 pub struct Foo {
     pub bar: usize,
 }
+
+/// Foo
+/// bar [BarA] bar
+/// baz
+pub fn a() {}
+
+/**
+ * Foo
+ * bar [BarB] bar
+ * baz
+ */
+pub fn b() {}
+
+/** Foo
+
+bar [BarC] bar
+baz
+
+    let bar_c_1 = 0;
+    let bar_c_2 = 0;
+    let g = [bar_c_1];
+    let h = g[bar_c_2];
+
+*/
+pub fn c() {}
+
+#[doc = "Foo\nbar [BarD] bar\nbaz"]
+pub fn d() {}
+
+macro_rules! f {
+    ($f:expr) => {
+        #[doc = $f]
+        pub fn f() {}
+    }
+}
+f!("Foo\nbar [BarF] bar\nbaz");

src/test/rustdoc-ui/intra-links-warning.stderr

@@ -1,39 +1,105 @@
-warning: [Foo::baz] cannot be resolved, ignoring it...
-  --> $DIR/intra-links-warning.rs:13:1
+warning: `[Foo::baz]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:13:23
    |
-13 | / //! Test with [Foo::baz], [Bar::foo], ...
-14 | | //!
-15 | | //! and [Uniooon::X].
-   | |_____________________^
+13 |        //! Test with [Foo::baz], [Bar::foo], ...
+   |                       ^^^^^^^^ cannot be resolved, ignoring
+
+warning: `[Bar::foo]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:13:35
+   |
+13 |        //! Test with [Foo::baz], [Bar::foo], ...
+   |                                   ^^^^^^^^ cannot be resolved, ignoring
+
+warning: `[Uniooon::X]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:14:13
+   |
+14 |      //! , [Uniooon::X] and [Qux::Z].
+   |             ^^^^^^^^^^ cannot be resolved, ignoring
+
+warning: `[Qux::Z]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:14:30
+   |
+14 |      //! , [Uniooon::X] and [Qux::Z].
+   |                              ^^^^^^ cannot be resolved, ignoring
+
+warning: `[Uniooon::X]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:16:14
+   |
+16 |       //! , [Uniooon::X] and [Qux::Z].
+   |              ^^^^^^^^^^ cannot be resolved, ignoring
+
+warning: `[Qux::Z]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:16:31
+   |
+16 |       //! , [Uniooon::X] and [Qux::Z].
+   |                               ^^^^^^ cannot be resolved, ignoring
+
+warning: `[Qux:Y]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:18:13
+   |
+18 |        /// [Qux:Y]
+   |             ^^^^^ cannot be resolved, ignoring
+
+warning: `[BarA]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:24:10
+   |
+24 | /// bar [BarA] bar
+   |          ^^^^ cannot be resolved, ignoring
+
+warning: `[BarB]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:28:1
+   |
+28 | / /**
+29 | |  * Foo
+30 | |  * bar [BarB] bar
+31 | |  * baz
+32 | |  */
+   | |___^
+   |
+   = note: the link appears in this line:
+
+            bar [BarB] bar
+                 ^^^^
+
+warning: `[BarC]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:35:1
+   |
+35 | / /** Foo
+36 | |
+37 | | bar [BarC] bar
+38 | | baz
+...  |
+44 | |
+45 | | */
+   | |__^
    |
    = note: the link appears in this line:
 
-            Test with [Foo::baz], [Bar::foo], ...
-                       ^^^^^^^^
+           bar [BarC] bar
+                ^^^^
 
-warning: [Bar::foo] cannot be resolved, ignoring it...
-  --> $DIR/intra-links-warning.rs:13:1
+warning: `[BarD]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:48:1
    |
-13 | / //! Test with [Foo::baz], [Bar::foo], ...
-14 | | //!
-15 | | //! and [Uniooon::X].
-   | |_____________________^
+48 | #[doc = "Foo/nbar [BarD] bar/nbaz"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: the link appears in this line:
 
-            Test with [Foo::baz], [Bar::foo], ...
-                                   ^^^^^^^^
+           bar [BarD] bar
+                ^^^^
 
-warning: [Uniooon::X] cannot be resolved, ignoring it...
-  --> $DIR/intra-links-warning.rs:13:1
+warning: `[BarF]` cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:53:9
    |
-13 | / //! Test with [Foo::baz], [Bar::foo], ...
-14 | | //!
-15 | | //! and [Uniooon::X].
-   | |_____________________^
+53 |         #[doc = $f]
+   |         ^^^^^^^^^^^
+...
+57 | f!("Foo/nbar [BarF] bar/nbaz");
+   | ------------------------------- in this macro invocation
    |
    = note: the link appears in this line:
 
-            and [Uniooon::X].
-                 ^^^^^^^^^^
+           bar [BarF] bar
+                ^^^^