Merge pull request #524 from gmsgowtham/fix/nested-heading

fix(minor): avoid wrapping heading inside two text nodes

Author: gmsgowtham

examples/react-native-marked-sample/src/const.ts

@@ -1,6 +1,7 @@
 const MD_STRING = `
 # h1 Heading
 ## h2 Heading
+## ~~_h2 Heading with Emphasis_~~
 ### h3 Heading
 #### h4 Heading
 ##### h5 Heading

src/lib/Parser.tsx

@@ -56,6 +56,13 @@ class Parser {
 			}
 			case "heading": {
 				const styles = this.headingStylesMap[token.depth];
+
+				// To avoid duplicate text node nesting when there are no child tokens with text emphasis (i.e., italic)
+				// ref: https://github.com/gmsgowtham/react-native-marked/issues/522
+				if (token.tokens.length === 1 && token.tokens[0]?.type === "text") {
+					return this.renderer.heading(token.text, styles, token.depth);
+				}
+
 				const children = this._parse(token.tokens, styles);
 				return this.renderer.heading(children, styles, token.depth);
 			}

src/lib/__tests__/Markdown.spec.tsx

@@ -72,6 +72,12 @@ describe("Headings", () => {
 		const tree = r.toJSON();
 		expect(tree).toMatchSnapshot();
 	});
+	it("Heading with text emphasis", () => {
+		const r = render(<Markdown value={"## ~~_Heading level 2_~~"} />);
+		expect(screen.queryByText("Heading level 2")).toBeTruthy();
+		const tree = r.toJSON();
+		expect(tree).toMatchSnapshot();
+	});
 });
 
 // https://www.markdownguide.org/basic-syntax/#paragraphs-1