removing array manipulations

src/common/printer-helpers.js

@@ -37,35 +37,27 @@ export const printComments = (node, path, options, filter = () => true) => {
 };
 
 export function printPreservingEmptyLines(path, key, options, print) {
-  const parts = [];
-  path.each((childPath, index) => {
+  return path.map((childPath, index) => {
     const node = childPath.getValue();
-    const nodeType = node.type;
 
-    if (
-      // Avoid adding a hardline at the beginning of the document.
-      parts.length !== 0 &&
+    return [
+      // Only attempt to prepend an empty line if `node` is not the first item
+      index > 0 &&
       // LabelDefinition adds a dedented line so we don't have to prepend a
       // hardline.
-      nodeType !== 'LabelDefinition'
-    ) {
-      parts.push(hardline);
-    }
-
-    parts.push(print(childPath));
-
-    // Only attempt to append an empty line if `node` is not the last item
-    if (
+      node.type !== 'LabelDefinition'
+        ? hardline
+        : '',
+      print(childPath),
+      // Only attempt to append an empty line if `node` is not the last item
       !isLast(childPath, key, index) &&
+      // Append an empty line if the original text already had an one after the
+      // current `node`
       isNextLineEmpty(options.originalText, options.locEnd(node) + 1)
-    ) {
-      // Append an empty line if the original text already had an one after
-      // the current `node`
-      parts.push(hardline);
-    }
+        ? hardline
+        : ''
+    ];
   }, key);
-
-  return parts;
 }
 
 // This function will add an indentation to the `item` and separate it from the
@@ -77,10 +69,10 @@ export const printSeparatedItem = (
     lastSeparator = firstSeparator,
     grouped = true
   } = {}
-) => {
-  const document = [indent([firstSeparator, item]), lastSeparator];
-  return grouped ? group(document) : document;
-};
+) =>
+  grouped
+    ? group([indent([firstSeparator, item]), lastSeparator])
+    : [indent([firstSeparator, item]), lastSeparator];
 
 // This function will add an indentation to the `list` and separate it from the
 // rest of the `doc` in most cases by a `softline`.

src/nodes/AssemblyLocalDefinition.js

@@ -4,17 +4,9 @@ import { printSeparatedList } from '../common/printer-helpers.js';
 const { line } = doc.builders;
 
 export const AssemblyLocalDefinition = {
-  print: ({ node, path, print }) => {
-    const parts = [
-      'let',
-      printSeparatedList(path.map(print, 'names'), { firstSeparator: line })
-    ];
-
-    if (node.expression !== null) {
-      parts.push(':= ');
-      parts.push(path.call(print, 'expression'));
-    }
-
-    return parts;
-  }
+  print: ({ node, path, print }) => [
+    'let',
+    printSeparatedList(path.map(print, 'names'), { firstSeparator: line }),
+    node.expression ? [':= ', path.call(print, 'expression')] : ''
+  ]
 };

src/nodes/ExpressionStatement.js

@@ -5,23 +5,15 @@ const { hardline } = doc.builders;
 
 export const ExpressionStatement = {
   print: ({ node, options, path, print }) => {
-    const parts = [];
+    const comments =
+      path.getParentNode().type === 'IfStatement'
+        ? printComments(node, path, options)
+        : [];
 
-    const parent = path.getParentNode();
-
-    if (parent.type === 'IfStatement') {
-      if (node.comments?.length) {
-        const comments = printComments(node, path, options);
-        if (comments?.length) {
-          parts.push(comments);
-          parts.push(hardline);
-        }
-      }
-    }
-
-    parts.push(path.call(print, 'expression'));
-    parts.push(node.omitSemicolon ? [] : ';');
-
-    return parts;
+    return [
+      comments.length ? [comments, hardline] : '',
+      path.call(print, 'expression'),
+      node.omitSemicolon ? '' : ';'
+    ];
   }
 };