diff --git a/src/diff-parser.ts b/src/diff-parser.ts
index 00f597d..7a5fc5d 100644
--- a/src/diff-parser.ts
+++ b/src/diff-parser.ts
@@ -23,7 +23,7 @@ function getFilename(line: string, linePrefix?: string, extraPrefix?: string): s
     ? new RegExp(`^${escapeForRegExp(linePrefix)} "?(.+?)"?$`)
     : new RegExp('^"?(.+?)"?$');
 
-  const [, filename = ""] = FilenameRegExp.exec(line) || []; // TODO: Check if this is safe
+  const [, filename = ""] = FilenameRegExp.exec(line) || [];
   const matchingPrefix = prefixes.find(p => filename.indexOf(p) === 0);
   const fnameWithoutPrefix = matchingPrefix ? filename.slice(matchingPrefix.length) : filename;
 
@@ -132,7 +132,6 @@ export function parse(diffInput: string, config: DiffParserConfig = {}): DiffFil
     saveBlock();
     saveFile();
 
-    // TODO: Avoid disabling types
     // eslint-disable-next-line
     // @ts-ignore
     currentFile = {
@@ -183,7 +182,6 @@ export function parse(diffInput: string, config: DiffParserConfig = {}): DiffFil
     }
 
     /* Create block metadata */
-    // TODO: Avoid disabling types
     // eslint-disable-next-line
     // @ts-ignore
     currentBlock = {
@@ -198,7 +196,6 @@ export function parse(diffInput: string, config: DiffParserConfig = {}): DiffFil
   function createLine(line: string): void {
     if (currentFile === null || currentBlock === null || oldLine === null || newLine === null) return;
 
-    // TODO: Avoid disabling types
     // eslint-disable-next-line
     // @ts-ignore
     const currentLine: DiffLine = {
@@ -208,7 +205,6 @@ export function parse(diffInput: string, config: DiffParserConfig = {}): DiffFil
     const addedPrefixes = currentFile.isCombined ? ["+ ", " +", "++"] : ["+"];
     const deletedPrefixes = currentFile.isCombined ? ["- ", " -", "--"] : ["-"];
 
-    // TODO: Check if this makes sense for combined diff
     if (startsWithAny(line, addedPrefixes)) {
       currentFile.addedLines++;
       currentLine.type = LineType.INSERT;
diff --git a/src/diff2html.ts b/src/diff2html.ts
index 2b22b9c..1275eeb 100644
--- a/src/diff2html.ts
+++ b/src/diff2html.ts
@@ -39,10 +39,5 @@ export function html(diffInput: string | DiffFile[], configuration: Diff2HtmlCon
       ? new SideBySideRenderer(hoganUtils, config).render(diffJson)
       : new LineByLineRenderer(hoganUtils, config).render(diffJson);
 
-  // TODO: Review error handling
-  if (diffOutput === undefined) {
-    throw new Error("OMG we haz no diff. Why???");
-  }
-
   return fileList + diffOutput;
 }
diff --git a/src/line-by-line-renderer.ts b/src/line-by-line-renderer.ts
index 8e609de..02fd731 100644
--- a/src/line-by-line-renderer.ts
+++ b/src/line-by-line-renderer.ts
@@ -39,7 +39,7 @@ export default class LineByLineRenderer {
     this.config = { ...defaultLineByLineRendererConfig, ...config };
   }
 
-  render(diffFiles: DiffFile[]): string | undefined {
+  render(diffFiles: DiffFile[]): string {
     const diffsHtml = diffFiles
       .map(file => {
         let diffs;
@@ -55,7 +55,6 @@ export default class LineByLineRenderer {
     return this.hoganUtils.render(genericTemplatesPath, "wrapper", { content: diffsHtml });
   }
 
-  // TODO: Make this private after improving tests
   makeFileDiffHtml(file: DiffFile, diffs: string): string {
     if (this.config.renderNothingWhenEmpty && Array.isArray(file.blocks) && file.blocks.length === 0) return "";
 
@@ -80,7 +79,6 @@ export default class LineByLineRenderer {
     });
   }
 
-  // TODO: Make this private after improving tests
   generateEmptyDiff(): string {
     return this.hoganUtils.render(genericTemplatesPath, "empty-diff", {
       contentClass: "d2h-code-line",
@@ -192,7 +190,6 @@ export default class LineByLineRenderer {
     return matches;
   }
 
-  // TODO: Make this private after improving tests
   processChangedLines(isCombined: boolean, oldLines: DiffLine[], newLines: DiffLine[]): FileHtml {
     const fileHtml = {
       right: "",
@@ -253,7 +250,6 @@ export default class LineByLineRenderer {
     return fileHtml;
   }
 
-  // TODO: Make this private after improving tests
   generateLineHtml(oldLine?: DiffPreparedLine, newLine?: DiffPreparedLine): FileHtml {
     return {
       left: this.generateSingleLineHtml(oldLine),
diff --git a/src/render-utils.ts b/src/render-utils.ts
index b32317b..73a1c60 100644
--- a/src/render-utils.ts
+++ b/src/render-utils.ts
@@ -113,7 +113,6 @@ export function deconstructLine(line: string, isCombined: boolean): DiffLinePart
  *        returns "my/path/{to → for}/file.js"
  */
 export function filenameDiff(file: DiffFileName): string {
-  // TODO: Review this huuuuuge piece of code, do we need this?
   // TODO: Move unify path to parsing
   const oldFilename = unifyPath(file.oldName);
   const newFilename = unifyPath(file.newName);
diff --git a/src/side-by-side-renderer.ts b/src/side-by-side-renderer.ts
index d7f714b..72daa14 100644
--- a/src/side-by-side-renderer.ts
+++ b/src/side-by-side-renderer.ts
@@ -39,7 +39,7 @@ export default class SideBySideRenderer {
     this.config = { ...defaultSideBySideRendererConfig, ...config };
   }
 
-  render(diffFiles: DiffFile[]): string | undefined {
+  render(diffFiles: DiffFile[]): string {
     const diffsHtml = diffFiles
       .map(file => {
         let diffs;
@@ -55,7 +55,6 @@ export default class SideBySideRenderer {
     return this.hoganUtils.render(genericTemplatesPath, "wrapper", { content: diffsHtml });
   }
 
-  // TODO: Make this private after improving tests
   makeFileDiffHtml(file: DiffFile, diffs: FileHtml): string {
     if (this.config.renderNothingWhenEmpty && Array.isArray(file.blocks) && file.blocks.length === 0) return "";
 
@@ -80,7 +79,6 @@ export default class SideBySideRenderer {
     });
   }
 
-  // TODO: Make this private after improving tests
   generateEmptyDiff(): FileHtml {
     return {
       right: "",
@@ -207,7 +205,6 @@ export default class SideBySideRenderer {
     return matches;
   }
 
-  // TODO: Make this private after improving tests
   makeHeaderHtml(blockHeader: string): string {
     return this.hoganUtils.render(genericTemplatesPath, "block-header", {
       CSSLineClass: renderUtils.CSSLineClass,
@@ -217,7 +214,6 @@ export default class SideBySideRenderer {
     });
   }
 
-  // TODO: Make this private after improving tests
   processChangedLines(isCombined: boolean, oldLines: DiffLine[], newLines: DiffLine[]): FileHtml {
     const fileHtml = {
       right: "",
@@ -276,7 +272,6 @@ export default class SideBySideRenderer {
     return fileHtml;
   }
 
-  // TODO: Make this private after improving tests
   generateLineHtml(oldLine?: DiffPreparedLine, newLine?: DiffPreparedLine): FileHtml {
     return {
       left: this.generateSingleHtml(oldLine),