From f61c7370e545dc8ccb9577a8a64146103e94a167 Mon Sep 17 00:00:00 2001
From: lewisnyman <hello@lewisnyman.co.uk>
Date: Tue, 31 Jul 2018 13:13:38 +0100
Subject: [PATCH] Add configuration options to remove default pipeline
 functions

---
 README.md                                     | 9 ++++++++-
 lib/middleman-search/extension.rb             | 1 +
 lib/middleman-search/search-index-resource.rb | 6 ++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 78a19e4..498abc8 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ activate :search do |search|
   search.resources = ['blog/', 'index.html', 'contactus/index.html']
 
   search.index_path = 'search/lunr-index.json' # defaults to `search.json`
-  
+
   search.lunr_dirs = ['source/vendor/lunr-custom/'] # optional alternate paths where to look for lunr js files
 
   search.language = 'es' # defaults to 'en'
@@ -123,6 +123,13 @@ Note that if you add a function to the pipeline, it will also be loaded when de-
 <%= search_lunr_js_pipeline %>
 ```
 
+You can also remove pipeline functions that Lunr.js enables by default: trimmer, stemmer, and stopWordFilter.
+
+```ruby
+search.pipeline_remove = [
+  'stopWordFilter'
+]
+```
 
 ## Index file
 
diff --git a/lib/middleman-search/extension.rb b/lib/middleman-search/extension.rb
index e05b32f..51bf0e9 100644
--- a/lib/middleman-search/extension.rb
+++ b/lib/middleman-search/extension.rb
@@ -8,6 +8,7 @@ class SearchExtension < Middleman::Extension
     option :before_index, nil, 'Callback to execute before indexing a document'
     option :index_path, 'search.json', 'Index file path'
     option :pipeline, {}, 'Javascript pipeline functions to use in lunr index'
+    option :pipeline_remove, {}, 'Default pipeline functions to remove'
     option :cache, false, 'Avoid the cache to be rebuilt on every request in development mode'
     option :language, 'en', 'Language code ("es", "fr") to use when indexing site\'s content'
     option :lunr_dirs, [], 'Directories in which to look for custom lunr.js files'
diff --git a/lib/middleman-search/search-index-resource.rb b/lib/middleman-search/search-index-resource.rb
index daae8d5..01296ac 100644
--- a/lib/middleman-search/search-index-resource.rb
+++ b/lib/middleman-search/search-index-resource.rb
@@ -8,6 +8,7 @@ def initialize(store, path, options)
         @fields = options[:fields]
         @callback = options[:before_index]
         @pipeline = options[:pipeline]
+        @pipeline_remove = options[:pipeline_remove]
         @cache_index = options[:cache]
         @language = options[:language]
         @lunr_dirs = options[:lunr_dirs] + [File.expand_path("../../../vendor/assets/javascripts/", __FILE__)]
@@ -52,6 +53,11 @@ def build_index
         # Use autogenerated id field as reference
         source << "this.ref('id');"
 
+        # Remove default pipeline filters
+        @pipeline_remove.each do |name|
+          source << "this.pipeline.remove(lunr.#{name});"
+        end
+
         # Add functions to pipeline (just registering them isn't enough)
         @pipeline.each do |name, function|
           source << "this.pipeline.add(lunr.Pipeline.registeredFunctions.#{name});"