JavaScript: Fix parser prefix assignment bug

rewrite-javascript/rewrite/src/javascript/parser.ts

@@ -2637,11 +2637,10 @@ export class JavaScriptParserVisitor {
     }
 
     visitVariableStatement(node: ts.VariableStatement): JS.ScopedVariableDeclarations | J.VariableDeclarations {
+        const prefix = this.prefix(node);
         return produce(this.visitVariableDeclarationList(node.declarationList), draft => {
-            if (node.modifiers) {
-                draft.modifiers = this.mapModifiers(node).concat(draft.modifiers);
-            }
-            draft.prefix = this.prefix(node);
+            draft.prefix = prefix;
+            draft.modifiers = this.mapModifiers(node).concat(draft.modifiers);
         });
     }
 
@@ -3064,7 +3063,7 @@ export class JavaScriptParserVisitor {
             modifiers.push({
                 kind: J.Kind.Modifier,
                 id: randomId(),
-                prefix: this.prefix(kind),
+                prefix: modifiers.length === 0 ? this.prefix(kind) : this.prefix(kind),
                 markers: emptyMarkers,
                 annotations: [],
                 keyword: kind.kind === ts.SyntaxKind.VarKeyword ? 'var' :

rewrite-javascript/rewrite/test/javascript/format/format.test.ts

@@ -100,7 +100,6 @@ describe('AutoformatVisitor', () => {
                     if (1 > 0) {
                         console.log("four", "three", "six");
                     }
-
                     let i = 1;
                     while (i < 4) {
                         i++;
@@ -112,7 +111,6 @@ describe('AutoformatVisitor', () => {
                     } finally {
                         console.log("finally");
                     }
-
                     const isTypeScriptFun = i > 3 ? "yes" : "hell yeah!";
                     for (let j = 1; j <= 5; j++) {
                         console.log(\`Number: \` + j);
@@ -138,7 +136,6 @@ describe('AutoformatVisitor', () => {
         )});
 
     test('a statement following an if', () => {
-        // TODO not sure if there should be a newline after the if
         return spec.rewriteRun(
             // @formatter:off
             //language=typescript
@@ -150,7 +147,6 @@ describe('AutoformatVisitor', () => {
             `
             if (1 > 0) {
             }
-
             let i = 1;
             `)
             // @formatter:on

rewrite-javascript/rewrite/test/javascript/remove-import.test.ts

@@ -959,5 +959,48 @@ describe('RemoveImport visitor', () => {
                 )
             );
         });
+
+        test('should remove leading empty lines with variable declaration', async () => {
+            const spec = new RecipeSpec();
+            spec.recipe = fromVisitor(new RemoveImport("fs", "readFile"));
+
+            //language=typescript
+            await spec.rewriteRun(
+                typescript(
+                    `
+                        import {readFile} from "fs";
+
+                        const foo = 1;
+                        console.log(foo);
+                    `,
+                    `
+                        const foo = 1;
+                        console.log(foo);`
+                )
+            );
+        });
+
+        test('should remove leading empty lines with function declaration', async () => {
+            const spec = new RecipeSpec();
+            spec.recipe = fromVisitor(new RemoveImport("fs", "readFile"));
+
+            //language=typescript
+            await spec.rewriteRun(
+                typescript(
+                    `
+                        import {readFile} from "fs";
+
+                        function foo() {
+                            return 42;
+                        }
+                    `,
+                    `
+                        function foo() {
+                            return 42;
+                        }
+                    `
+                )
+            );
+        });
     });
 });