From 9c6068f026fb14d6baa929a2bea635564fcffd20 Mon Sep 17 00:00:00 2001
From: Olle Jonsson <olle.jonsson@gmail.com>
Date: Sat, 16 Apr 2016 23:20:36 +0200
Subject: [PATCH] Avoid nil bug in detect_since_tag

---
 .../generator/generator_tags.rb               | 15 ++++----
 spec/unit/generator/generator_tags_spec.rb    | 37 ++++++++++---------
 2 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/lib/github_changelog_generator/generator/generator_tags.rb b/lib/github_changelog_generator/generator/generator_tags.rb
index fa0f40f..97e43b0 100644
--- a/lib/github_changelog_generator/generator/generator_tags.rb
+++ b/lib/github_changelog_generator/generator/generator_tags.rb
@@ -54,13 +54,14 @@ module GitHubChangelogGenerator
 
     # @return [Object] try to find newest tag using #Reader and :base option if specified otherwise returns nil
     def detect_since_tag
-      @since_tag ||= @options[:since_tag]
-      if @since_tag.nil? && @options[:base] && File.file?(@options[:base])
-        reader = GitHubChangelogGenerator::Reader.new
-        content = reader.read(@options[:base])
-        @since_tag = content[0]["version"] if content.count && content
-      end
-      @since_tag
+      @since_tag ||= @options.fetch(:since_tag) { version_of_first_item }
+    end
+
+    def version_of_first_item
+      return unless File.file?(@options[:base].to_s)
+
+      sections = GitHubChangelogGenerator::Reader.new.read(@options[:base])
+      sections.first["version"] if sections && sections.any?
     end
 
     # Return tags after filtering tags in lists provided by option: --between-tags & --exclude-tags
diff --git a/spec/unit/generator/generator_tags_spec.rb b/spec/unit/generator/generator_tags_spec.rb
index 04c9b50..c4aec07 100644
--- a/spec/unit/generator/generator_tags_spec.rb
+++ b/spec/unit/generator/generator_tags_spec.rb
@@ -206,7 +206,7 @@ describe GitHubChangelogGenerator::Generator do
         @generator.instance_variable_set :@fetcher, mock
       end
       subject do
-        of_tag = @generator.get_time_of_tag tag_mash_with_name("valid_tag")
+        of_tag = @generator.get_time_of_tag(tag_mash_with_name("valid_tag"))
         of_tag
       end
       it { is_expected.to be_a_kind_of(Time) }
@@ -215,31 +215,32 @@ describe GitHubChangelogGenerator::Generator do
   end
 
   describe "#sort_tags_by_date" do
-    time1 = Time.now
-    time2 = Time.now
-    time3 = Time.now
+    let(:time1) { Time.now }
+    let(:time2) { Time.now }
+    let(:time3) { Time.now }
+
     before(:all) do
       @generator = GitHubChangelogGenerator::Generator.new
     end
+
+    before do
+      @generator.instance_variable_set(:@tag_times_hash, "valid_tag1" => time1,
+                                                         "valid_tag2" => time2,
+                                                         "valid_tag3" => time3)
+    end
+
+    subject do
+      @generator.sort_tags_by_date(tags)
+    end
     context "sort unsorted tags" do
-      tags = tags_mash_from_strings %w(valid_tag1 valid_tag2 valid_tag3)
-      before do
-        @generator.instance_variable_set :@tag_times_hash, "valid_tag1" => time1, "valid_tag2" => time2, "valid_tag3" => time3
-      end
-      subject do
-        @generator.sort_tags_by_date tags
-      end
+      let(:tags) { tags_mash_from_strings %w(valid_tag1 valid_tag2 valid_tag3) }
+
       it { is_expected.to be_a_kind_of(Array) }
       it { is_expected.to match_array(tags.reverse!) }
     end
     context "sort sorted tags" do
-      tags = tags_mash_from_strings %w(valid_tag3 valid_tag2 valid_tag1)
-      before do
-        @generator.instance_variable_set :@tag_times_hash, "valid_tag1" => time1, "valid_tag2" => time2, "valid_tag3" => time3
-      end
-      subject do
-        @generator.sort_tags_by_date tags
-      end
+      let(:tags) { tags_mash_from_strings %w(valid_tag3 valid_tag2 valid_tag1) }
+
       it { is_expected.to be_a_kind_of(Array) }
       it { is_expected.to match_array(tags) }
     end