Fix double blank lines in content

src/lib/content-creator.js

@@ -142,7 +142,10 @@ class ContentCreator {
       return this.contentCache.get( status.id );
     }
 
-    const content = this.convertContent( status.content );
+    const content = this.fixDoubleLineSpaces(
+      this.convertContent( status.content )
+    );
+
     this.contentCache.set( status.id, content );
     return content;
   }
@@ -344,6 +347,30 @@ class ContentCreator {
 
   }
 
+  /**
+   * Use the first sentences to make a post description.
+   * See this {@linkhttps://stackoverflow.com/a/49432524|Stack Overflow} post for
+   * original implementation.
+   * @param {string} markdownContent The content in Markdown format.
+   * @throws {TypeError} If the parameter is incorrect.
+   * @returns {string} The description of the content using the first sentences.
+   */
+  fixDoubleLineSpaces( markdownContent ) {
+
+    if ( markdownContent === undefined ) {
+      throw new TypeError( "The markdownContent parameter is required" );
+    }
+
+    if ( typeof markdownContent !== "string" ) {
+      throw new TypeError( "The markdownContent parameter must be a string" );
+    }
+
+    // eslint-disable-next-line no-control-regex
+    var regExp = new RegExp( "(\n){3,}", "gm" );
+    return markdownContent.replace( regExp, "\n\n" );
+
+  }
+
   /**
    * Make it easy to throw a consistent error message.
    * @param {string} propertyName The name of the property that wasn't found.

tests/lib/content-creator.test.js

@@ -59,6 +59,15 @@ const expectedTitle = "Hello Blowerians! There's been an uptick in reported post
 const expectedDescr = "Hello Blowerians! There's been an uptick in reported posts lately, for probably obvious reasons…";
 /* eslint-enable max-len, no-useless-escape */
 
+const testDoubleLineSpace = `Lorem ipsum odor amet, consectetuer adipiscing elit.
+
+
+Ornare dis malesuada vestibulum maximus aliquet etiam.`;
+
+const expectedDoubleLineSpace = `Lorem ipsum odor amet, consectetuer adipiscing elit.
+
+Ornare dis malesuada vestibulum maximus aliquet etiam.`;
+
 describe( "ContentCreator", () => {
 
   describe( "constructor", () => {
@@ -517,4 +526,48 @@ describe( "ContentCreator", () => {
     } );
 
   } );
+
+  describe( "fixDoubleLineSpaces", () => {
+
+    it( "should throw an error when the parameter is incorrect", () => {
+      const contentCreator = new ContentCreator();
+
+      assert.throws(
+        () => {
+          contentCreator.fixDoubleLineSpaces();
+        },
+        {
+          name: "TypeError",
+          message: /is required/
+        }
+      );
+
+      assert.throws(
+        () => {
+          contentCreator.fixDoubleLineSpaces( 1234 );
+        },
+        {
+          name: "TypeError",
+          message: /must be a string/
+        }
+      );
+
+      assert.doesNotThrow(
+        () => {
+          contentCreator.fixDoubleLineSpaces( testLongContent );
+        }
+      );
+
+    } );
+
+    it( "should make the expected description", () => {
+      const contentCreator = new ContentCreator();
+      const testContent = contentCreator.fixDoubleLineSpaces( testDoubleLineSpace );
+      assert.equal(
+        testContent,
+        expectedDoubleLineSpace
+      );
+    } );
+
+  } );
 } );