add ignore_file configuration option

README.md

@@ -12,13 +12,23 @@ Brakeman [Confidence](https://github.com/presidentbeef/brakeman#confidence-level
 messages generated by Pronto. High confidence maps to fatal, medium confidence maps to warning, and low confidence maps
 to info.
 
-## Run all checks
-
+# Options
 Brakeman also includes some optional checks and by setting the following in your `.pronto.yml` you can run every check included in the gem:
 
+## Run all checks
+
 ```yaml
 brakeman:
   run_all_checks: true
 ```
 
 (This is the equivalent of running `brakeman -A` on the command line.)
+
+## Ignore file
+
+```yaml
+brakeman:
+  ignore_file: '.brakeman'
+```
+
+(This is the equivalent of running `brakeman -i IGNOREFILE` on the command line.)

lib/pronto/brakeman.rb

@@ -14,7 +14,8 @@ def run
       output = ::Brakeman.run(app_path: repo_path,
                               output_formats: [:to_s],
                               only_files: files,
-                              run_all_checks: run_all_checks?)
+                              run_all_checks: run_all_checks?,
+                              ignore_file: ignore_file)
        messages_for(patches, output).compact
     rescue ::Brakeman::NoApplication
       []
@@ -61,6 +62,10 @@ def run_all_checks?
       pronto_brakeman_config['run_all_checks']
     end
 
+    def ignore_file
+      pronto_brakeman_config['ignore_file']
+    end
+
     def pronto_brakeman_config
       pronto_brakeman_config ||= Pronto::ConfigFile.new.to_h['brakeman'] || {}
     end