Added test cases for markdown-writer and fixed bugs which arose

2 files changed, 437 insertions, 26 deletions

diff --git a/lib/markdown-writer.js b/lib/markdown-writer.js
index 1bfa942..b63d104 100644
--- a/lib/markdown-writer.js
+++ b/lib/markdown-writer.js
@@ -1,55 +1,94 @@
 
+var _ = require("underscore");
+
 function mdElement(start, end) {
     if (end === undefined)
         end = start;
 
-    this.open = function(attributes) {
+    this.open = function(attrs) {
         return start;
     };
 
     this.close = function() {
         return end;
     };
+
+    this.empty = function(attrs) {
+        return this.open(attrs) + this.close();
+    };
 }
 function mdLink(link, text) {
     var attrs = {};
 
     this.open = function(attributes) {
-        attrs = attributes;
+        attrs = attributes || {};
+
         return "[";
     };
 
     this.close = function() {
         return (attrs[text] || "") + "](" + (attrs[link] || "") + ")";
     };
+
+    this.empty = function(attrs) {
+        // don't display empty content (this is mainly to remove images with no src data)
+        var content = this.open(attrs) + this.close();
+
+        if(content === "[]()") {
+            return "";
+        }
+
+        return content;
+    };
+}
+function mdList() {
+    this.open = function(attrs) {
+        return attrs.indent > -1 ? "\n" : "";
+    };
+
+    this.close = function(attrs) {
+        return attrs.indent > -1 ? "" : "\n";
+    };
+
+    this.empty = function(attrs) {
+        return this.open(attrs) + this.close();
+    };
 }
 function mdListItem() {
-    this.open = function(attributes) {
+    this.open = function(attrs) {
         var output = "";
 
-        for(var i = 0; i < attributes["indent"]; ++i)
+        for(var i = 0; i < attrs.indent; ++i) {
             output += "\t";
+        }
 
-        return output + (attributes["type"] === "ul" ? "-" : attributes["count"] + ".") + " ";
+        return output + (attrs.type === "ul" ? "-" : attrs.count + ".") + " ";
     };
 
     this.close = function() {
         return "\n";
     };
+
+    this.empty = function(attrs) {
+        return this.open(attrs) + this.close();
+    };
 }
 
 // map HTML tags to Markdown syntax
 var htmlmd = {
-    "h1": new mdElement("# ", "\n\n"),
-    "h2": new mdElement("## ", "\n\n"),
-    "h3": new mdElement("### ", "\n\n"),
-    "h4": new mdElement("#### ", "\n\n"),
-    "h5": new mdElement("##### ", "\n\n"),
-    "h6": new mdElement("###### ", "\n\n"),
-    "p": new mdElement("", "\n\n"),
+    // paragraphs elements use three line feeds to close
+    // this prevents them being caught by collapsing list elements in `asString`
+    // while still allowing them to be collapsed when multiple empty lines are removed
+    "h1": new mdElement("# ", "\n\n\n"),
+    "h2": new mdElement("## ", "\n\n\n"),
+    "h3": new mdElement("### ", "\n\n\n"),
+    "h4": new mdElement("#### ", "\n\n\n"),
+    "h5": new mdElement("##### ", "\n\n\n"),
+    "h6": new mdElement("###### ", "\n\n\n"),
+    "p": new mdElement("", "\n\n\n"),
     "br": new mdElement("", "  \n"),
-    "ul": new mdElement("\n", ""),
-    "ol": new mdElement("\n", ""),
+    "ul": new mdList(),
+    "ol": new mdList(),
     "li": new mdListItem(),
     "strong": new mdElement("**"),
     "em": new mdElement("*"),
@@ -59,6 +98,7 @@ var htmlmd = {
 
 function mdWriter() {
     var fragments = [];
+    var listStack = [];
     var list = {
         indent: -1,
         type: "ul",
@@ -66,21 +106,27 @@ function mdWriter() {
     };
     
     function isList(tagName) {
-        return tagName == "ul" || tagName == "ol";
+        return tagName === "ul" || tagName === "ol";
     }
 
     function open(tagName, attributes) {
         if(htmlmd[tagName]) {
-            if(tagName == "li") {
-                attributes = attributes || {};
-                attributes["indent"] = list.indent;
-                attributes["type"] = list.type;
-                attributes["count"] = ++list.count;
+            attributes = attributes || {};
+
+            if(tagName === "li") {
+                attributes.indent = list.indent;
+                attributes.type = list.type;
+                attributes.count = ++list.count;
+            }
+            else if(isList(tagName)) {
+                attributes.indent = list.indent;
             }
 
             fragments.push(htmlmd[tagName].open(attributes));
 
             if(isList(tagName)) {
+                listStack.push(_.clone(list));
+
                 list.type = tagName;
                 list.indent++;
                 list.count = 0;
@@ -90,18 +136,17 @@ function mdWriter() {
     
     function close(tagName) {
         if(htmlmd[tagName]) {
-            fragments.push(htmlmd[tagName].close());
-
             if(isList(tagName)) {
-                list.indent--;
+                list = listStack.pop();
             }
+
+            fragments.push(htmlmd[tagName].close(list));
         }
     }
     
     function selfClosing(tagName, attributes) {
         if(htmlmd[tagName]) {
-            fragments.push(htmlmd[tagName].open(attributes));
-            fragments.push(htmlmd[tagName].close());
+            fragments.push(htmlmd[tagName].empty(attributes));
         }
     }
     
@@ -114,7 +159,8 @@ function mdWriter() {
     }
     
     function asString() {
-        return fragments.join("").replace(/\n{2,}/, "\n\n");
+        // massage the output to collapse mulitple empty lines and empty lines between nested lists
+        return fragments.join("").replace(/\n{2}(\t*)([2-9]\d*\.|- )/g, "\n$1$2").replace(/\n{3,}/g, "\n\n");
     }
 
     return {
diff --git a/tests/markdown-writer.tests.js b/tests/markdown-writer.tests.js
new file mode 100644
index 0000000..bf3df1b
--- /dev/null
+++ b/tests/markdown-writer.tests.js
@@ -0,0 +1,365 @@
+var assert = require("assert");
+var test = require("./testing").test;
+var mdWriter = require("../lib/markdown-writer");
+
+describe('markdown-writer', function() {
+    test('can generate a paragraph', function() {
+        var writer = mdWriter.writer();
+        writer.open("p");
+        writer.text("Hello");
+        writer.close("p");
+        return assert.equal(writer.asString(), "Hello\n\n");
+    });
+
+    test('can generate a level 1 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h1");
+        writer.text("Hello");
+        writer.close("h1");
+        return assert.equal(writer.asString(), "# Hello\n\n");
+    });
+
+    test('can generate a level 2 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h2");
+        writer.text("Hello");
+        writer.close("h2");
+        return assert.equal(writer.asString(), "## Hello\n\n");
+    });
+
+    test('can generate a level 3 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h3");
+        writer.text("Hello");
+        writer.close("h3");
+        return assert.equal(writer.asString(), "### Hello\n\n");
+    });
+
+    test('can generate a level 4 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h4");
+        writer.text("Hello");
+        writer.close("h4");
+        return assert.equal(writer.asString(), "#### Hello\n\n");
+    });
+
+    test('can generate a level 5 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h5");
+        writer.text("Hello");
+        writer.close("h5");
+        return assert.equal(writer.asString(), "##### Hello\n\n");
+    });
+
+    test('can generate a level 6 heading', function() {
+        var writer = mdWriter.writer();
+        writer.open("h6");
+        writer.text("Hello");
+        writer.close("h6");
+        return assert.equal(writer.asString(), "###### Hello\n\n");
+    });
+
+    test('can generate a new line', function() {
+        var writer = mdWriter.writer();
+        writer.text("Hello World");
+        writer.selfClosing("br");
+        return assert.equal(writer.asString(), "Hello World  \n");
+    });
+
+    test('can generate strong text', function() {
+        var writer = mdWriter.writer();
+        writer.text("Hello ");
+        writer.open("strong");
+        writer.text("World");
+        writer.close("strong");
+        return assert.equal(writer.asString(), "Hello **World**");
+    });
+    
+    test('can generate emphasis text', function() {
+        var writer = mdWriter.writer();
+        writer.text("Hello ");
+        writer.open("em");
+        writer.text("World");
+        writer.close("em");
+        return assert.equal(writer.asString(), "Hello *World*");
+    });
+
+    test('can generate hyperlinks', function() {
+        var writer = mdWriter.writer();
+        writer.open("a", { "href": "http://example.com" });
+        writer.text("Hello");
+        writer.close("a");
+        return assert.equal(writer.asString(), "[Hello](http://example.com)");
+    });
+
+    test('can generate hyperlinks with missing href attribute', function() {
+        var writer = mdWriter.writer();
+        writer.open("a", {});
+        writer.text("Hello");
+        writer.close("a");
+        return assert.equal(writer.asString(), "[Hello]()");
+    });
+
+    test('can generate hyperlinks with empty attributes', function() {
+        var writer = mdWriter.writer();
+        writer.open("a");
+        writer.text("Hello");
+        writer.close("a");
+        return assert.equal(writer.asString(), "[Hello]()");
+    });
+
+    test('can generate images', function() {
+        var writer = mdWriter.writer();
+        writer.selfClosing("img", { "src": "http://example.com/image.jpg", "alt": "Alt Text" });
+        return assert.equal(writer.asString(), "[Alt Text](http://example.com/image.jpg)");
+    });
+
+    test('can generate images with missing alt attribute', function() {
+        var writer = mdWriter.writer();
+        writer.selfClosing("img", { "src": "http://example.com/image.jpg" });
+        return assert.equal(writer.asString(), "[](http://example.com/image.jpg)");
+    });
+
+    test('can generate images with misssing src attribute', function() {
+        var writer = mdWriter.writer();
+        writer.selfClosing("img", { "alt": "Alt Text" });
+        return assert.equal(writer.asString(), "[Alt Text]()");
+    });
+
+    test("doesn't display empty images", function() {
+        var writer = mdWriter.writer();
+        writer.selfClosing("img");
+        return assert.equal(writer.asString(), "");
+    });
+
+    test('can generate an ordered list', function() {
+        var writer = mdWriter.writer();
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Hello");
+        writer.close("li");
+        writer.open("li");
+        writer.text("World");
+        writer.close("li");
+        writer.close("ol");
+        return assert.equal(writer.asString(), "1. Hello\n2. World\n\n");
+    });
+
+    test('can generate an unordered list', function() {
+        var writer = mdWriter.writer();
+        writer.open("ul");
+        writer.open("li");
+        writer.text("Hello");
+        writer.close("li");
+        writer.open("li");
+        writer.text("World");
+        writer.close("li");
+        writer.close("ul");
+        return assert.equal(writer.asString(), "- Hello\n- World\n\n");
+    });
+
+    test('can generate a nested ordered list with correct numbering', function() {
+        var writer = mdWriter.writer();
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Outer One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Two");
+
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Nested One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Two");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Three");
+        writer.close("li");
+        writer.close("ol");
+
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Three");
+        writer.close("li");
+        writer.close("ol");
+        return assert.equal(writer.asString(), "1. Outer One\n2. Outer Two\n\t1. Nested One\n\t2. Nested Two\n\t3. Nested Three\n3. Outer Three\n\n");
+    });
+
+    test('can generate a multi-level nested ordered list with correct numbering', function() {
+        var writer = mdWriter.writer();
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Outer One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Two");
+
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Nested One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Two");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Three");
+
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Inner One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Inner Two");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Inner Three");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Inner Four");
+        writer.close("li");
+        writer.close("ol");
+
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Four");
+        writer.close("li");
+        writer.close("ol");
+
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Three");
+        writer.close("li");
+        writer.close("ol");
+        return assert.equal(writer.asString(), "1. Outer One\n2. Outer Two\n\t1. Nested One\n\t2. Nested Two\n\t3. Nested Three\n\t\t1. Inner One\n\t\t2. Inner Two\n\t\t3. Inner Three\n\t\t4. Inner Four\n\t4. Nested Four\n3. Outer Three\n\n");
+    });
+
+    test('can generate sequential ordered lists with correct numbering', function() {
+        var writer = mdWriter.writer();
+        writer.open("ol");
+        writer.open("li");
+        writer.text("First One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("First Two");
+        writer.close("li");
+        writer.close("ol");
+
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Second One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Second Two");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Second Three");
+        writer.close("li");
+        writer.close("ol");
+
+        return assert.equal(writer.asString(), "1. First One\n2. First Two\n\n1. Second One\n2. Second Two\n3. Second Three\n\n");
+    });
+
+    test('can generate a nested unordered list', function() {
+        var writer = mdWriter.writer();
+        writer.open("ul");
+        writer.open("li");
+        writer.text("Outer One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Two");
+
+        writer.open("ul");
+        writer.open("li");
+        writer.text("Nested One");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Two");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Nested Three");
+        writer.close("li");
+        writer.close("ul");
+
+        writer.close("li");
+        writer.open("li");
+        writer.text("Outer Three");
+        writer.close("li");
+        writer.close("ul");
+        return assert.equal(writer.asString(), "- Outer One\n- Outer Two\n\t- Nested One\n\t- Nested Two\n\t- Nested Three\n- Outer Three\n\n");
+    });
+
+    test('can nest inline elements', function() {
+        var writer = mdWriter.writer();
+        writer.open("p");
+        writer.text("Lorem ");
+        writer.open("strong");
+        writer.text("ipsum ");
+        writer.open("em");
+        writer.text("dolor");
+        writer.close("em");
+        writer.text(" sit");
+        writer.close("strong");
+        writer.text(" amet");
+        writer.close("p");
+        return assert.equal(writer.asString(), "Lorem **ipsum *dolor* sit** amet\n\n");
+    });
+
+    test('can emphasise list text', function() {
+        var writer = mdWriter.writer();
+        writer.open("ol");
+        writer.open("li");
+        writer.text("Hello ");
+        writer.open("strong");
+        writer.text("Strong");
+        writer.close("strong");
+        writer.text(" World");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Hello ");
+        writer.open("em");
+        writer.text("Emphasis");
+        writer.close("em");
+        writer.text(" World");
+        writer.close("li");
+        writer.close("ol");
+        return assert.equal(writer.asString(), "1. Hello **Strong** World\n2. Hello *Emphasis* World\n\n");
+    });
+
+    test('blank paragraphs are removed', function() {
+        var writer = mdWriter.writer();
+        writer.open("p");
+        writer.text("Hello");
+        writer.close("p");
+        writer.open("p");
+        writer.text("");
+        writer.close("p");
+        writer.open("p");
+        writer.text("");
+        writer.close("p");
+        writer.open("p");
+        writer.text("World");
+        writer.close("p");
+        return assert.equal(writer.asString(), "Hello\n\nWorld\n\n");
+    });
+
+    test('generates correct spacing between paragraphs and lists', function() {
+        var writer = mdWriter.writer();
+        writer.open("p");
+        writer.text("Hello World");
+        writer.close("p");
+        writer.open("ul");
+        writer.open("li");
+        writer.text("First Item");
+        writer.close("li");
+        writer.open("li");
+        writer.text("Second Item");
+        writer.close("li");
+        writer.close("ul");
+        writer.open("p");
+        writer.text("Hello World");
+        writer.close("p");
+        return assert.equal(writer.asString(), "Hello World\n\n- First Item\n- Second Item\n\nHello World\n\n");
+    });
+});