Formatter: Keep herb:disable on same line as tag-opening (marcoroth#946)

Resolves marcoroth#913

Author: marcoroth

javascript/packages/formatter/src/format-printer.ts

@@ -709,13 +709,37 @@ export class FormatPrinter extends Printer {
    * Render multiline attributes for a tag
    */
   private renderMultilineAttributes(tagName: string, allChildren: Node[] = [], isSelfClosing: boolean = false,) {
-    this.pushWithIndent(`<${tagName}`)
+    const herbDisableComments = allChildren.filter(child =>
+      isNode(child, ERBContentNode) && isHerbDisableComment(child)
+    )
+
+    let openingLine = `<${tagName}`
+
+    if (herbDisableComments.length > 0) {
+      const commentLines = this.capture(() => {
+        herbDisableComments.forEach(comment => {
+          const wasInlineMode = this.inlineMode
+          this.inlineMode = true
+          this.lines.push(" ")
+          this.visit(comment)
+          this.inlineMode = wasInlineMode
+        })
+      })
+
+      openingLine += commentLines.join("")
+    }
+
+    this.pushWithIndent(openingLine)
 
     this.withIndent(() => {
       allChildren.forEach(child => {
         if (isNode(child, HTMLAttributeNode)) {
           this.pushWithIndent(this.renderAttribute(child))
         } else if (!isNode(child, WhitespaceNode)) {
+          if (isNode(child, ERBContentNode) && isHerbDisableComment(child)) {
+            return
+          }
+
           this.visit(child)
         }
       })

javascript/packages/formatter/test/herb-disable-comment-formatting.test.ts

@@ -324,4 +324,20 @@ describe("herb:disable comment formatting", () => {
 
     expect(result).toBe(source)
   })
+
+  test("keeps herb:disable comment on same line as tag name in multiline opening tag", () => {
+    const source = dedent`
+      <a <%# herb:disable html-anchor-require-href %>
+        class="btn btn-secondary no-donate-btn"
+        aria-label="Close"
+        data-dismiss="modal"
+      >
+        Close
+      </a>
+    `
+
+    const result = formatter.format(source)
+
+    expect(result).toBe(source)
+  })
 })