BE: track related info in declarative tests

Summary:
Our declarative tests allow us to add annotations for expected diagnostics, so we can clearly see and check what is generated.

But at present there is no way to check any related information for a diagnostic.

This diff adds that capability, showing related information together with the FileId and range each refers to.

Reviewed By: robertoaloi

Differential Revision: D87316965

fbshipit-source-id: ea7db2980b11950c3552befec7b666665ceef84b

.llms/rules/elp_development.md

@@ -168,6 +168,12 @@ directly in test code:
 - **Left-margin annotation**: `%%<^^^ text` - Annotation starts at `%%` position
   instead of first `^`
 - **Multiline annotations**: Use continuation lines with `%%   | next line`
+  - Continuation lines are particularly useful for diagnostics with related information:
+    ```erlang
+    foo() -> syntax error oops.
+    %%              ^^^^^ error: P1711: syntax error before: error
+    %%                  | Related info: 0:45-50 function foo/0 undefined
+    ```
 
 #### Example Test Fixture
 

crates/ide/src/diagnostics.rs

@@ -3433,6 +3433,9 @@ baz(1)->4.
              -spec foo() -> ok.
              foo( -> ok. %%
              %%  ^ error: W0004: Missing ')'
+             %%  | Related info: 0:21-43 function foo/0 undefined
+             %%  | Related info: 0:74-79 function foo/0 undefined
+             %%  | Related info: 0:82-99 spec for undefined function foo/0
             "#,
         );
     }
@@ -3463,6 +3466,7 @@ baz(1)->4.
 
              foo() -> syntax error oops.
              %%              ^^^^^ error: P1711: syntax error before: error
+             %%                  | Related info: 0:25-30 function foo/0 undefined
             "#,
         );
     }
@@ -3766,6 +3770,7 @@ baz(1)->4.
                      \~"\"\\µA\"" = \~/"\\µA"/
                      X = 3.
                   %% ^ error: P1711: syntax error before: X
+                  %% | Related info: 0:32-37 function foo/0 undefined
             "#,
         );
     }

crates/ide/src/diagnostics/head_mismatch.rs

@@ -396,6 +396,7 @@ mod tests {
     foo(0) -> 1;
     boo(1) -> 2.
  %% ^^^ 💡 error: P1700: head mismatch 'boo' vs 'foo'
+ %%   | Related info: 0:21-24 Mismatched clause name
             "#,
         );
         check_fix(
@@ -421,6 +422,7 @@ mod tests {
                 ok;
             fooX(_X) ->
          %% ^^^^ 💡 error: P1700: head mismatch 'fooX' vs 'food'
+         %%    | Related info: 0:21-25 Mismatched clause name
                 no.
 
             bar() ->
@@ -450,6 +452,7 @@ mod tests {
     -module(main).
     foo(0) -> 1;
  %% ^^^ 💡 error: P1700: head mismatch 'foo' vs 'boo'
+ %%   | Related info: 0:37-40 Mismatched clause name
     boo(1) -> 2;
     boo(2) -> 3.
             "#,
@@ -478,6 +481,7 @@ mod tests {
     foo(0) -> 1;
     foo(1,0) -> 2.
  %% ^^^^^^^^^^^^^ error: P1700: head arity mismatch 2 vs 1
+ %%             | Related info: 0:21-32 Mismatched clause
             "#,
         );
     }
@@ -490,6 +494,7 @@ mod tests {
     foo(2,0) -> 3;
     foo(0) -> 1;
  %% ^^^^^^^^^^^ error: P1700: head arity mismatch 1 vs 2
+ %%           | Related info: 0:21-34 Mismatched clause
     foo(1,0) -> 2.
             "#,
         );
@@ -516,6 +521,7 @@ mod tests {
            (0) -> ok;
            A(N) -> ok
         %% ^ 💡 error: P1700: head mismatch 'A' vs ''
+        %% | Related info: 0:44-53 Mismatched clause name
        end,
        F().
             "#,

crates/ide/src/diagnostics/misspelled_attribute.rs

@@ -164,6 +164,7 @@ mod tests {
     -module(main).
     -dyalizer({nowarn_function, f/0}).
  %%% ^^^^^^^^ 💡 error: W0013: misspelled attribute, saw 'dyalizer' but expected 'dialyzer'
+ %%%        | Related info: 0:22-30 Misspelled attribute
             "#,
         );
         check_fix(
@@ -224,6 +225,7 @@ mod tests {
     -module(main).
     -module_doc """
 %%%  ^^^^^^^^^^ 💡 error: W0013: misspelled attribute, saw 'module_doc' but expected 'moduledoc'
+%%%           | Related info: 0:24-34 Misspelled attribute
     Hola
     """.
             "#,
@@ -237,6 +239,7 @@ mod tests {
     -module(main).
     -docs """
 %%%  ^^^^ 💡 error: W0013: misspelled attribute, saw 'docs' but expected 'doc'
+%%%     | Related info: 0:24-28 Misspelled attribute
     Hola
     """.
     foo() -> ok.

crates/ide/src/diagnostics/unused_include.rs

@@ -581,6 +581,7 @@ foo() -> ok.
 %% The following shows up as a wild attribute, which we regard as being used.
    -defin e(X, 1).
 %%  ^^^^^ 💡 error: W0013: misspelled attribute, saw 'defin' but expected 'define'
+%%    | Related info: 1:82-87 Misspelled attribute
 
 -def ine(Y, 2).
 "#,

crates/ide/src/tests.rs

@@ -401,6 +401,23 @@ fn convert_diagnostics_to_annotations(diagnostics: Vec<Diagnostic>) -> Vec<(Text
             annotation.push_str(&d.code.as_code());
             annotation.push_str(": ");
             annotation.push_str(&convert_diagnostic_message(&d));
+
+            // Append related info to the annotation
+            if let Some(related_info) = &d.related_info {
+                // Sort related info alphabetically by message for consistent test output
+                let mut sorted_info = related_info.clone();
+                sorted_info.sort_by(|a, b| a.message.cmp(&b.message));
+                for info in sorted_info {
+                    annotation.push_str(&format!(
+                        "\nRelated info: {}:{}-{} {}",
+                        info.file_id.index(),
+                        u32::from(info.range.start()),
+                        u32::from(info.range.end()),
+                        info.message
+                    ));
+                }
+            }
+
             (d.range, annotation)
         })
         .collect::<Vec<_>>();

crates/project_model/src/test_fixture.rs

@@ -472,6 +472,14 @@ pub fn extract_tags(mut text: &str, tag: &str) -> (Vec<(TextRange, Option<String
 /// %%   | second line
 /// ```
 ///
+/// This is useful for representing diagnostics with related information:
+///
+/// ```not_rust
+/// foo() -> syntax error oops.
+/// %%              ^^^^^ error: P1711: syntax error before: error
+/// %%                  | Related info: 0:25-30 function foo/0 undefined
+/// ```
+///
 /// Annotations point to the last line that actually was long enough for the
 /// range, not counting annotations themselves. So overlapping annotations are
 /// possible:
@@ -551,10 +559,16 @@ pub fn extract_annotations(text: &str) -> (Vec<(TextRange, String)>, String) {
                             if !res.is_empty() {
                                 offset += annotation_offset;
                                 this_line_annotations.push((offset, res.len() - 1));
-                                let &(_, idx) = prev_line_annotations
+                                // Try to find a previous annotation at the same offset
+                                let idx = if let Some(&(_, idx)) = prev_line_annotations
                                     .iter()
                                     .find(|&&(off, _idx)| off == offset)
-                                    .unwrap();
+                                {
+                                    idx
+                                } else {
+                                    // If no exact offset match, append to the most recent annotation
+                                    res.len() - 1
+                                };
                                 res[idx].1.push('\n');
                                 res[idx].1.push_str(&content);
                             }