Merge pull request #5286 from yn-misaki/fix_backtrace_error

Fix GraphQL backtrace handling for inline fragments

Author: rmosolgo

lib/graphql/backtrace/table.rb

@@ -78,30 +78,53 @@ def rows
             end
           end
 
-
           object = result.graphql_application_value.object.inspect
-          ast_node = result.graphql_selections.find { |s| s.alias == last_part || s.name == last_part }
-          field_defn = query.get_field(result.graphql_result_type, ast_node.name)
-          args = query.arguments_for(ast_node, field_defn).to_h
-          field_path = field_defn.path
-          if ast_node.alias
-            field_path += " as #{ast_node.alias}"
+          ast_node = nil
+          result.graphql_selections.each do |s|
+            found_ast_node = find_ast_node(s, last_part)
+            if found_ast_node
+              ast_node = found_ast_node
+              break
+            end
           end
 
-          rows << [
-            ast_node.position.join(":"),
-            field_path,
-            "#{object}",
-            args.inspect,
-            inspect_result(@override_value)
-          ]
+          if ast_node
+            field_defn = query.get_field(result.graphql_result_type, ast_node.name)
+            args = query.arguments_for(ast_node, field_defn).to_h
+            field_path = field_defn.path
+            if ast_node.alias
+              field_path += " as #{ast_node.alias}"
+            end
+
+            rows << [
+              ast_node.position.join(":"),
+              field_path,
+              "#{object}",
+              args.inspect,
+              inspect_result(@override_value)
+            ]
+          end
 
           rows << HEADERS
           rows.reverse!
           rows
         end
       end
 
+      def find_ast_node(node, last_part)
+        return nil unless node
+        return node if node.respond_to?(:alias) && node.respond_to?(:name) && (node.alias == last_part || node.name == last_part)
+        return nil unless node.respond_to?(:selections)
+        return nil if node.selections.nil? || node.selections.empty?
+
+        node.selections.each do |child|
+          child_ast_node = find_ast_node(child, last_part)
+          return child_ast_node if child_ast_node
+        end
+
+        nil
+      end
+
       # @return [String]
       def render_table(rows)
         max = Array.new(HEADERS.length, MIN_COL_WIDTH)

spec/graphql/backtrace_spec.rb

@@ -159,6 +159,43 @@ def execute_multiplex(multiplex:)
       assert_includes err.message, "more lines"
     end
 
+    it "annotates crashes from user code when using inline fragments" do
+      err = assert_raises(GraphQL::Backtrace::TracedError) {
+        backtrace_schema.execute <<-GRAPHQL, root_value: "Root"
+        query($msg: String = \"Boom\") {
+          field1 {
+            ... on Thing {
+              boomError: raiseField(message: $msg)
+            }
+          }
+        }
+        GRAPHQL
+      }
+
+      # GraphQL backtrace is present
+      expected_graphql_backtrace = [
+        "4:15: Thing.raiseField as boomError",
+        "2:11: Query.field1",
+        "1:9: query",
+      ]
+      assert_equal expected_graphql_backtrace, err.graphql_backtrace
+
+      hash_inspect = { message: "Boom" }.inspect
+      # The message includes the GraphQL context
+      rendered_table = [
+        'Loc  | Field                         | Object     | ' + "Arguments".ljust(hash_inspect.size) + ' | Result',
+        '4:15 | Thing.raiseField as boomError | :something | ' + hash_inspect + ' | #<RuntimeError: This is broken: Boom>',
+        '2:11 | Query.field1                  | "Root"     | ' + "{}".ljust(hash_inspect.size) + ' | {}',
+        '1:9  | query                         | "Root"     | ' + {"msg" => "Boom"}.inspect.ljust(hash_inspect.size) + ' | {field1: {...}}',
+      ].join("\n")
+
+      assert_includes err.message, "\n" + rendered_table
+      # The message includes the original error message
+      assert_includes err.message, "This is broken: Boom"
+      assert_includes err.message, "spec/graphql/backtrace_spec.rb:49", "It includes the original backtrace"
+      assert_includes err.message, "more lines"
+    end
+
     it "annotates errors from Query#result" do
       query_str = "query StrField { field2 { strField } __typename }"
       context = { backtrace: true }