Fix exn signature range (#18982)

Author: ncave

src/Compiler/Symbols/SymbolHelpers.fs

@@ -94,7 +94,7 @@ module internal SymbolHelpers =
         | Item.Value vref  | Item.CustomBuilder (_, vref) -> Some (rangeOfValRef preferFlag vref)
         | Item.UnionCase(ucinfo, _)     -> Some (rangeOfUnionCaseInfo preferFlag ucinfo)
         | Item.ActivePatternCase apref -> Some (rangeOfValRef preferFlag apref.ActivePatternVal)
-        | Item.ExnCase tcref           -> Some tcref.Range
+        | Item.ExnCase tcref           -> Some (rangeOfEntityRef preferFlag tcref)
         | Item.AnonRecdField (_,_,_,m) -> Some m
         | Item.RecdField rfinfo        -> Some (rangeOfRecdFieldInfo preferFlag rfinfo)
         | Item.UnionCaseField (UnionCaseInfo (_, ucref), fieldIndex) -> Some (rangeOfRecdField preferFlag (ucref.FieldByIndex(fieldIndex)))

tests/FSharp.Compiler.ComponentTests/FSharpChecker/FindReferences.fs

@@ -266,11 +266,22 @@ val myFunc2: param: int -> int
             }
 
 module Exceptions =
-    let project() = SyntheticProject.Create(
-        { sourceFile "First" [] with ExtraSource = "exception MyException of string" },
-        { sourceFile "Second" [] with ExtraSource = """
+    let source1 = "exception MyException of string"
+    let signature1 = "exception MyException of string"
+
+    let source2 = """
 open ModuleFirst
-let foo x = raise (MyException "foo")""" })
+let foo x = raise (MyException "foo")
+"""
+    let project() = SyntheticProject.Create(
+        { sourceFile "First" [] with ExtraSource = source1 },
+        { sourceFile "Second" [] with ExtraSource = source2 })
+
+    let projectWithSignature() = SyntheticProject.Create(
+        { sourceFile "First" [] with
+            ExtraSource = source1
+            SignatureFile = Custom signature1 },
+        { sourceFile "Second" [] with ExtraSource = source2 })
 
     [<Fact>]
     let ``We find exception from definition`` () =
@@ -292,6 +303,28 @@ let foo x = raise (MyException "foo")""" })
             ])
         }
 
+    [<Fact>]
+    let ``We find exception from definition and signature`` () =
+        projectWithSignature().Workflow {
+            placeCursor "First" 6 21 "exception MyException of string" ["MyException"]
+            findAllReferences (expectToFind [
+                "FileFirst.fs", 6, 10, 21
+                "FileFirst.fsi", 2, 10, 21
+                "FileSecond.fs", 8, 19, 30
+            ])
+        }
+
+    [<Fact>]
+    let ``We find exception from usage and signature`` () =
+        projectWithSignature().Workflow {
+            placeCursor "Second" 8 30 "raise (MyException \"foo\")" ["MyException"]
+            findAllReferences (expectToFind [
+                "FileFirst.fs", 6, 10, 21
+                "FileFirst.fsi", 2, 10, 21
+                "FileSecond.fs", 8, 19, 30
+            ])
+        }
+
 module Attributes =
 
     let project() = SyntheticProject.Create(