3 files changed, 106 insertions(+), 1 deletions(-)

M .gitignore
A spec/extract_jekyll_front_matter_spec.cr
A src/extract_jekyll_front_matter.cr

@@ 1,2 1,3 @@
 bin
-lib>
\ No newline at end of file
+lib
+.DS_store<
\ No newline at end of file

@@ 0,0 1,73 @@
+require "spec"
+
+require "../src/extract_jekyll_front_matter.cr"
+
+describe "Extracting Jekyll front matter" do
+  it "Extracts the simple front matter" do
+    input = <<-HEREDOC
+		---
+		title: hello
+		---
+		some
+		other text
+		HEREDOC
+    output = extract_jekyll_front_matter(input)
+
+    output[:front_matter].should eq({"title" => "hello"})
+    output[:doc].should eq(<<-EXPECTED_DOC
+    	some
+    	other text
+    	EXPECTED_DOC
+    )
+  end
+
+  it "Extracts the more advanced front matter" do
+    input = <<-HEREDOC
+		---
+		title: hello
+		there: world
+		this:
+		- is
+		- a list
+		---
+		some
+		other text
+		HEREDOC
+    output = extract_jekyll_front_matter(input)
+
+    output[:front_matter].should eq({"title" => "hello",
+                                     "there" => "world",
+                                     "this"  => ["is", "a list"]})
+    output[:doc].should eq(<<-EXPECTED_DOC
+    	some
+    	other text
+    	EXPECTED_DOC
+    )
+  end
+
+  it "Extracts the doc alone if there is no front matter" do
+    input = <<-HEREDOC
+		some
+		other text
+		HEREDOC
+    output = extract_jekyll_front_matter(input)
+
+    output[:front_matter].as_nil.nil?.should be_true
+    output[:doc].should eq(<<-EXPECTED_DOC
+    	some
+    	other text
+    	EXPECTED_DOC
+    )
+  end
+
+  it "Detects when front matter is not finished properly" do
+    input = <<-HEREDOC
+   		---
+		some
+		other text
+		HEREDOC
+    expect_raises(Exception, "Front matter not closed") do
+      output = extract_jekyll_front_matter(input)
+    end
+  end
+end

@@ 0,0 1,31 @@
+require "yaml"
+
+def extract_jekyll_front_matter(input : String)
+  step = :first_line
+  front_matter = String::Builder.new
+  markdown = String::Builder.new
+
+  lines = input.strip.each_line do |line|
+    case step
+    when :first_line
+      if (line == "---")
+        step = :front_matter
+      else
+        step = :markdown
+        markdown << line << "\n"
+      end
+    when :front_matter
+      if line == "---"
+        step = :markdown
+      else
+        front_matter << line << "\n"
+      end
+    when :markdown
+      markdown << line << "\n"
+    end
+  end
+  raise "Front matter not closed" if step == :front_matter
+
+  return {front_matter: YAML.parse(front_matter.to_s),
+          doc:          markdown.to_s.strip}
+end