Add ContentExcerpt feature for pages

src/Pretzel.Logic/Templating/Context/Page.cs

@@ -20,6 +20,7 @@ public Page()
         public IEnumerable<string> Categories { get; set; }
         public IEnumerable<string> Tags { get; set; }
         public string Content { get; set; }
+        public string Excerpt { get; set; }
         public string Filepath { get; set; }
         public IDictionary<string, object> Bag { get; set; }
         public IEnumerable<Page> DirectoryPages { get; set; }

src/Pretzel.Logic/Templating/Context/PageContext.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.IO;
 
@@ -32,6 +33,8 @@ public PageContext(PageContext context)
 
         public string Content { get; set; }
 
+        public string Excerpt { get; set; }
+
         public SiteContext Site { get; private set; }
 
         public Page Page { get; set; }
@@ -77,9 +80,9 @@ public static PageContext FromPage(SiteContext siteContext, Page page, string ou
                 context.Title = siteContext.Title;
 
             context.Content = page.Content;
+            context.Excerpt = page.Excerpt;
             context.Bag = page.Bag;
             context.Bag["id"] = page.Id;
-            context.Bag.Add("url", page.Url);
             return context;
         }
     }

src/Pretzel.Logic/Templating/Context/SiteContext.cs

@@ -5,8 +5,11 @@ namespace Pretzel.Logic.Templating.Context
 {
     public class SiteContext
     {
+        private const string ExcerptSeparatorDefault = "<!--more-->";
+
         private string engine;
         private string title;
+        private string excerptSeparator = ExcerptSeparatorDefault;
 
         public IDictionary<string, object> Config { get; set; }
         public string SourceFolder { get; set; }
@@ -32,6 +35,19 @@ public string Title
             set { title = value; }
         }
 
+        public string ExcerptSeparator
+        {
+            get
+            {
+                if (Config.Keys.Contains("excerpt_separator"))
+                {
+                    excerptSeparator = Config["excerpt_separator"].ToString();
+                }
+                return excerptSeparator;
+            }
+            set { excerptSeparator = value; }
+        }
+
         public string Engine
         {
             get

src/Pretzel.Logic/Templating/Context/SiteContextGenerator.cs

@@ -222,6 +222,10 @@ private Page CreatePage(SiteContext context, IDictionary<string, object> config,
                     return pageCache[file];
                 var contents = SafeReadContents(file);
                 var header = contents.YamlHeader();
+                var content = RenderContent(file, contents, header);
+                var excerptSeparator = header.ContainsKey("excerpt_separator") 
+                    ? header["excerpt_separator"].ToString() 
+                    : context.ExcerptSeparator;
 
                 if (header.ContainsKey("published") && header["published"].ToString().ToLower() == "false")
                 {
@@ -232,11 +236,13 @@ private Page CreatePage(SiteContext context, IDictionary<string, object> config,
                                 {
                                     Title = header.ContainsKey("title") ? header["title"].ToString() : "this is a post",
                                     Date = header.ContainsKey("date") ? DateTime.Parse(header["date"].ToString()) : file.Datestamp(),
-                                    Content = RenderContent(file, contents, header),
+                                    Content = content,
+                                    Excerpt = GetContentExcerpt(content, excerptSeparator),
                                     Filepath = isPost ? GetPathWithTimestamp(context.OutputFolder, file) : GetFilePathForPage(context, file),
                                     File = file,
                                     Bag = header,
                                 };
+                page.Bag["excerpt"] = page.Excerpt;
 
                 // resolve categories and tags
                 if (isPost)
@@ -336,6 +342,12 @@ private string RenderContent(string file, string contents, IDictionary<string, o
             return html;
         }
 
+        private static string GetContentExcerpt(string content, string excerptSeparator)
+        {
+            var index = content.IndexOf(excerptSeparator, StringComparison.InvariantCulture);
+            return index == -1 ? content : content.Substring(0, index);
+        }
+
         private string SafeReadLine(string file)
         {
             string postFirstLine;

src/Pretzel.Tests/Templating/Context/SiteContextGeneratorTests.cs

@@ -735,7 +735,7 @@ public void page_default_values()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Pages[0].Content);
             Assert.Equal(@"C:\TestSite\_site\SomeFile.md", siteContext.Pages[0].Filepath);
             Assert.Equal(@"C:\TestSite\SomeFile.md", siteContext.Pages[0].File);
-            Assert.Equal(2, siteContext.Pages[0].Bag.Count);
+            Assert.Equal(3, siteContext.Pages[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Pages[0].Bag["param"]);
         }
 
@@ -759,7 +759,7 @@ public void page_metadata_values()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Pages[0].Content);
             Assert.Equal(@"C:\TestSite\_site\SomeFile.md", siteContext.Pages[0].Filepath);
             Assert.Equal(@"C:\TestSite\SomeFile.md", siteContext.Pages[0].File);
-            Assert.Equal(3, siteContext.Pages[0].Bag.Count);
+            Assert.Equal(4, siteContext.Pages[0].Bag.Count); // title, date, param, excerpt
             Assert.Equal("value", siteContext.Pages[0].Bag["param"]);
             Assert.Equal("my title", siteContext.Pages[0].Bag["title"]);
             Assert.Equal(currentDate, siteContext.Pages[0].Bag["date"]);
@@ -784,7 +784,7 @@ public void page_with_date_in_title()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Pages[0].Content);
             Assert.Equal(string.Format(@"C:\TestSite\_site\{0}-SomeFile.md", currentDate.Replace("/", "-")), siteContext.Pages[0].Filepath);
             Assert.Equal(filePath, siteContext.Pages[0].File);
-            Assert.Equal(2, siteContext.Pages[0].Bag.Count);
+            Assert.Equal(3, siteContext.Pages[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Pages[0].Bag["param"]);
         }
 
@@ -807,7 +807,7 @@ public void page_with_false_date_in_title()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Pages[0].Content);
             Assert.Equal(string.Format(@"C:\TestSite\_site\{0}SomeFile.md", currentDate.Replace("/", "-")), siteContext.Pages[0].Filepath);
             Assert.Equal(filePath, siteContext.Pages[0].File);
-            Assert.Equal(2, siteContext.Pages[0].Bag.Count);
+            Assert.Equal(3, siteContext.Pages[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Pages[0].Bag["param"]);
         }
 
@@ -827,7 +827,7 @@ public void post_default_values()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Posts[0].Content);
             Assert.Equal(@"C:\TestSite\_site\SomeFile.md", siteContext.Posts[0].Filepath);
             Assert.Equal(@"C:\TestSite\_posts\SomeFile.md", siteContext.Posts[0].File);
-            Assert.Equal(2, siteContext.Posts[0].Bag.Count);
+            Assert.Equal(3, siteContext.Posts[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Posts[0].Bag["param"]);
         }
 
@@ -851,12 +851,38 @@ public void post_metadata_values()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Posts[0].Content);
             Assert.Equal(@"C:\TestSite\_site\SomeFile.md", siteContext.Posts[0].Filepath);
             Assert.Equal(@"C:\TestSite\_posts\SomeFile.md", siteContext.Posts[0].File);
-            Assert.Equal(3, siteContext.Posts[0].Bag.Count);
+            Assert.Equal(4, siteContext.Posts[0].Bag.Count); // title, date, param, excerpt
             Assert.Equal("value", siteContext.Posts[0].Bag["param"]);
             Assert.Equal("my title", siteContext.Posts[0].Bag["title"]);
             Assert.Equal(currentDate, siteContext.Posts[0].Bag["date"]);
         }
 
+        [Fact]
+        public void post_with_excerpt()
+        {
+            fileSystem.AddFile(@"C:\TestSite\_posts\SomeFile.md", new MockFileData(string.Format(@"One<!--more-->Two")));
+
+            // act
+            var siteContext = generator.BuildContext(@"C:\TestSite", false);
+
+            Assert.Equal(1, siteContext.Posts.Count);
+            Assert.Equal("<p>One", siteContext.Posts[0].Excerpt);
+        }
+
+        [Fact]
+        public void post_with_excerpt_and_custom_separator()
+        {
+            fileSystem.AddFile(@"C:\TestSite\_posts\SomeFile.md", new MockFileData(string.Format(@"---
+excerpt_separator: <!--excerpt_separator-->
+---One<!--more-->Two<!--excerpt_separator-->Three")));
+
+            // act
+            var siteContext = generator.BuildContext(@"C:\TestSite", false);
+
+            Assert.Equal(1, siteContext.Posts.Count);
+            Assert.Equal("<p>One<!--more-->Two", siteContext.Posts[0].Excerpt);
+        }
+
         [Fact]
         public void post_with_date_in_title()
         {
@@ -876,7 +902,7 @@ public void post_with_date_in_title()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Posts[0].Content);
             Assert.Equal(string.Format(@"C:\TestSite\_site\{0}\SomeFile.md", currentDate.Replace("/", "\\")), siteContext.Posts[0].Filepath);
             Assert.Equal(filePath, siteContext.Posts[0].File);
-            Assert.Equal(2, siteContext.Posts[0].Bag.Count);
+            Assert.Equal(3, siteContext.Posts[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Posts[0].Bag["param"]);
         }
 
@@ -899,7 +925,7 @@ public void post_with_false_date_in_title()
             Assert.Equal("<h1>Title</h1>\n", siteContext.Posts[0].Content);
             Assert.Equal(string.Format(@"C:\TestSite\_site\{0}SomeFile.md", currentDate.Replace("/", "\\")), siteContext.Posts[0].Filepath);
             Assert.Equal(filePath, siteContext.Posts[0].File);
-            Assert.Equal(2, siteContext.Posts[0].Bag.Count);
+            Assert.Equal(3, siteContext.Posts[0].Bag.Count); // param, excerpt, date
             Assert.Equal("value", siteContext.Posts[0].Bag["param"]);
         }
 

src/Pretzel.Tests/Templating/Jekyll/LiquidEngineTests.cs

@@ -967,6 +967,36 @@ public void The_Output_Should_Have_Been_Transformed()
             }
         }
 
+        public class Given_Page_Has_Excerpt : BakingEnvironment<LiquidEngine>
+        {
+            const string IndexContents = "---\r\n title: index\r\n show: true \r\n---\r\n\r\n{% for post in site.posts %}{{ post.excerpt }}{% endfor %}";
+            const string PostContents = "---\r\n layout: nil \r\n---\r\n\r\n<p>One<!--more-->Two</p>";
+            const string ExpectedIndexContents = "<p><p>One</p>";       
+
+            public override LiquidEngine Given()
+            {
+                var engine = new LiquidEngine();
+                engine.Initialize();
+                return engine;
+            }
+
+            public override void When()
+            {
+                FileSystem.AddFile(@"C:\website\index.md", new MockFileData(IndexContents));
+                FileSystem.AddFile(@"C:\website\_posts\2015-02-03-post.md", new MockFileData(PostContents));
+                var generator = new SiteContextGenerator(FileSystem, Enumerable.Empty<IContentTransform>());
+                var context = generator.BuildContext(@"C:\website\", false);
+                Subject.FileSystem = FileSystem;
+                Subject.Process(context);
+            }
+
+            [Fact]
+            public void Posts_Should_Have_Excerpt()
+            {
+                Assert.Equal(ExpectedIndexContents, FileSystem.File.ReadAllText(@"C:\website\_site\index.html").RemoveWhiteSpace());                    
+            }
+        }
+
         public class Given_Page_Has_HighlightBlock : BakingEnvironment<LiquidEngine>
         {
             const string PageContents = "---\r\n layout: nil \r\n---\r\n\r\n{% highlight %}a word{% endhighlight %}";