Fix Module#const_source_location for autoload constants with direct requires

If an autoload exists for a constant, but the path for the autoload
was required, const_source_location would return [false, 0] instead
of the actual file and line. This fixes it by setting the appropriate
file and line in rb_const_set, and saving the file and line in
const_tbl_update before they get reset by current_autoload_data.

Fixes [Bug #18624]

2 files changed, 22 insertions, 2 deletions

diff --git a/test/ruby/test_autoload.rb b/test/ruby/test_autoload.rb
index bac6337eb9..bd875ec008 100644
--- a/test/ruby/test_autoload.rb
+++ b/test/ruby/test_autoload.rb
@@ -443,6 +443,23 @@ p Foo::Bar
     end
   end
 
+  def test_source_location_after_require
+    bug = "Bug18624"
+    Dir.mktmpdir('autoload') do |tmpdir|
+      path = "#{tmpdir}/test-#{bug}.rb"
+      File.write(path, "C::#{bug} = __FILE__\n")
+      assert_separately(%W[-I #{tmpdir}], "#{<<-"begin;"}\n#{<<-"end;"}")
+      begin;
+        class C; end
+        C.autoload(:Bug18624, #{path.dump})
+        require #{path.dump}
+        assert_equal [#{path.dump}, 1], C.const_source_location(#{bug.dump})
+        assert_equal #{path.dump}, C.const_get(#{bug.dump})
+        assert_equal [#{path.dump}, 1], C.const_source_location(#{bug.dump})
+      end;
+    end
+  end
+
   def test_no_memory_leak
     assert_no_memory_leak([], '', "#{<<~"begin;"}\n#{<<~'end;'}", 'many autoloads', timeout: 60)
     begin;
diff --git a/variable.c b/variable.c
index c3414d61c4..bf48e711f0 100644
--- a/variable.c
+++ b/variable.c
@@ -3264,6 +3264,7 @@ const_set(VALUE klass, ID id, VALUE val)
                 .value = val, .flag = CONST_PUBLIC,
                 /* fill the rest with 0 */
             };
+            ac.file = rb_source_location(&ac.line);
             const_tbl_update(&ac, false);
         }
     }
@@ -3337,6 +3338,8 @@ const_tbl_update(struct autoload_const *ac, int autoload_force)
         ce = (rb_const_entry_t *)value;
         if (ce->value == Qundef) {
             RUBY_ASSERT_CRITICAL_SECTION_ENTER();
+            VALUE file = ac->file;
+            int line = ac->line;
             struct autoload_data *ele = autoload_data_for_named_constant(klass, id, &ac);
 
             if (!autoload_force && ele) {
@@ -3350,8 +3353,8 @@ const_tbl_update(struct autoload_const *ac, int autoload_force)
                 autoload_delete(klass, id);
                 ce->flag = visibility;
                 RB_OBJ_WRITE(klass, &ce->value, val);
-                RB_OBJ_WRITE(klass, &ce->file, ac->file);
-                ce->line = ac->line;
+                RB_OBJ_WRITE(klass, &ce->file, file);
+                ce->line = line;
             }
             RUBY_ASSERT_CRITICAL_SECTION_LEAVE();
             return;