Update href implementation based on PR comments

source/dsl/DangerUtilsDSL.ts

@@ -7,17 +7,22 @@ export interface DangerUtilsDSL {
   /**
    * Creates an HTML link.
    *
-   * @param {string} href The HTML link's destination
-   * @param {string} text The HTML link's text
-   * @returns {string} The HTML <a> tag
+   * If `href` and `text` are falsy, null is returned.
+   * If `href` is falsy and `text` is truthy, `text` is returned.
+   * If `href` is truthy and `text` is falsy, an <a> tag is returned with `href` as its href and text value.
+   * Otherwise, if `href` and `text` are truthy, an <a> tag is returned with the `href` and `text` inserted as expected.
+   *
+   * @param {string} href The HTML link's destination.
+   * @param {string} text The HTML link's text.
+   * @returns {string|null} The HTML <a> tag.
    */
-  href(href: string, text: string): string
+  href(href: string, text: string): string | null
 
   /**
    * Converts an array of strings into a sentence.
    *
-   * @param {Array<string>} array The array of strings
-   * @returns {string} The sentence
+   * @param {Array<string>} array The array of strings.
+   * @returns {string} The sentence.
    */
   sentence(array: Array<string>): string
 }

source/runner/DangerUtils.ts

@@ -8,6 +8,12 @@ export function sentence(array: Array<string>): string {
   return array.slice(0, array.length - 1).join(", ") + " and " + array.pop()
 }
 
-export function href(href: string, text: string): string {
-  return `<a href="${href || "#"}">${text || ""}</a>`
+export function href(href: string, text: string): string | null {
+  if (!href && !text) {
+    return null
+  }
+  if (!href && text) {
+    return text
+  }
+  return `<a href="${href}">${text || href}</a>`
 }

source/runner/_tests/DangerUtils.test.ts

@@ -17,11 +17,17 @@ describe("sentence()", () => {
 })
 
 describe("href()", () => {
+  it("returns null when href and text are falsy", () => {
+    expect(href("", "")).toEqual(null)
+  })
+  it("returns just the text when the href is missing", () => {
+    expect(href("", "Some text")).toEqual("Some text")
+  })
+  it("returns <a> tag with href as text when text is missing", () => {
+    expect(href("/path/to/file", "")).toEqual(`<a href="/path/to/file">/path/to/file</a>`)
+  })
   it("returns <a> tag for supplied href and text", () => {
     expect(href("http://danger.systems", "Danger"))
       .toEqual(`<a href="http://danger.systems">Danger</a>`)
   })
-  it("handles falsy input", () => {
-    expect(href(null, undefined)).toEqual(`<a href="#"></a>`)
-  })
 })